id
stringlengths
9
13
submitter
stringlengths
1
64
authors
stringlengths
5
22.9k
title
stringlengths
4
245
comments
stringlengths
1
548
journal-ref
stringlengths
4
362
doi
stringlengths
12
82
report-no
stringlengths
2
281
categories
stringclasses
793 values
license
stringclasses
9 values
orig_abstract
stringlengths
24
1.95k
versions
listlengths
1
30
update_date
stringlengths
10
10
authors_parsed
listlengths
1
1.74k
abstract
stringlengths
21
1.95k
2310.18594
Umananda Dev Goswami
Ronit Karmakar and Umananda Dev Goswami
Quasinormal modes, temperatures and greybody factors of black holes in a generalized Rastall gravity theory
19 pages, 15 figures; Published version
Phys. Scr. 99 (2024) 055003
10.1088/1402-4896/ad350e
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
We introduce a modification in the energy-momentum conservation violating Rastall's theory of gravity and obtain a Reissner-Nordstr\"om-type black hole solution in spacetime surrounded by a cloud of strings and charge fields. We examine the horizons of the black hole along with the influence of the parameters of the model on it. The scalar quasinormal modes (QNMs) of oscillations of the black hole are also computed using the 6th order WKB approximation method. It is seen that the Rastall parameter $\beta$ and the newly introduced energy-momentum tensor trace parameter $\alpha$ as well as the charge parameter $q$ and strings field parameter $a$ influence the amplitude and damping of the QNMs. From the metric function, we obtain the temperature of the black hole and study the effects of the four model parameters $\beta$, $\alpha$, $q$ and $a$ on the temperature. We then examine the greybody factors associated with the black hole and the corresponding total absorption cross-section for it. It is seen that the modification we introduced in the Rastall theory has a drastic effect on various properties of the black hole and may lead to interesting outcomes in future when the better detection techniques will be available with the LISA and the Einstein Telescope.
[ { "created": "Sat, 28 Oct 2023 05:10:39 GMT", "version": "v1" }, { "created": "Sun, 17 Dec 2023 03:32:56 GMT", "version": "v2" }, { "created": "Wed, 10 Apr 2024 10:40:29 GMT", "version": "v3" } ]
2024-04-11
[ [ "Karmakar", "Ronit", "" ], [ "Goswami", "Umananda Dev", "" ] ]
We introduce a modification in the energy-momentum conservation violating Rastall's theory of gravity and obtain a Reissner-Nordstr\"om-type black hole solution in spacetime surrounded by a cloud of strings and charge fields. We examine the horizons of the black hole along with the influence of the parameters of the model on it. The scalar quasinormal modes (QNMs) of oscillations of the black hole are also computed using the 6th order WKB approximation method. It is seen that the Rastall parameter $\beta$ and the newly introduced energy-momentum tensor trace parameter $\alpha$ as well as the charge parameter $q$ and strings field parameter $a$ influence the amplitude and damping of the QNMs. From the metric function, we obtain the temperature of the black hole and study the effects of the four model parameters $\beta$, $\alpha$, $q$ and $a$ on the temperature. We then examine the greybody factors associated with the black hole and the corresponding total absorption cross-section for it. It is seen that the modification we introduced in the Rastall theory has a drastic effect on various properties of the black hole and may lead to interesting outcomes in future when the better detection techniques will be available with the LISA and the Einstein Telescope.
gr-qc/9802015
Ruth A. W. Gregory
Owen Dando and Ruth Gregory
Dilatonic global strings
18 pages RevTeX, 3 figures, references amended
Phys. Rev. D 58, 023502 (1998)
10.1103/PhysRevD.58.023502
DTP/98/1
gr-qc astro-ph hep-th
null
We examine the field equations of a self-gravitating global string in low energy superstring gravity, allowing for an arbitrary coupling of the global string to the dilaton. Massive and massless dilatons are considered. For the massive dilaton the spacetime is similar to the recently discovered non-singular time-dependent Einstein self-gravitating global string, but the massless dilaton generically gives a singular spacetime, even allowing for time-dependence. We also demonstrate a time-dependent non-singular string/anti-string configuration, in which the string pair causes a compactification of two of the spatial dimensions, albeit on a very large scale.
[ { "created": "Fri, 6 Feb 1998 15:21:54 GMT", "version": "v1" }, { "created": "Thu, 12 Feb 1998 17:23:37 GMT", "version": "v2" } ]
2016-08-25
[ [ "Dando", "Owen", "" ], [ "Gregory", "Ruth", "" ] ]
We examine the field equations of a self-gravitating global string in low energy superstring gravity, allowing for an arbitrary coupling of the global string to the dilaton. Massive and massless dilatons are considered. For the massive dilaton the spacetime is similar to the recently discovered non-singular time-dependent Einstein self-gravitating global string, but the massless dilaton generically gives a singular spacetime, even allowing for time-dependence. We also demonstrate a time-dependent non-singular string/anti-string configuration, in which the string pair causes a compactification of two of the spatial dimensions, albeit on a very large scale.
2010.15355
Titus K Mathew
Jerin Mohan N D and Titus K Mathew
On the feasibility of truncated Israel-Stewart model in the context of late acceleration
34 pages and 9 figures
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A dissipative model of the Universe based on the causal relativistic truncated Israel-Stewart theory is analysed in the context of recent accelerated expansion of the Universe. The bulk viscosity and relaxation time are taken as $\xi=\alpha\rho^s$ and $\tau=\frac{\alpha}{\epsilon\gamma(2-\gamma)}\rho^{s-1}$ respectively. For $s=1/2,$ we found an analytical solution for the Hubble parameter of the model. We have estimated the model parameters by treating $\gamma=1$ and $\gamma$ as a free parameter using the latest cosmological data. The model predicts a prior decelerated phase and an end de Sitter phase as in the standard $\Lambda$CDM model. The dynamical system analysis shows that the prior decelerated epoch is an unstable equilibrium, while the far future de Sitter epoch is stable. The age of the Universe obtained around $13.66$ Gyr, which is close to the recent observations. The second law of thermodynamics is found to be satisfied throughout the evolution in this model. The feasibility of the model has been checked by contrasting with models based on the full Israel-Stewart and the Eckart viscous theories. The truncated viscous model appears more compatible with astronomical observations than the Eckart and full causal viscous models.
[ { "created": "Thu, 29 Oct 2020 05:07:28 GMT", "version": "v1" }, { "created": "Thu, 12 Aug 2021 12:42:19 GMT", "version": "v2" } ]
2021-08-13
[ [ "D", "Jerin Mohan N", "" ], [ "Mathew", "Titus K", "" ] ]
A dissipative model of the Universe based on the causal relativistic truncated Israel-Stewart theory is analysed in the context of recent accelerated expansion of the Universe. The bulk viscosity and relaxation time are taken as $\xi=\alpha\rho^s$ and $\tau=\frac{\alpha}{\epsilon\gamma(2-\gamma)}\rho^{s-1}$ respectively. For $s=1/2,$ we found an analytical solution for the Hubble parameter of the model. We have estimated the model parameters by treating $\gamma=1$ and $\gamma$ as a free parameter using the latest cosmological data. The model predicts a prior decelerated phase and an end de Sitter phase as in the standard $\Lambda$CDM model. The dynamical system analysis shows that the prior decelerated epoch is an unstable equilibrium, while the far future de Sitter epoch is stable. The age of the Universe obtained around $13.66$ Gyr, which is close to the recent observations. The second law of thermodynamics is found to be satisfied throughout the evolution in this model. The feasibility of the model has been checked by contrasting with models based on the full Israel-Stewart and the Eckart viscous theories. The truncated viscous model appears more compatible with astronomical observations than the Eckart and full causal viscous models.
2110.15820
Odysse Halim
O. Halim, G. Vedovato, E. Milotti, G. A. Prodi, S. Bini, M. Drago, V. Gayathri, C. Lazzaro, D. Lopez, A. Miani, B. O'Brien, F. Salemi, M. Szczepanczyk, S. Tiwari, A. Virtuoso, S. Klimenko
The search of higher multipole radiation in gravitational waves from compact binary coalescences by a minimally-modelled pipeline
5 pages, Proceedings for the "17th International Conference on Topics in Astroparticle and Underground Physics (TAUP)"
null
10.1088/1742-6596/2156/1/012081
null
gr-qc astro-ph.IM
http://creativecommons.org/licenses/by/4.0/
The coherent WaveBurst (cWB) pipeline implements a minimally-modelled search to find a coherent response in the network of gravitational wave detectors of the LIGO-Virgo Collaboration in the time-frequency domain. In this manuscript, we provide a timely introduction to an extension of the cWB analysis to detect spectral features beyond the main quadrupolar emission of gravitational waves during the inspiral phase of compact binary coalescences; more detailed discussion will be provided in a forthcoming paper [1]. The search is performed by defining specific regions in the time-frequency map to extract the energy of harmonics of main quadrupole mode in the inspiral phase. This method has already been used in the GW190814 discovery paper (Astrophys. J. Lett. 896 L44). Here we show the procedure to detect the (3, 3) multipole in GW190814 within the cWB framework. Keywords: gravitational waves, analysis, multipoles, compact binary coalescences
[ { "created": "Fri, 29 Oct 2021 14:32:21 GMT", "version": "v1" } ]
2022-03-02
[ [ "Halim", "O.", "" ], [ "Vedovato", "G.", "" ], [ "Milotti", "E.", "" ], [ "Prodi", "G. A.", "" ], [ "Bini", "S.", "" ], [ "Drago", "M.", "" ], [ "Gayathri", "V.", "" ], [ "Lazzaro", "C.", "" ], [ "Lopez", "D.", "" ], [ "Miani", "A.", "" ], [ "O'Brien", "B.", "" ], [ "Salemi", "F.", "" ], [ "Szczepanczyk", "M.", "" ], [ "Tiwari", "S.", "" ], [ "Virtuoso", "A.", "" ], [ "Klimenko", "S.", "" ] ]
The coherent WaveBurst (cWB) pipeline implements a minimally-modelled search to find a coherent response in the network of gravitational wave detectors of the LIGO-Virgo Collaboration in the time-frequency domain. In this manuscript, we provide a timely introduction to an extension of the cWB analysis to detect spectral features beyond the main quadrupolar emission of gravitational waves during the inspiral phase of compact binary coalescences; more detailed discussion will be provided in a forthcoming paper [1]. The search is performed by defining specific regions in the time-frequency map to extract the energy of harmonics of main quadrupole mode in the inspiral phase. This method has already been used in the GW190814 discovery paper (Astrophys. J. Lett. 896 L44). Here we show the procedure to detect the (3, 3) multipole in GW190814 within the cWB framework. Keywords: gravitational waves, analysis, multipoles, compact binary coalescences
gr-qc/9712091
Fernando Lombardo
Fernando C. Lombardo and Francisco D. Mazzitelli
Influence functional in two dimensional dilaton gravity
25 pages, RevTex, no figures. Minor changes has been added. To appear in Physical Review D
Phys.Rev. D58 (1998) 024009
10.1103/PhysRevD.58.024009
null
gr-qc hep-th
null
We evaluate the influence functional for two dimensional models of dilaton gravity. This functional is exactly computed when the conformal invariance is preserved, and it can be written as the difference between the Liouville actions on each closed-time-path branch plus a boundary term. From the influence action we derive the covariant form of the semiclassical field equations. We also study the quantum to classical transition in cosmological backgrounds. In the conformal case we show that the semiclassical approximation is not valid because there is no imaginary part in the influence action. Finally we show that the inclusion of the dilaton loop in the influence functional breaks conformal invariance and ensures the validity of the semiclassical approximation.
[ { "created": "Tue, 23 Dec 1997 20:02:37 GMT", "version": "v1" }, { "created": "Tue, 14 Apr 1998 19:22:51 GMT", "version": "v2" } ]
2009-10-30
[ [ "Lombardo", "Fernando C.", "" ], [ "Mazzitelli", "Francisco D.", "" ] ]
We evaluate the influence functional for two dimensional models of dilaton gravity. This functional is exactly computed when the conformal invariance is preserved, and it can be written as the difference between the Liouville actions on each closed-time-path branch plus a boundary term. From the influence action we derive the covariant form of the semiclassical field equations. We also study the quantum to classical transition in cosmological backgrounds. In the conformal case we show that the semiclassical approximation is not valid because there is no imaginary part in the influence action. Finally we show that the inclusion of the dilaton loop in the influence functional breaks conformal invariance and ensures the validity of the semiclassical approximation.
0907.0462
Christian Reisswig
Christian Reisswig, Sascha Husa, Luciano Rezzolla, Ernst Nils Dorband, Denis Pollney, Jennifer Seiler
Gravitational-wave detectability of equal-mass black-hole binaries with aligned spins
18 pages, 11 figures, matches published version
Phys.Rev.D80:124026,2009
10.1103/PhysRevD.80.124026
null
gr-qc astro-ph.CO astro-ph.GA astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Binary black-hole systems with spins aligned or anti-aligned to the orbital angular momentum provide the natural ground to start detailed studies of the influence of strong-field spin effects on gravitational wave observations of coalescing binaries. Furthermore, such systems may be the preferred end-state of the inspiral of generic supermassive binary black-hole systems. In view of this, we have computed the inspiral and merger of a large set of binary systems of equal-mass black holes with spins parallel to the orbital angular momentum but otherwise arbitrary. Our attention is particularly focused on the gravitational-wave emission so as to quantify how much spin effects contribute to the signal-to-noise ratio, to the horizon distances, and to the relative event rates for the representative ranges in masses and detectors. As expected, the signal-to-noise ratio increases with the projection of the total black hole spin in the direction of the orbital momentum. We find that equal-spin binaries with maximum spin aligned with the orbital angular momentum are more than "three times as loud" as the corresponding binaries with anti-aligned spins, thus corresponding to event rates up to 30 times larger. We also consider the waveform mismatch between the different spinning configurations and find that, within our numerical accuracy, binaries with opposite spins S_1=-S_2 cannot be distinguished whereas binaries with spin S_1=S_2 have clearly distinct gravitational-wave emissions. Finally, we derive a simple expression for the energy radiated in gravitational waves and find that the binaries always have efficiencies E_rad/M > 3.6%, which can become as large as E_rad/M = 10% for maximally spinning binaries with spins aligned with the orbital angular momentum.
[ { "created": "Thu, 2 Jul 2009 19:11:05 GMT", "version": "v1" }, { "created": "Fri, 8 Jan 2010 10:33:55 GMT", "version": "v2" } ]
2010-01-09
[ [ "Reisswig", "Christian", "" ], [ "Husa", "Sascha", "" ], [ "Rezzolla", "Luciano", "" ], [ "Dorband", "Ernst Nils", "" ], [ "Pollney", "Denis", "" ], [ "Seiler", "Jennifer", "" ] ]
Binary black-hole systems with spins aligned or anti-aligned to the orbital angular momentum provide the natural ground to start detailed studies of the influence of strong-field spin effects on gravitational wave observations of coalescing binaries. Furthermore, such systems may be the preferred end-state of the inspiral of generic supermassive binary black-hole systems. In view of this, we have computed the inspiral and merger of a large set of binary systems of equal-mass black holes with spins parallel to the orbital angular momentum but otherwise arbitrary. Our attention is particularly focused on the gravitational-wave emission so as to quantify how much spin effects contribute to the signal-to-noise ratio, to the horizon distances, and to the relative event rates for the representative ranges in masses and detectors. As expected, the signal-to-noise ratio increases with the projection of the total black hole spin in the direction of the orbital momentum. We find that equal-spin binaries with maximum spin aligned with the orbital angular momentum are more than "three times as loud" as the corresponding binaries with anti-aligned spins, thus corresponding to event rates up to 30 times larger. We also consider the waveform mismatch between the different spinning configurations and find that, within our numerical accuracy, binaries with opposite spins S_1=-S_2 cannot be distinguished whereas binaries with spin S_1=S_2 have clearly distinct gravitational-wave emissions. Finally, we derive a simple expression for the energy radiated in gravitational waves and find that the binaries always have efficiencies E_rad/M > 3.6%, which can become as large as E_rad/M = 10% for maximally spinning binaries with spins aligned with the orbital angular momentum.
2103.11999
Hao-Jui Kuan
Hao-Jui Kuan, Daniela D. Doneva, Stoytcho S. Yazadjiev
Dynamical Formation of Scalarized Black Holes and Neutron Stars through Stellar Core Collapse
9 pages, 10 figures; accepted in PRL. This version is based on fully nonlinear simulations beyond the decoupling limit
Phys. Rev. Lett. 127, 161103 (2021)
10.1103/PhysRevLett.127.161103
null
gr-qc astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a certain class of scalar-Gauss-Bonnet gravity, the black holes and the neutron stars can undergo spontaneous scalarization -- a strong gravity phase transition triggered by a tachyonic instability due to the nonminimal coupling between the scalar field and the spacetime curvature. Studies of this phenomenon have, so far, been restricted mainly to the study of the tachyonic instability and stationary scalarized black holes and neutron stars. To date, no realistic physical mechanism for the formation of isolated scalarized black holes and neutron stars has been proposed. We study, for the first time, the spherically symmetric fully nonlinear stellar core collapse to a black hole and a neutron star in scalar-Gauss-Bonnet theories allowing for a spontaneous scalarization. We show that the core collapse can produce scalarized black holes and scalarized neutron stars starting with a nonscalarized progenitor star. The possible paths to reach the end (non)scalarized state are quite rich leading to interesting possibilities for observational manifestations.
[ { "created": "Mon, 22 Mar 2021 16:47:20 GMT", "version": "v1" }, { "created": "Wed, 13 Oct 2021 13:22:46 GMT", "version": "v2" }, { "created": "Fri, 15 Oct 2021 15:07:57 GMT", "version": "v3" } ]
2021-10-18
[ [ "Kuan", "Hao-Jui", "" ], [ "Doneva", "Daniela D.", "" ], [ "Yazadjiev", "Stoytcho S.", "" ] ]
In a certain class of scalar-Gauss-Bonnet gravity, the black holes and the neutron stars can undergo spontaneous scalarization -- a strong gravity phase transition triggered by a tachyonic instability due to the nonminimal coupling between the scalar field and the spacetime curvature. Studies of this phenomenon have, so far, been restricted mainly to the study of the tachyonic instability and stationary scalarized black holes and neutron stars. To date, no realistic physical mechanism for the formation of isolated scalarized black holes and neutron stars has been proposed. We study, for the first time, the spherically symmetric fully nonlinear stellar core collapse to a black hole and a neutron star in scalar-Gauss-Bonnet theories allowing for a spontaneous scalarization. We show that the core collapse can produce scalarized black holes and scalarized neutron stars starting with a nonscalarized progenitor star. The possible paths to reach the end (non)scalarized state are quite rich leading to interesting possibilities for observational manifestations.
1705.06705
Gregory J. Galloway
Gregory J. Galloway and Eric Ling
Topology and singularities in cosmological spacetimes obeying the null energy condition
8 pages; v2: minor changes, version to appear in CMP
null
10.1007/s00220-017-3020-9
null
gr-qc math.DG
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider globally hyperbolic spacetimes with compact Cauchy surfaces in a setting compatible with the presence of a positive cosmological constant. More specifically, for 3+1 dimensional spacetimes which satisfy the null energy condition and contain a future expanding compact Cauchy surface, we establish a precise connection between the topology of the Cauchy surfaces and the occurrence of past singularities. In addition to (a refinement of) the Penrose singularity theorem, the proof makes use of some recent advances in the topology of 3-manifolds and of certain fundamental existence results for minimal surfaces.
[ { "created": "Thu, 18 May 2017 17:22:10 GMT", "version": "v1" }, { "created": "Fri, 9 Mar 2018 22:43:58 GMT", "version": "v2" } ]
2018-03-13
[ [ "Galloway", "Gregory J.", "" ], [ "Ling", "Eric", "" ] ]
We consider globally hyperbolic spacetimes with compact Cauchy surfaces in a setting compatible with the presence of a positive cosmological constant. More specifically, for 3+1 dimensional spacetimes which satisfy the null energy condition and contain a future expanding compact Cauchy surface, we establish a precise connection between the topology of the Cauchy surfaces and the occurrence of past singularities. In addition to (a refinement of) the Penrose singularity theorem, the proof makes use of some recent advances in the topology of 3-manifolds and of certain fundamental existence results for minimal surfaces.
0912.1769
Scott Pollack
S. E. Pollack, M. D. Turner, S. Schlamminger, C. A. Hagedorn, and J. H. Gundlach
Charge Management for Gravitational Wave Observatories using UV LEDs
5 pages, submitted to PRD
Phys.Rev.D81:021101,2010
10.1103/PhysRevD.81.021101
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Accumulation of electrical charge on the end mirrors of gravitational wave observatories, such as the space-based LISA mission and ground-based LIGO detectors, can become a source of noise limiting the sensitivity of such detectors through electronic couplings to nearby surfaces. Torsion balances provide an ideal means for testing gravitational wave technologies due to their high sensitivity to small forces. Our torsion pendulum apparatus consists of a movable Au-coated Cu plate brought near a Au-coated Si plate pendulum suspended from a non-conducting quartz fiber. A UV LED located near the pendulum photoejects electrons from the surface, and a UV LED driven electron gun directs photoelectrons towards the pendulum surface. We have demonstrated both charging and discharging of the pendulum with equivalent charging rates of $\sim$$10^5 e/\mathrm{s}$, as well as spectral measurements of the pendulum charge resulting in a white noise level equivalent to $3\times10^5 e/\sqrt{Hz}$.
[ { "created": "Wed, 9 Dec 2009 15:09:02 GMT", "version": "v1" } ]
2010-04-21
[ [ "Pollack", "S. E.", "" ], [ "Turner", "M. D.", "" ], [ "Schlamminger", "S.", "" ], [ "Hagedorn", "C. A.", "" ], [ "Gundlach", "J. H.", "" ] ]
Accumulation of electrical charge on the end mirrors of gravitational wave observatories, such as the space-based LISA mission and ground-based LIGO detectors, can become a source of noise limiting the sensitivity of such detectors through electronic couplings to nearby surfaces. Torsion balances provide an ideal means for testing gravitational wave technologies due to their high sensitivity to small forces. Our torsion pendulum apparatus consists of a movable Au-coated Cu plate brought near a Au-coated Si plate pendulum suspended from a non-conducting quartz fiber. A UV LED located near the pendulum photoejects electrons from the surface, and a UV LED driven electron gun directs photoelectrons towards the pendulum surface. We have demonstrated both charging and discharging of the pendulum with equivalent charging rates of $\sim$$10^5 e/\mathrm{s}$, as well as spectral measurements of the pendulum charge resulting in a white noise level equivalent to $3\times10^5 e/\sqrt{Hz}$.
1010.0523
Milton Ruiz
Milton Ruiz, David Hilditch, Sebastiano Bernuzzi
Constraint preserving boundary conditions for the Z4c formulation of general relativity
18 pages, 8 figures
Phys.Rev.D83:024025,2011
10.1103/PhysRevD.83.024025
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss high order absorbing constraint preserving boundary conditions for the Z4c formulation of general relativity coupled to the moving puncture family of gauges. We are primarily concerned with the constraint preservation and absorption properties of these conditions. In the frozen coefficient approximation, with an appropriate first order pseudo-differential reduction, we show that the constraint subsystem is boundary stable on a four dimensional compact manifold. We analyze the remainder of the initial boundary value problem for a spherical reduction of the Z4c formulation with a particular choice of the puncture gauge. Numerical evidence for the efficacy of the conditions is presented in spherical symmetry.
[ { "created": "Mon, 4 Oct 2010 10:03:25 GMT", "version": "v1" }, { "created": "Wed, 9 Feb 2011 11:41:38 GMT", "version": "v2" } ]
2015-03-17
[ [ "Ruiz", "Milton", "" ], [ "Hilditch", "David", "" ], [ "Bernuzzi", "Sebastiano", "" ] ]
We discuss high order absorbing constraint preserving boundary conditions for the Z4c formulation of general relativity coupled to the moving puncture family of gauges. We are primarily concerned with the constraint preservation and absorption properties of these conditions. In the frozen coefficient approximation, with an appropriate first order pseudo-differential reduction, we show that the constraint subsystem is boundary stable on a four dimensional compact manifold. We analyze the remainder of the initial boundary value problem for a spherical reduction of the Z4c formulation with a particular choice of the puncture gauge. Numerical evidence for the efficacy of the conditions is presented in spherical symmetry.
gr-qc/0309006
Sanjeev S. Seahra
Sanjeev S. Seahra and Paul S. Wesson
Universes encircling 5-dimensional black holes
Reference added, 20 pages, 3 figures, REVTeX4
J.Math.Phys. 44 (2003) 5664-5680
10.1063/1.1623617
null
gr-qc hep-th
null
We clarify the status of two known solutions to the 5-dimensional vacuum Einstein field equations derived by Liu, Mashhoon & Wesson (LMW) and Fukui, Seahra & Wesson (FSW), respectively. Both 5-metrics explicitly embed 4-dimensional Friedman-Lemaitre-Robertson-Walker cosmologies with a wide range of characteristics. We show that both metrics are also equivalent to 5-dimensional topological black hole (TBH) solutions, which is demonstrated by finding explicit coordinate transformations from the TBH to LMW and FSW line elements. We argue that the equivalence is a direct consequence of Birkhoff's theorem generalized to 5 dimensions. Finally, for a special choice of parameters we plot constant coordinate surfaces of the LMW patch in a Penrose-Carter diagram. This shows that the LMW coordinates are regular across the black and/or white hole horizons.
[ { "created": "Mon, 1 Sep 2003 20:34:38 GMT", "version": "v1" }, { "created": "Wed, 7 Jan 2004 15:50:18 GMT", "version": "v2" } ]
2009-11-10
[ [ "Seahra", "Sanjeev S.", "" ], [ "Wesson", "Paul S.", "" ] ]
We clarify the status of two known solutions to the 5-dimensional vacuum Einstein field equations derived by Liu, Mashhoon & Wesson (LMW) and Fukui, Seahra & Wesson (FSW), respectively. Both 5-metrics explicitly embed 4-dimensional Friedman-Lemaitre-Robertson-Walker cosmologies with a wide range of characteristics. We show that both metrics are also equivalent to 5-dimensional topological black hole (TBH) solutions, which is demonstrated by finding explicit coordinate transformations from the TBH to LMW and FSW line elements. We argue that the equivalence is a direct consequence of Birkhoff's theorem generalized to 5 dimensions. Finally, for a special choice of parameters we plot constant coordinate surfaces of the LMW patch in a Penrose-Carter diagram. This shows that the LMW coordinates are regular across the black and/or white hole horizons.
gr-qc/0611083
Francisco Lobo
Francisco S. N. Lobo, Aaron V. B. Arellano
Gravastars supported by nonlinear electrodynamics
23 pages, 10 figures, LaTeX2e, IOP style files. V2: considerable changes, references added; to appear in Class. Quant. Gravity
Class.Quant.Grav.24:1069-1088,2007
10.1088/0264-9381/24/5/004
null
gr-qc astro-ph hep-th
null
Gravastar models have recently been proposed as an alternative to black holes, mainly to avoid the problematic issues associated with event horizons and singularities. In this work, a wide variety of gravastar models within the context of nonlinear electrodynamics are constructed. Using the $F$ representation, specific forms of Lagrangians are considered describing magnetic gravastars, which may be interpreted as self-gravitating magnetic monopoles with charge $g$. Using the dual $P$ formulation of nonlinear electrodynamics, electric gravastar models are constructed by considering specific structural functions, and the characteristics and physical properties of the solutions are further explored. These interior nonlinear electrodynamic geometries are matched to an exterior Schwarzschild spacetime at a junction interface.
[ { "created": "Wed, 15 Nov 2006 11:21:49 GMT", "version": "v1" }, { "created": "Mon, 22 Jan 2007 17:26:43 GMT", "version": "v2" }, { "created": "Tue, 23 Jan 2007 10:25:39 GMT", "version": "v3" } ]
2008-11-26
[ [ "Lobo", "Francisco S. N.", "" ], [ "Arellano", "Aaron V. B.", "" ] ]
Gravastar models have recently been proposed as an alternative to black holes, mainly to avoid the problematic issues associated with event horizons and singularities. In this work, a wide variety of gravastar models within the context of nonlinear electrodynamics are constructed. Using the $F$ representation, specific forms of Lagrangians are considered describing magnetic gravastars, which may be interpreted as self-gravitating magnetic monopoles with charge $g$. Using the dual $P$ formulation of nonlinear electrodynamics, electric gravastar models are constructed by considering specific structural functions, and the characteristics and physical properties of the solutions are further explored. These interior nonlinear electrodynamic geometries are matched to an exterior Schwarzschild spacetime at a junction interface.
1004.1760
Sun ChengYi
Cheng-Yi Sun
Trapping Horizons in the Sultana-Dyer Space-Time
no figures, 5 pages; PCAS and key words are added
Commun.Theor.Phys.55:597-598,2011
10.1088/0253-6102/55/4/13
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Sultana-Dyer space-time is suggested as a model describing a black hole embedded in an expanding universe. Recently, in \cite{0705.4012}, its global structure is analyzed and the trapping horizons are shown. In the paper, by directly calculating the expansions of the radial null vector fields normal to the space-like two-spheres foliating the trapping horizons, we find that the trapping horizon outside the event horizon in the Sultana-Dyer space-time is a past trapping horizon. Further, we find that the past trapping horizon is an outer, instantaneously degenerate or inner trapping horizon accordingly when the radial coordinate is less than, equal to or greater than some value.
[ { "created": "Sun, 11 Apr 2010 04:35:23 GMT", "version": "v1" }, { "created": "Mon, 19 Apr 2010 06:26:10 GMT", "version": "v2" }, { "created": "Sat, 29 May 2010 05:44:36 GMT", "version": "v3" } ]
2011-05-05
[ [ "Sun", "Cheng-Yi", "" ] ]
The Sultana-Dyer space-time is suggested as a model describing a black hole embedded in an expanding universe. Recently, in \cite{0705.4012}, its global structure is analyzed and the trapping horizons are shown. In the paper, by directly calculating the expansions of the radial null vector fields normal to the space-like two-spheres foliating the trapping horizons, we find that the trapping horizon outside the event horizon in the Sultana-Dyer space-time is a past trapping horizon. Further, we find that the past trapping horizon is an outer, instantaneously degenerate or inner trapping horizon accordingly when the radial coordinate is less than, equal to or greater than some value.
1705.07703
Javad Taghizadeh Firouzjaee
Abasalt Rostami and Javad T. Firouzjaee
Quantum decoherence from entanglement during inflation
11 pages
null
null
null
gr-qc astro-ph.CO hep-th quant-ph
http://creativecommons.org/licenses/by/4.0/
We study the primary entanglement effect on the decoherence of fields reduced density matrix which are in interaction with another fields or independent mode functions. We show that the primary entanglement has a significant role in decoherence of the system quantum state. We find that the existence of entanglement could couple dynamical equations coming from Schr\"{o}dinger equation. We show if one wants to see no effect of the entanglement parameter in decoherence then interaction terms in Hamiltonian can not be independent from each other. Generally, including the primary entanglement destroys the independence of the interaction terms. Our results could be generalized to every scalar quantum field theory with a well defined quantization in a given curved space time.
[ { "created": "Mon, 22 May 2017 13:09:30 GMT", "version": "v1" } ]
2017-05-23
[ [ "Rostami", "Abasalt", "" ], [ "Firouzjaee", "Javad T.", "" ] ]
We study the primary entanglement effect on the decoherence of fields reduced density matrix which are in interaction with another fields or independent mode functions. We show that the primary entanglement has a significant role in decoherence of the system quantum state. We find that the existence of entanglement could couple dynamical equations coming from Schr\"{o}dinger equation. We show if one wants to see no effect of the entanglement parameter in decoherence then interaction terms in Hamiltonian can not be independent from each other. Generally, including the primary entanglement destroys the independence of the interaction terms. Our results could be generalized to every scalar quantum field theory with a well defined quantization in a given curved space time.
2207.07060
Valerio Faraoni
Reza Saadati, Andrea Giusti, Valerio Faraoni, Fatimah Shojai
New time-dependent solutions of viable Horndeski gravity
17 pages, 2 figures
null
10.1088/1475-7516/2022/09/067
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We generate new spherical and time-dependent solutions of viable Horndeski gravity by disforming a solution of the Einstein equations with scalar field source and positive cosmological constant. They describe dynamical objects embedded in asymptotically FLRW spacetimes and contain apparent horizons and a finite radius singularity that evolve in time in peculiar ways apparently not encountered before in Einstein and "old" scalar-tensor gravity.
[ { "created": "Thu, 14 Jul 2022 16:59:22 GMT", "version": "v1" } ]
2022-10-05
[ [ "Saadati", "Reza", "" ], [ "Giusti", "Andrea", "" ], [ "Faraoni", "Valerio", "" ], [ "Shojai", "Fatimah", "" ] ]
We generate new spherical and time-dependent solutions of viable Horndeski gravity by disforming a solution of the Einstein equations with scalar field source and positive cosmological constant. They describe dynamical objects embedded in asymptotically FLRW spacetimes and contain apparent horizons and a finite radius singularity that evolve in time in peculiar ways apparently not encountered before in Einstein and "old" scalar-tensor gravity.
2402.13014
A. Yu. Petrov
A. A. Ara\'ujo Filho, J. R. Nascimento, A. Yu. Petrov, P. J. Porf\'irio
An exact stationary axisymmetric vacuum solution within a metric--affine bumblebee gravity
36 pages, version accepted to JCAP
JCAP07(2024)004
10.1088/1475-7516/2024/07/004
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within the framework of the spontaneous Lorentz symmetry breaking, we consider a metric--affine generalization of the gravitational sector of the Standard--Model Extension (SME), including the Lorentz--violating (LV) coefficients $u$ and $s^{\mu\nu}$. In this model, we derive the modified Einstein field equations in order to obtain a new axisymmetric vacuum spinning solution for a particular bumblebee's profile. Such a solution has the remarkable property of incorporating the effects of Lorentz symmetry breaking (LSB) through the LV dimensionless parameter $X=\xi b^2$, as the LSB is turned off, $X=0$, we recover the well--established result, the Kerr solution, as expected. Afterwards, we calculate the geodesics, the radial acceleration and thermodynamic quantities for this new metric. We also estimate an upper bound for $X$ by using astrophysical data of the advance Mercury's perihelion.
[ { "created": "Tue, 20 Feb 2024 13:57:23 GMT", "version": "v1" }, { "created": "Mon, 10 Jun 2024 16:20:40 GMT", "version": "v2" } ]
2024-07-03
[ [ "Filho", "A. A. Araújo", "" ], [ "Nascimento", "J. R.", "" ], [ "Petrov", "A. Yu.", "" ], [ "Porfírio", "P. J.", "" ] ]
Within the framework of the spontaneous Lorentz symmetry breaking, we consider a metric--affine generalization of the gravitational sector of the Standard--Model Extension (SME), including the Lorentz--violating (LV) coefficients $u$ and $s^{\mu\nu}$. In this model, we derive the modified Einstein field equations in order to obtain a new axisymmetric vacuum spinning solution for a particular bumblebee's profile. Such a solution has the remarkable property of incorporating the effects of Lorentz symmetry breaking (LSB) through the LV dimensionless parameter $X=\xi b^2$, as the LSB is turned off, $X=0$, we recover the well--established result, the Kerr solution, as expected. Afterwards, we calculate the geodesics, the radial acceleration and thermodynamic quantities for this new metric. We also estimate an upper bound for $X$ by using astrophysical data of the advance Mercury's perihelion.
gr-qc/0509081
Gaurav Khanna
Seth Connors, Gaurav Khanna
Approximate pre-classical solutions in loop quantum cosmology
10 pages, 5 figures
Class.Quant.Grav.23:2919-2926,2006
10.1088/0264-9381/23/9/009
null
gr-qc
null
In this paper we introduce a numerical approximation technique to obtain pre-classical solutions to models of loop quantum gravity. In particular, we apply the technique to vacuum Bianchi I cosmological models and recover known solutions. We also present a pre-classical solution to the Bianchi I LRS model with cosmological constant, which has not appeared elsewhere.
[ { "created": "Tue, 20 Sep 2005 21:14:19 GMT", "version": "v1" } ]
2014-11-17
[ [ "Connors", "Seth", "" ], [ "Khanna", "Gaurav", "" ] ]
In this paper we introduce a numerical approximation technique to obtain pre-classical solutions to models of loop quantum gravity. In particular, we apply the technique to vacuum Bianchi I cosmological models and recover known solutions. We also present a pre-classical solution to the Bianchi I LRS model with cosmological constant, which has not appeared elsewhere.
1904.09260
Lo\"ic Marsot
Lo\"ic Marsot
How does the photon's spin affect Gravitational Wave measurements?
12 pages; version 2 matches publication with an improved introduction, 14 pages
Phys. Rev. D 100, 064050 (2019)
10.1103/PhysRevD.100.064050
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the effect of the polarization of light beams on the time delay measured in Gravitational Wave experiments. To this end, we consider the Mathisson-Papapetrou-Dixon equations in a gravitational wave background, with two of the possible spin supplementary conditions: by Frenkel-Pirani, or by Tulczyjew. In the first case, photons follow a null geodesic and thus no spin effect is present. The second case shows a deviation of the photons from the null geodesic, resulting in a tiny effect on the measured time delay of photons depending on their polarization state.
[ { "created": "Fri, 19 Apr 2019 16:42:09 GMT", "version": "v1" }, { "created": "Wed, 25 Sep 2019 13:07:12 GMT", "version": "v2" } ]
2019-10-02
[ [ "Marsot", "Loïc", "" ] ]
We study the effect of the polarization of light beams on the time delay measured in Gravitational Wave experiments. To this end, we consider the Mathisson-Papapetrou-Dixon equations in a gravitational wave background, with two of the possible spin supplementary conditions: by Frenkel-Pirani, or by Tulczyjew. In the first case, photons follow a null geodesic and thus no spin effect is present. The second case shows a deviation of the photons from the null geodesic, resulting in a tiny effect on the measured time delay of photons depending on their polarization state.
gr-qc/0501006
Hernando Quevedo
Hernando Quevedo
Pioneer's Anomaly and the Solar Quadrupole Moment
Typos corrected, references added
null
10.1063/1.1900512
null
gr-qc
null
The trajectories of test particles moving in the gravitational field of a non-spherically symmetric mass distribution become affected by the presence of multipole moments. In the case of hyperbolic trajectories, the quadrupole moment of an oblate mass induces a displacement of the trajectory towards the mass source, an effect that can be interpreted as an additional acceleration directed towards the source. Although this additional acceleration is not constant, we perform a general relativistic analysis in order to evaluate the possibility of explaining Pioneer's anomalous acceleration by means of the observed Solar quadrupole moment, within the range of accuracy of the observed anomalous acceleration. We conclude that the Solar quadrupole moment generates an acceleration which is of the same order of magnitude of Pioneer's constant acceleration only at distances of a few astronomical units.
[ { "created": "Tue, 4 Jan 2005 05:16:28 GMT", "version": "v1" }, { "created": "Mon, 23 May 2005 23:56:16 GMT", "version": "v2" } ]
2009-11-11
[ [ "Quevedo", "Hernando", "" ] ]
The trajectories of test particles moving in the gravitational field of a non-spherically symmetric mass distribution become affected by the presence of multipole moments. In the case of hyperbolic trajectories, the quadrupole moment of an oblate mass induces a displacement of the trajectory towards the mass source, an effect that can be interpreted as an additional acceleration directed towards the source. Although this additional acceleration is not constant, we perform a general relativistic analysis in order to evaluate the possibility of explaining Pioneer's anomalous acceleration by means of the observed Solar quadrupole moment, within the range of accuracy of the observed anomalous acceleration. We conclude that the Solar quadrupole moment generates an acceleration which is of the same order of magnitude of Pioneer's constant acceleration only at distances of a few astronomical units.
gr-qc/0602061
Ouali Taoufik
A. Errahmani, T. Ouali
High energy description of dark energy in an approximate 3-brane Brans-Dicke cosmology
9 pages
Phys.Lett. B641 (2006) 357-361
10.1016/j.physletb.2006.08.063
null
gr-qc
null
We consider a Brans-Dicke cosmology in five-dimensional space-time. Neglecting the quadratic and the mixed Brans-Dicke terms in the Einstein equation, we derive a modified wave equation of the Brans-Dicke field. We show that, at high energy limit, the 3-brane Brans-Dicke cosmology could be described as the standard one by changing the equation of state. Finally as an illustration of the purpose, we show that the dark energy component of the universe agrees with the observations data.
[ { "created": "Wed, 15 Feb 2006 13:39:43 GMT", "version": "v1" }, { "created": "Thu, 20 Apr 2006 11:53:51 GMT", "version": "v2" } ]
2009-11-11
[ [ "Errahmani", "A.", "" ], [ "Ouali", "T.", "" ] ]
We consider a Brans-Dicke cosmology in five-dimensional space-time. Neglecting the quadratic and the mixed Brans-Dicke terms in the Einstein equation, we derive a modified wave equation of the Brans-Dicke field. We show that, at high energy limit, the 3-brane Brans-Dicke cosmology could be described as the standard one by changing the equation of state. Finally as an illustration of the purpose, we show that the dark energy component of the universe agrees with the observations data.
gr-qc/0609081
Ignazio Ciufolini
Ignazio Ciufolini
On the orbit of the LARES satellite
null
null
null
null
gr-qc
null
This paper is motivated by the recent possibility to find an inexpensive launching vehicle for the LARES satellite, however at an altitude much lower than originally planned for the LAGEOS III/LARES satellite. We present here a preliminary error analysis corresponding to a lower, quasi-polar, orbit, in particular we analyze the effect on the LARES node of the Earth's static gravitational field, and in particular of the Earth's even zonal harmonics, the effect of the time dependent Earth's gravitational field, and in particular of the K1 tide, and the effect of particle drag.
[ { "created": "Wed, 20 Sep 2006 15:01:53 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ciufolini", "Ignazio", "" ] ]
This paper is motivated by the recent possibility to find an inexpensive launching vehicle for the LARES satellite, however at an altitude much lower than originally planned for the LAGEOS III/LARES satellite. We present here a preliminary error analysis corresponding to a lower, quasi-polar, orbit, in particular we analyze the effect on the LARES node of the Earth's static gravitational field, and in particular of the Earth's even zonal harmonics, the effect of the time dependent Earth's gravitational field, and in particular of the K1 tide, and the effect of particle drag.
1905.09671
Adam Balcerzak
Adam Balcerzak and Konrad Marosek
Emergence of multiverse in third quantized varying constants cosmologies
6 pages, 2 figures
Eur. Phys. J. C (2019) 79: 563
10.1140/epjc/s10052-019-7069-9
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Although the standard cosmological model explains most of the observed phenomena it still struggles with the problem of initial singularity. An interesting scenario in which the problem of the initial singularity is somehow circumvented was proposed in the context of string theory where the canonical quantisation procedure was additionally applied. A similar effect can be achieved in the context of the canonically quantized theory with varying speed of light and varying gravitational constant where both quantities are represented by non-minimally coupled scalar fields. Such theory contains both the pre-big-bang contracting phase and the post-big-bang expanding phase and predicts non-vanishing probability of the transition from the former to the latter phase. In this paper we quantize such a theory once again by applying the third quantization scheme and show that the resulting theory contains scenario in which the whole multiverse is created from nothing. The generated family of the universes is described by the Bose-Einstein distribution.
[ { "created": "Thu, 23 May 2019 14:13:51 GMT", "version": "v1" }, { "created": "Fri, 24 May 2019 13:21:22 GMT", "version": "v2" }, { "created": "Wed, 3 Jul 2019 17:24:38 GMT", "version": "v3" } ]
2019-07-04
[ [ "Balcerzak", "Adam", "" ], [ "Marosek", "Konrad", "" ] ]
Although the standard cosmological model explains most of the observed phenomena it still struggles with the problem of initial singularity. An interesting scenario in which the problem of the initial singularity is somehow circumvented was proposed in the context of string theory where the canonical quantisation procedure was additionally applied. A similar effect can be achieved in the context of the canonically quantized theory with varying speed of light and varying gravitational constant where both quantities are represented by non-minimally coupled scalar fields. Such theory contains both the pre-big-bang contracting phase and the post-big-bang expanding phase and predicts non-vanishing probability of the transition from the former to the latter phase. In this paper we quantize such a theory once again by applying the third quantization scheme and show that the resulting theory contains scenario in which the whole multiverse is created from nothing. The generated family of the universes is described by the Bose-Einstein distribution.
1710.02327
LIGO Scientific Collaboration and Virgo Collaboration
The LIGO Scientific Collaboration and the Virgo Collaboration: B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Afrough, B. Agarwal, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. Aguiar, L. Aiello, A. Ain, B. Allen, G. Allen, A. Allocca, P. A. Altin, A. Amato, A. Ananyeva, S. B. Anderson, W. G. Anderson, S. V. Angelova, S. Antier, S. Appert, K. Arai, M. C. Araya, J. S. Areeda, N. Arnaud, K. G. Arun, S. Ascenzi, G. Ashton, M. Ast, S. M. Aston, P. Astone, D. V. Atallah, P. Aufmuth, C. Aulbert, K. AultONeal, C. Austin, A. Avila-Alvarez, S. Babak, P. Bacon, M. K. M. Bader, S. Bae, P. T. Baker, F. Baldaccini, G. Ballardin, S. W. Ballmer, S. Banagiri, J. C. Barayoga, S. E. Barclay, B. C. Barish, D. Barker, K. Barkett, F. Barone, B. Barr, L. Barsotti, M. Barsuglia, D. Barta, J. Bartlett, I. Bartos, R. Bassiri, A. Basti, J. C. Batch, M. Bawaj, J. C. Bayley, M. Bazzan, B. B\'ecsy, C. Beer, M. Bejger, I. Belahcene, A. S. Bell, B. K. Berger, G. Bergmann, J. J. Bero, C. P. L. Berry, D. Bersanetti, A. Bertolini, J. Betzwieser, S. Bhagwat, R. Bhandare, I. A. Bilenko, G. Billingsley, C. R. Billman, J. Birch, R. Birney, O. Birnholtz, S. Biscans, S. Biscoveanu, A. Bisht, M. Bitossi, C. Biwer, M. A. Bizouard, J. K. Blackburn, J. Blackman, C. D. Blair, D. G. Blair, R. M. Blair, S. Bloemen, O. Bock, N. Bode, M. Boer, G. Bogaert, A. Bohe, F. Bondu, E. Bonilla, R. Bonnand, B. A. Boom, R. Bork, V. Boschi, S. Bose, K. Bossie, Y. Bouffanais, A. Bozzi, C. Bradaschia, P. R. Brady, M. Branchesi, J. E. Brau, T. Briant, A. Brillet, M. Brinkmann, V. Brisson, P. Brockill, J. E. Broida, A. F. Brooks, D. A. Brown, D. D. Brown, S. Brunett, C. C. Buchanan, A. Buikema, T. Bulik, H. J. Bulten, A. Buonanno, D. Buskulic, C. Buy, R. L. Byer, M. Cabero, L. Cadonati, G. Cagnoli, C. Cahillane, J. Calder'on Bustillo, T. A. Callister, E. Calloni, J. B. Camp, P. Canizares, K. C. Cannon, H. Cao, J. Cao, C. D. Capano, E. Capocasa, F. Carbognani, S. Caride, M. F. Carney, J. Casanueva Diaz, C. Casentini, S. Caudill, M. Cavagli\`a, F. Cavalier, R. Cavalieri, G. Cella, C. B. Cepeda, P. Cerd'a-Dur'an, G. Cerretani, E. Cesarini, S. J. Chamberlin, M. Chan, S. Chao, P. Charlton, E. Chase, E. Chassande-Mottin, D. Chatterjee, B. D. Cheeseboro, H. Y. Chen, X. Chen, Y. Chen, H.-P. Cheng, H. Chia, A. Chincarini, A. Chiummo, T. Chmiel, H. S. Cho, M. Cho, J. H. Chow, N. Christensen, Q. Chu, A. J. K. Chua, S. Chua, A. K. W. Chung, S. Chung, G. Ciani, R. Ciolfi, C. E. Cirelli, A. Cirone, F. Clara, J. A. Clark, P. Clearwater, F. Cleva, C. Cocchieri, E. Coccia, P.-F. Cohadon, D. Cohen, A. Colla, C. G. Collette, L. R. Cominsky, M. Constancio Jr., L. Conti, S. J. Cooper, P. Corban, T. R. Corbitt, I. Cordero-Carri'on, K. R. Corley, N. Cornish, A. Corsi, S. Cortese, C. A. Costa, M. W. Coughlin, S. B. Coughlin, J.-P. Coulon, S. T. Countryman, P. Couvares, P. B. Covas, E. E. Cowan, D. M. Coward, M. J. Cowart, D. C. Coyne, R. Coyne, J. D. E. Creighton, T. D. Creighton, J. Cripe, S. G. Crowder, T. J. Cullen, A. Cumming, L. Cunningham, E. Cuoco, T. Dal Canton, G. D'alya, S. L. Danilishin, S. D'Antonio, K. Danzmann, A. Dasgupta, C. F. Da Silva Costa, V. Dattilo, I. Dave, M. Davier, D. Davis, E. J. Daw, B. Day, S. De, D. DeBra, J. Degallaix, M. De Laurentis, S. Del'eglise, W. Del Pozzo, N. Demos, T. Denker, T. Dent, R. De Pietri, V. Dergachev, R. De Rosa, R. T. DeRosa, C. De Rossi, R. DeSalvo, O. de Varona, J. Devenson, S. Dhurandhar, M. C. D'iaz, L. Di Fiore, M. Di Giovanni, T. Di Girolamo, A. Di Lieto, S. Di Pace, I. Di Palma, F. Di Renzo, Z. Doctor, V. Dolique, F. Donovan, K. L. Dooley, S. Doravari, I. Dorrington, R. Douglas, M. Dovale 'Alvarez, T. P. Downes, M. Drago, C. Dreissigacker, J. C. Driggers, Z. Du, M. Ducrot, P. Dupej, S. E. Dwyer, T. B. Edo, M. C. Edwards, A. Effler, H.-B. Eggenstein, P. Ehrens, J. Eichholz, S. S. Eikenberry, R. A. Eisenstein, R. C. Essick, D. Estevez, Z. B. Etienne, T. Etzel, M. Evans, T. M. Evans, M. Factourovich, V. Fafone, H. Fair, S. Fairhurst, X. Fan, S. Farinon, B. Farr, W. M. Farr, E. J. Fauchon-Jones, M. Favata, M. Fays, C. Fee, H. Fehrmann, J. Feicht, M. M. Fejer, A. Fernandez-Galiana, I. Ferrante, E. C. Ferreira, F. Ferrini, F. Fidecaro, D. Finstad, I. Fiori, D. Fiorucci, M. Fishbach, R. P. Fisher, M. Fitz-Axen, R. Flaminio, M. Fletcher, H. Fong, J. A. Font, P. W. F. Forsyth, S. S. Forsyth, J.-D. Fournier, S. Frasca, F. Frasconi, Z. Frei, A. Freise, R. Frey, V. Frey, E. M. Fries, P. Fritschel, V. V. Frolov, P. Fulda, M. Fyffe, H. Gabbard, B. U. Gadre, S. M. Gaebel, J. R. Gair, L. Gammaitoni, M. R. Ganija, S. G. Gaonkar, C. Garcia-Quiros, F. Garufi, B. Gateley, S. Gaudio, G. Gaur, V. Gayathri, N. Gehrels, G. Gemme, E. Genin, A. Gennai, D. George, J. George, L. Gergely, V. Germain, S. Ghonge, Abhirup Ghosh, Archisman Ghosh, S. Ghosh, J. A. Giaime, K. D. Giardina, A. Giazotto, K. Gill, L. Glover, E. Goetz, R. Goetz, S. Gomes, B. Goncharov, G. Gonz'alez, J. M. Gonzalez Castro, A. Gopakumar, M. L. Gorodetsky, S. E. Gossan, M. Gosselin, R. Gouaty, A. Grado, C. Graef, M. Granata, A. Grant, S. Gras, C. Gray, G. Greco, A. C. Green, E. M. Gretarsson, P. Groot, H. Grote, S. Grunewald, P. Gruning, G. M. Guidi, X. Guo, A. Gupta, M. K. Gupta, K. E. Gushwa, E. K. Gustafson, R. Gustafson, O. Halim, B. R. Hall, E. D. Hall, E. Z. Hamilton, G. Hammond, M. Haney, M. M. Hanke, J. Hanks, C. Hanna, M. D. Hannam, O. A. Hannuksela, J. Hanson, T. Hardwick, J. Harms, G. M. Harry, I. W. Harry, M. J. Hart, C.-J. Haster, K. Haughian, J. Healy, A. Heidmann, M. C. Heintze, H. Heitmann, P. Hello, G. Hemming, M. Hendry, I. S. Heng, J. Hennig, A. W. Heptonstall, M. Heurs, S. Hild, T. Hinderer, W. C. G. Ho, D. Hoak, D. Hofman, K. Holt, D. E. Holz, P. Hopkins, C. Horst, J. Hough, E. A. Houston, E. J. Howell, A. Hreibi, Y. M. Hu, E. A. Huerta, D. Huet, B. Hughey, S. Husa, S. H. Huttner, T. Huynh-Dinh, N. Indik, R. Inta, G. Intini, H. N. Isa, J.-M. Isac, M. Isi, B. R. Iyer, K. Izumi, T. Jacqmin, K. Jani, P. Jaranowski, S. Jawahar, F. Jim'enez-Forteza, W. W. Johnson, D. I. Jones, R. Jones, R. J. G. Jonker, L. Ju, J. Junker, C. V. Kalaghatgi, V. Kalogera, B. Kamai, S. Kandhasamy, G. Kang, J. B. Kanner, S. J. Kapadia, S. Karki, K. S. Karvinen, M. Kasprzack, M. Katolik, E. Katsavounidis, W. Katzman, S. Kaufer, K. Kawabe, F. K'ef'elian, D. Keitel, A. J. Kemball, R. Kennedy, C. Kent, J. S. Key, F. Y. Khalili, I. Khan, S. Khan, Z. Khan, E. A. Khazanov, N. Kijbunchoo, Chunglee Kim, J. C. Kim, K. Kim, W. Kim, W. S. Kim, Y.-M. Kim, S. J. Kimbrell, E. J. King, P. J. King, M. Kinley-Hanlon, R. Kirchhoff, J. S. Kissel, L. Kleybolte, S. Klimenko, T. D. Knowles, P. Koch, S. M. Koehlenbeck, S. Koley, V. Kondrashov, A. Kontos, M. Korobko, W. Z. Korth, I. Kowalska, D. B. Kozak, C. Kr"amer, V. Kringel, B. Krishnan, A. Kr'olak, G. Kuehn, P. Kumar, R. Kumar, S. Kumar, L. Kuo, A. Kutynia, S. Kwang, B. D. Lackey, K. H. Lai, M. Landry, R. N. Lang, J. Lange, B. Lantz, R. K. Lanza, A. Lartaux-Vollard, P. D. Lasky, M. Laxen, A. Lazzarini, C. Lazzaro, P. Leaci, S. Leavey, C. H. Lee, H. K. Lee, H. M. Lee, H. W. Lee, K. Lee, J. Lehmann, A. Lenon, M. Leonardi, N. Leroy, N. Letendre, Y. Levin, T. G. F. Li, S. D. Linker, T. B. Littenberg, J. Liu, R. K. L. Lo, N. A. Lockerbie, L. T. London, J. E. Lord, M. Lorenzini, V. Loriette, M. Lormand, G. Losurdo, J. D. Lough, G. Lovelace, H. L\"uck, D. Lumaca, A. P. Lundgren, R. Lynch, Y. Ma, R. Macas, S. Macfoy, B. Machenschalk, M. MacInnis, D. M. Macleod, I. Maga\~na Hernandez, F. Maga\~na-Sandoval, L. Maga\~na Zertuche, R. M. Magee, E. Majorana, I. Maksimovic, N. Man, V. Mandic, V. Mangano, G. L. Mansell, M. Manske, M. Mantovani, F. Marchesoni, F. Marion, S. M'arka, Z. M'arka, C. Markakis, A. S. Markosyan, A. Markowitz, E. Maros, A. Marquina, F. Martelli, L. Martellini, I. W. Martin, R. M. Martin, D. V. Martynov, K. Mason, E. Massera, A. Masserot, T. J. Massinger, M. Masso-Reid, S. Mastrogiovanni, A. Matas, F. Matichard, L. Matone, N. Mavalvala, N. Mazumder, R. McCarthy, D. E. McClelland, S. McCormick, L. McCuller, S. C. McGuire, G. McIntyre, J. McIver, D. J. McManus, L. McNeill, T. McRae, S. T. McWilliams, D. Meacher, G. D. Meadors, M. Mehmet, J. Meidam, E. Mejuto-Villa, A. Melatos, G. Mendell, R. A. Mercer, E. L. Merilh, M. Merzougui, S. Meshkov, C. Messenger, C. Messick, R. Metzdorff, P. M. Meyers, H. Miao, C. Michel, H. Middleton, E. E. Mikhailov, L. Milano, A. L. Miller, B. B. Miller, J. Miller, M. Millhouse, M. C. Milovich-Goff, O. Minazzoli, Y. Minenkov, J. Ming, C. Mishra, S. Mitra, V. P. Mitrofanov, G. Mitselmakher, R. Mittleman, D. Moffa, A. Moggi, K. Mogushi, M. Mohan, S. R. P. Mohapatra, M. Montani, C. J. Moore, D. Moraru, G. Moreno, S. R. Morriss, B. Mours, C. M. Mow-Lowry, G. Mueller, A. W. Muir, Arunava Mukherjee, D. Mukherjee, S. Mukherjee, N. Mukund, A. Mullavey, J. Munch, E. A. Mu\~niz, M. Muratore, P. G. Murray, K. Napier, I. Nardecchia, L. Naticchioni, R. K. Nayak, J. Neilson, G. Nelemans, T. J. N. Nelson, M. Nery, A. Neunzert, L. Nevin, J. M. Newport, G. Newton, K. K. Y. Ng, T. T. Nguyen, D. Nichols, A. B. Nielsen, S. Nissanke, A. Nitz, A. Noack, F. Nocera, D. Nolting, C. North, L. K. Nuttall, J. Oberling, G. D. O'Dea, G. H. Ogin, J. J. Oh, S. H. Oh, F. Ohme, M. A. Okada, M. Oliver, P. Oppermann, Richard J. Oram, B. O'Reilly, R. Ormiston, L. F. Ortega, R. O'Shaughnessy, S. Ossokine, D. J. Ottaway, H. Overmier, B. J. Owen, A. E. Pace, J. Page, M. A. Page, A. Pai, S. A. Pai, J. R. Palamos, O. Palashov, C. Palomba, A. Pal-Singh, Howard Pan, Huang-Wei Pan, B. Pang, P. T. H. Pang, C. Pankow, F. Pannarale, B. C. Pant, F. Paoletti, A. Paoli, M. A. Papa, A. Parida, W. Parker, D. Pascucci, A. Pasqualetti, R. Passaquieti, D. Passuello, M. Patil, B. Patricelli, B. L. Pearlstone, M. Pedraza, R. Pedurand, L. Pekowsky, A. Pele, S. Penn, C. J. Perez, A. Perreca, L. M. Perri, H. P. Pfeiffer, M. Phelps, O. J. Piccinni, M. Pichot, F. Piergiovanni, V. Pierro, G. Pillant, L. Pinard, I. M. Pinto, M. Pirello, M. Pitkin, M. Poe, R. Poggiani, P. Popolizio, E. K. Porter, A. Post, J. Powell, J. Prasad, J. W. W. Pratt, G. Pratten, V. Predoi, T. Prestegard, M. Prijatelj, M. Principe, S. Privitera, G. A. Prodi, L. G. Prokhorov, O. Puncken, M. Punturo, P. Puppo, M. P"urrer, H. Qi, V. Quetschke, E. A. Quintero, R. Quitzow-James, F. J. Raab, D. S. Rabeling, H. Radkins, P. Raffai, S. Raja, C. Rajan, B. Rajbhandari, M. Rakhmanov, K. E. Ramirez, A. Ramos-Buades, P. Rapagnani, V. Raymond, M. Razzano, J. Read, T. Regimbau, L. Rei, S. Reid, D. H. Reitze, W. Ren, S. D. Reyes, F. Ricci, P. M. Ricker, S. Rieger, K. Riles, M. Rizzo, N. A. Robertson, R. Robie, F. Robinet, A. Rocchi, L. Rolland, J. G. Rollins, V. J. Roma, R. Romano, C. L. Romel, J. H. Romie, D. Rosi'nska, M. P. Ross, S. Rowan, A. R"udiger, P. Ruggi, G. Rutins, K. Ryan, S. Sachdev, T. Sadecki, L. Sadeghian, M. Sakellariadou, L. Salconi, M. Saleem, F. Salemi, A. Samajdar, L. Sammut, L. M. Sampson, E. J. Sanchez, L. E. Sanchez, N. Sanchis-Gual, V. Sandberg, J. R. Sanders, B. Sassolas, B. S. Sathyaprakash, P. R. Saulson, O. Sauter, R. L. Savage, A. Sawadsky, P. Schale, M. Scheel, J. Scheuer, J. Schmidt, P. Schmidt, R. Schnabel, R. M. S. Schofield, A. Sch"onbeck, E. Schreiber, D. Schuette, B. W. Schulte, B. F. Schutz, S. G. Schwalbe, J. Scott, S. M. Scott, E. Seidel, D. Sellers, A. S. Sengupta, D. Sentenac, V. Sequino, A. Sergeev, D. A. Shaddock, T. J. Shaffer, A. A. Shah, M. S. Shahriar, M. B. Shaner, L. Shao, B. Shapiro, P. Shawhan, A. Sheperd, D. H. Shoemaker, D. M. Shoemaker, K. Siellez, X. Siemens, M. Sieniawska, D. Sigg, A. D. Silva, L. P. Singer, A. Singh, A. Singhal, A. M. Sintes, B. J. J. Slagmolen, B. Smith, J. R. Smith, R. J. E. Smith, S. Somala, E. J. Son, J. A. Sonnenberg, B. Sorazu, F. Sorrentino, T. Souradeep, A. P. Spencer, A. K. Srivastava, K. Staats, A. Staley, M. Steinke, J. Steinlechner, S. Steinlechner, D. Steinmeyer, S. P. Stevenson, R. Stone, D. J. Stops, K. A. Strain, G. Stratta, S. E. Strigin, A. Strunk, R. Sturani, A. L. Stuver, T. Z. Summerscales, L. Sun, S. Sunil, J. Suresh, P. J. Sutton, B. L. Swinkels, M. J. Szczepa'nczyk, M. Tacca, S. C. Tait, C. Talbot, D. Talukder, D. B. Tanner, M. T'apai, A. Taracchini, J. D. Tasson, J. A. Taylor, R. Taylor, S. V. Tewari, T. Theeg, F. Thies, E. G. Thomas, M. Thomas, P. Thomas, K. A. Thorne, E. Thrane, S. Tiwari, V. Tiwari, K. V. Tokmakov, K. Toland, M. Tonelli, Z. Tornasi, A. Torres-Forn'e, C. I. Torrie, D. T"oyr"a, F. Travasso, G. Traylor, J. Trinastic, M. C. Tringali, L. Trozzo, K. W. Tsang, M. Tse, R. Tso, L. Tsukada, D. Tsuna, D. Tuyenbayev, K. Ueno, D. Ugolini, C. S. Unnikrishnan, A. L. Urban, S. A. Usman, H. Vahlbruch, G. Vajente, G. Valdes, N. van Bakel, M. van Beuzekom, J. F. J. van den Brand, C. Van Den Broeck, D. C. Vander-Hyde, L. van der Schaaf, J. V. van Heijningen, A. A. van Veggel, M. Vardaro, V. Varma, S. Vass, M. Vas'uth, A. Vecchio, G. Vedovato, J. Veitch, P. J. Veitch, K. Venkateswara, G. Venugopalan, D. Verkindt, F. Vetrano, A. Vicer'e, A. D. Viets, S. Vinciguerra, D. J. Vine, J.-Y. Vinet, S. Vitale, T. Vo, H. Vocca, C. Vorvick, S. P. Vyatchanin, A. R. Wade, L. E. Wade, M. Wade, R. Walet, M. Walker, L. Wallace, S. Walsh, G. Wang, H. Wang, J. Z. Wang, W. H. Wang, Y. F. Wang, R. L. Ward, J. Warner, M. Was, J. Watchi, B. Weaver, L.-W. Wei, M. Weinert, A. J. Weinstein, R. Weiss, L. Wen, E. K. Wessel, P. Wessels, J. Westerweck, T. Westphal, K. Wette, J. T. Whelan, B. F. Whiting, C. Whittle, D. Wilken, D. Williams, R. D. Williams, A. R. Williamson, J. L. Willis, B. Willke, M. H. Wimmer, W. Winkler, C. C. Wipf, H. Wittel, G. Woan, J. Woehler, J. Wofford, K. W. K. Wong, J. Worden, J. L. Wright, D. S. Wu, D. M. Wysocki, S. Xiao, H. Yamamoto, C. C. Yancey, L. Yang, M. J. Yap, M. Yazback, Hang Yu, Haocun Yu, M. Yvert, A. Zadro.zny, M. Zanolin, T. Zelenova, J.-P. Zendri, M. Zevin, L. Zhang, M. Zhang, T. Zhang, Y.-H. Zhang, C. Zhao, M. Zhou, Z. Zhou, S. J. Zhu, X. J. Zhu, M. E. Zucker, J. Zweizig
First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data
9 Figures, 7 tables, submitted to PRD
Phys. Rev. D 96, 122006 (2017)
10.1103/PhysRevD.96.122006
null
gr-qc astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, {\it narrow-band} analyses methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of eleven pulsars using data from Advanced LIGO's first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched: in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far.
[ { "created": "Fri, 6 Oct 2017 09:48:46 GMT", "version": "v1" }, { "created": "Tue, 5 Dec 2017 15:50:57 GMT", "version": "v2" } ]
2018-01-03
[ [ "The LIGO Scientific Collaboration", "", "" ], [ "the Virgo Collaboration", "", "" ], [ "Abbott", "B. P.", "" ], [ "Abbott", "R.", "" ], [ "Abbott", "T. D.", "" ], [ "Acernese", "F.", "" ], [ "Ackley", "K.", "" ], [ "Adams", "C.", "" ], [ "Adams", "T.", "" ], [ "Addesso", "P.", "" ], [ "Adhikari", "R. X.", "" ], [ "Adya", "V. B.", "" ], [ "Affeldt", "C.", "" ], [ "Afrough", "M.", "" ], [ "Agarwal", "B.", "" ], [ "Agathos", "M.", "" ], [ "Agatsuma", "K.", "" ], [ "Aggarwal", "N.", "" ], [ "Aguiar", "O. D.", "" ], [ "Aiello", "L.", "" ], [ "Ain", "A.", "" ], [ "Allen", "B.", "" ], [ "Allen", "G.", "" ], [ "Allocca", "A.", "" ], [ "Altin", "P. A.", "" ], [ "Amato", "A.", "" ], [ "Ananyeva", "A.", "" ], [ "Anderson", "S. B.", "" ], [ "Anderson", "W. G.", "" ], [ "Angelova", "S. V.", "" ], [ "Antier", "S.", "" ], [ "Appert", "S.", "" ], [ "Arai", "K.", "" ], [ "Araya", "M. C.", "" ], [ "Areeda", "J. S.", "" ], [ "Arnaud", "N.", "" ], [ "Arun", "K. G.", "" ], [ "Ascenzi", "S.", "" ], [ "Ashton", "G.", "" ], [ "Ast", "M.", "" ], [ "Aston", "S. M.", "" ], [ "Astone", "P.", "" ], [ "Atallah", "D. V.", "" ], [ "Aufmuth", "P.", "" ], [ "Aulbert", "C.", "" ], [ "AultONeal", "K.", "" ], [ "Austin", "C.", "" ], [ "Avila-Alvarez", "A.", "" ], [ "Babak", "S.", "" ], [ "Bacon", "P.", "" ], [ "Bader", "M. K. M.", "" ], [ "Bae", "S.", "" ], [ "Baker", "P. T.", "" ], [ "Baldaccini", "F.", "" ], [ "Ballardin", "G.", "" ], [ "Ballmer", "S. W.", "" ], [ "Banagiri", "S.", "" ], [ "Barayoga", "J. C.", "" ], [ "Barclay", "S. E.", "" ], [ "Barish", "B. C.", "" ], [ "Barker", "D.", "" ], [ "Barkett", "K.", "" ], [ "Barone", "F.", "" ], [ "Barr", "B.", "" ], [ "Barsotti", "L.", "" ], [ "Barsuglia", "M.", "" ], [ "Barta", "D.", "" ], [ "Bartlett", "J.", "" ], [ "Bartos", "I.", "" ], [ "Bassiri", "R.", "" ], [ "Basti", "A.", "" ], [ "Batch", "J. C.", "" ], [ "Bawaj", "M.", "" ], [ "Bayley", "J. C.", "" ], [ "Bazzan", "M.", "" ], [ "Bécsy", "B.", "" ], [ "Beer", "C.", "" ], [ "Bejger", "M.", "" ], [ "Belahcene", "I.", "" ], [ "Bell", "A. S.", "" ], [ "Berger", "B. K.", "" ], [ "Bergmann", "G.", "" ], [ "Bero", "J. J.", "" ], [ "Berry", "C. P. L.", "" ], [ "Bersanetti", "D.", "" ], [ "Bertolini", "A.", "" ], [ "Betzwieser", "J.", "" ], [ "Bhagwat", "S.", "" ], [ "Bhandare", "R.", "" ], [ "Bilenko", "I. A.", "" ], [ "Billingsley", "G.", "" ], [ "Billman", "C. R.", "" ], [ "Birch", "J.", "" ], [ "Birney", "R.", "" ], [ "Birnholtz", "O.", "" ], [ "Biscans", "S.", "" ], [ "Biscoveanu", "S.", "" ], [ "Bisht", "A.", "" ], [ "Bitossi", "M.", "" ], [ "Biwer", "C.", "" ], [ "Bizouard", "M. A.", "" ], [ "Blackburn", "J. K.", "" ], [ "Blackman", "J.", "" ], [ "Blair", "C. D.", "" ], [ "Blair", "D. G.", "" ], [ "Blair", "R. M.", "" ], [ "Bloemen", "S.", "" ], [ "Bock", "O.", "" ], [ "Bode", "N.", "" ], [ "Boer", "M.", "" ], [ "Bogaert", "G.", "" ], [ "Bohe", "A.", "" ], [ "Bondu", "F.", "" ], [ "Bonilla", "E.", "" ], [ "Bonnand", "R.", "" ], [ "Boom", "B. A.", "" ], [ "Bork", "R.", "" ], [ "Boschi", "V.", "" ], [ "Bose", "S.", "" ], [ "Bossie", "K.", "" ], [ "Bouffanais", "Y.", "" ], [ "Bozzi", "A.", "" ], [ "Bradaschia", "C.", "" ], [ "Brady", "P. R.", "" ], [ "Branchesi", "M.", "" ], [ "Brau", "J. E.", "" ], [ "Briant", "T.", "" ], [ "Brillet", "A.", "" ], [ "Brinkmann", "M.", "" ], [ "Brisson", "V.", "" ], [ "Brockill", "P.", "" ], [ "Broida", "J. E.", "" ], [ "Brooks", "A. F.", "" ], [ "Brown", "D. A.", "" ], [ "Brown", "D. D.", "" ], [ "Brunett", "S.", "" ], [ "Buchanan", "C. C.", "" ], [ "Buikema", "A.", "" ], [ "Bulik", "T.", "" ], [ "Bulten", "H. J.", "" ], [ "Buonanno", "A.", "" ], [ "Buskulic", "D.", "" ], [ "Buy", "C.", "" ], [ "Byer", "R. L.", "" ], [ "Cabero", "M.", "" ], [ "Cadonati", "L.", "" ], [ "Cagnoli", "G.", "" ], [ "Cahillane", "C.", "" ], [ "Bustillo", "J. Calder'on", "" ], [ "Callister", "T. A.", "" ], [ "Calloni", "E.", "" ], [ "Camp", "J. B.", "" ], [ "Canizares", "P.", "" ], [ "Cannon", "K. C.", "" ], [ "Cao", "H.", "" ], [ "Cao", "J.", "" ], [ "Capano", "C. D.", "" ], [ "Capocasa", "E.", "" ], [ "Carbognani", "F.", "" ], [ "Caride", "S.", "" ], [ "Carney", "M. F.", "" ], [ "Diaz", "J. Casanueva", "" ], [ "Casentini", "C.", "" ], [ "Caudill", "S.", "" ], [ "Cavaglià", "M.", "" ], [ "Cavalier", "F.", "" ], [ "Cavalieri", "R.", "" ], [ "Cella", "G.", "" ], [ "Cepeda", "C. B.", "" ], [ "Cerd'a-Dur'an", "P.", "" ], [ "Cerretani", "G.", "" ], [ "Cesarini", "E.", "" ], [ "Chamberlin", "S. J.", "" ], [ "Chan", "M.", "" ], [ "Chao", "S.", "" ], [ "Charlton", "P.", "" ], [ "Chase", "E.", "" ], [ "Chassande-Mottin", "E.", "" ], [ "Chatterjee", "D.", "" ], [ "Cheeseboro", "B. D.", "" ], [ "Chen", "H. Y.", "" ], [ "Chen", "X.", "" ], [ "Chen", "Y.", "" ], [ "Cheng", "H. -P.", "" ], [ "Chia", "H.", "" ], [ "Chincarini", "A.", "" ], [ "Chiummo", "A.", "" ], [ "Chmiel", "T.", "" ], [ "Cho", "H. S.", "" ], [ "Cho", "M.", "" ], [ "Chow", "J. H.", "" ], [ "Christensen", "N.", "" ], [ "Chu", "Q.", "" ], [ "Chua", "A. J. K.", "" ], [ "Chua", "S.", "" ], [ "Chung", "A. K. W.", "" ], [ "Chung", "S.", "" ], [ "Ciani", "G.", "" ], [ "Ciolfi", "R.", "" ], [ "Cirelli", "C. E.", "" ], [ "Cirone", "A.", "" ], [ "Clara", "F.", "" ], [ "Clark", "J. A.", "" ], [ "Clearwater", "P.", "" ], [ "Cleva", "F.", "" ], [ "Cocchieri", "C.", "" ], [ "Coccia", "E.", "" ], [ "Cohadon", "P. -F.", "" ], [ "Cohen", "D.", "" ], [ "Colla", "A.", "" ], [ "Collette", "C. G.", "" ], [ "Cominsky", "L. R.", "" ], [ "Constancio", "M.", "Jr." ], [ "Conti", "L.", "" ], [ "Cooper", "S. J.", "" ], [ "Corban", "P.", "" ], [ "Corbitt", "T. R.", "" ], [ "Cordero-Carri'on", "I.", "" ], [ "Corley", "K. R.", "" ], [ "Cornish", "N.", "" ], [ "Corsi", "A.", "" ], [ "Cortese", "S.", "" ], [ "Costa", "C. A.", "" ], [ "Coughlin", "M. W.", "" ], [ "Coughlin", "S. B.", "" ], [ "Coulon", "J. -P.", "" ], [ "Countryman", "S. T.", "" ], [ "Couvares", "P.", "" ], [ "Covas", "P. B.", "" ], [ "Cowan", "E. E.", "" ], [ "Coward", "D. M.", "" ], [ "Cowart", "M. J.", "" ], [ "Coyne", "D. C.", "" ], [ "Coyne", "R.", "" ], [ "Creighton", "J. D. E.", "" ], [ "Creighton", "T. D.", "" ], [ "Cripe", "J.", "" ], [ "Crowder", "S. G.", "" ], [ "Cullen", "T. J.", "" ], [ "Cumming", "A.", "" ], [ "Cunningham", "L.", "" ], [ "Cuoco", "E.", "" ], [ "Canton", "T. Dal", "" ], [ "D'alya", "G.", "" ], [ "Danilishin", "S. L.", "" ], [ "D'Antonio", "S.", "" ], [ "Danzmann", "K.", "" ], [ "Dasgupta", "A.", "" ], [ "Costa", "C. F. Da Silva", "" ], [ "Dattilo", "V.", "" ], [ "Dave", "I.", "" ], [ "Davier", "M.", "" ], [ "Davis", "D.", "" ], [ "Daw", "E. J.", "" ], [ "Day", "B.", "" ], [ "De", "S.", "" ], [ "DeBra", "D.", "" ], [ "Degallaix", "J.", "" ], [ "De Laurentis", "M.", "" ], [ "Del'eglise", "S.", "" ], [ "Del Pozzo", "W.", "" ], [ "Demos", "N.", "" ], [ "Denker", "T.", "" ], [ "Dent", "T.", "" ], [ "De Pietri", "R.", "" ], [ "Dergachev", "V.", "" ], [ "De Rosa", "R.", "" ], [ "DeRosa", "R. T.", "" ], [ "De Rossi", "C.", "" ], [ "DeSalvo", "R.", "" ], [ "de Varona", "O.", "" ], [ "Devenson", "J.", "" ], [ "Dhurandhar", "S.", "" ], [ "D'iaz", "M. C.", "" ], [ "Di Fiore", "L.", "" ], [ "Di Giovanni", "M.", "" ], [ "Di Girolamo", "T.", "" ], [ "Di Lieto", "A.", "" ], [ "Di Pace", "S.", "" ], [ "Di Palma", "I.", "" ], [ "Di Renzo", "F.", "" ], [ "Doctor", "Z.", "" ], [ "Dolique", "V.", "" ], [ "Donovan", "F.", "" ], [ "Dooley", "K. L.", "" ], [ "Doravari", "S.", "" ], [ "Dorrington", "I.", "" ], [ "Douglas", "R.", "" ], [ "'Alvarez", "M. Dovale", "" ], [ "Downes", "T. P.", "" ], [ "Drago", "M.", "" ], [ "Dreissigacker", "C.", "" ], [ "Driggers", "J. C.", "" ], [ "Du", "Z.", "" ], [ "Ducrot", "M.", "" ], [ "Dupej", "P.", "" ], [ "Dwyer", "S. E.", "" ], [ "Edo", "T. B.", "" ], [ "Edwards", "M. C.", "" ], [ "Effler", "A.", "" ], [ "Eggenstein", "H. -B.", "" ], [ "Ehrens", "P.", "" ], [ "Eichholz", "J.", "" ], [ "Eikenberry", "S. S.", "" ], [ "Eisenstein", "R. A.", "" ], [ "Essick", "R. C.", "" ], [ "Estevez", "D.", "" ], [ "Etienne", "Z. B.", "" ], [ "Etzel", "T.", "" ], [ "Evans", "M.", "" ], [ "Evans", "T. M.", "" ], [ "Factourovich", "M.", "" ], [ "Fafone", "V.", "" ], [ "Fair", "H.", "" ], [ "Fairhurst", "S.", "" ], [ "Fan", "X.", "" ], [ "Farinon", "S.", "" ], [ "Farr", "B.", "" ], [ "Farr", "W. M.", "" ], [ "Fauchon-Jones", "E. J.", "" ], [ "Favata", "M.", "" ], [ "Fays", "M.", "" ], [ "Fee", "C.", "" ], [ "Fehrmann", "H.", "" ], [ "Feicht", "J.", "" ], [ "Fejer", "M. M.", "" ], [ "Fernandez-Galiana", "A.", "" ], [ "Ferrante", "I.", "" ], [ "Ferreira", "E. C.", "" ], [ "Ferrini", "F.", "" ], [ "Fidecaro", "F.", "" ], [ "Finstad", "D.", "" ], [ "Fiori", "I.", "" ], [ "Fiorucci", "D.", "" ], [ "Fishbach", "M.", "" ], [ "Fisher", "R. P.", "" ], [ "Fitz-Axen", "M.", "" ], [ "Flaminio", "R.", "" ], [ "Fletcher", "M.", "" ], [ "Fong", "H.", "" ], [ "Font", "J. A.", "" ], [ "Forsyth", "P. W. F.", "" ], [ "Forsyth", "S. S.", "" ], [ "Fournier", "J. -D.", "" ], [ "Frasca", "S.", "" ], [ "Frasconi", "F.", "" ], [ "Frei", "Z.", "" ], [ "Freise", "A.", "" ], [ "Frey", "R.", "" ], [ "Frey", "V.", "" ], [ "Fries", "E. M.", "" ], [ "Fritschel", "P.", "" ], [ "Frolov", "V. V.", "" ], [ "Fulda", "P.", "" ], [ "Fyffe", "M.", "" ], [ "Gabbard", "H.", "" ], [ "Gadre", "B. U.", "" ], [ "Gaebel", "S. M.", "" ], [ "Gair", "J. R.", "" ], [ "Gammaitoni", "L.", "" ], [ "Ganija", "M. R.", "" ], [ "Gaonkar", "S. G.", "" ], [ "Garcia-Quiros", "C.", "" ], [ "Garufi", "F.", "" ], [ "Gateley", "B.", "" ], [ "Gaudio", "S.", "" ], [ "Gaur", "G.", "" ], [ "Gayathri", "V.", "" ], [ "Gehrels", "N.", "" ], [ "Gemme", "G.", "" ], [ "Genin", "E.", "" ], [ "Gennai", "A.", "" ], [ "George", "D.", "" ], [ "George", "J.", "" ], [ "Gergely", "L.", "" ], [ "Germain", "V.", "" ], [ "Ghonge", "S.", "" ], [ "Ghosh", "Abhirup", "" ], [ "Ghosh", "Archisman", "" ], [ "Ghosh", "S.", "" ], [ "Giaime", "J. A.", "" ], [ "Giardina", "K. D.", "" ], [ "Giazotto", "A.", "" ], [ "Gill", "K.", "" ], [ "Glover", "L.", "" ], [ "Goetz", "E.", "" ], [ "Goetz", "R.", "" ], [ "Gomes", "S.", "" ], [ "Goncharov", "B.", "" ], [ "Gonz'alez", "G.", "" ], [ "Castro", "J. M. Gonzalez", "" ], [ "Gopakumar", "A.", "" ], [ "Gorodetsky", "M. L.", "" ], [ "Gossan", "S. E.", "" ], [ "Gosselin", "M.", "" ], [ "Gouaty", "R.", "" ], [ "Grado", "A.", "" ], [ "Graef", "C.", "" ], [ "Granata", "M.", "" ], [ "Grant", "A.", "" ], [ "Gras", "S.", "" ], [ "Gray", "C.", "" ], [ "Greco", "G.", "" ], [ "Green", "A. C.", "" ], [ "Gretarsson", "E. M.", "" ], [ "Groot", "P.", "" ], [ "Grote", "H.", "" ], [ "Grunewald", "S.", "" ], [ "Gruning", "P.", "" ], [ "Guidi", "G. M.", "" ], [ "Guo", "X.", "" ], [ "Gupta", "A.", "" ], [ "Gupta", "M. K.", "" ], [ "Gushwa", "K. E.", "" ], [ "Gustafson", "E. K.", "" ], [ "Gustafson", "R.", "" ], [ "Halim", "O.", "" ], [ "Hall", "B. R.", "" ], [ "Hall", "E. D.", "" ], [ "Hamilton", "E. Z.", "" ], [ "Hammond", "G.", "" ], [ "Haney", "M.", "" ], [ "Hanke", "M. M.", "" ], [ "Hanks", "J.", "" ], [ "Hanna", "C.", "" ], [ "Hannam", "M. D.", "" ], [ "Hannuksela", "O. A.", "" ], [ "Hanson", "J.", "" ], [ "Hardwick", "T.", "" ], [ "Harms", "J.", "" ], [ "Harry", "G. M.", "" ], [ "Harry", "I. W.", "" ], [ "Hart", "M. J.", "" ], [ "Haster", "C. -J.", "" ], [ "Haughian", "K.", "" ], [ "Healy", "J.", "" ], [ "Heidmann", "A.", "" ], [ "Heintze", "M. C.", "" ], [ "Heitmann", "H.", "" ], [ "Hello", "P.", "" ], [ "Hemming", "G.", "" ], [ "Hendry", "M.", "" ], [ "Heng", "I. S.", "" ], [ "Hennig", "J.", "" ], [ "Heptonstall", "A. W.", "" ], [ "Heurs", "M.", "" ], [ "Hild", "S.", "" ], [ "Hinderer", "T.", "" ], [ "Ho", "W. C. G.", "" ], [ "Hoak", "D.", "" ], [ "Hofman", "D.", "" ], [ "Holt", "K.", "" ], [ "Holz", "D. E.", "" ], [ "Hopkins", "P.", "" ], [ "Horst", "C.", "" ], [ "Hough", "J.", "" ], [ "Houston", "E. A.", "" ], [ "Howell", "E. J.", "" ], [ "Hreibi", "A.", "" ], [ "Hu", "Y. M.", "" ], [ "Huerta", "E. A.", "" ], [ "Huet", "D.", "" ], [ "Hughey", "B.", "" ], [ "Husa", "S.", "" ], [ "Huttner", "S. H.", "" ], [ "Huynh-Dinh", "T.", "" ], [ "Indik", "N.", "" ], [ "Inta", "R.", "" ], [ "Intini", "G.", "" ], [ "Isa", "H. N.", "" ], [ "Isac", "J. -M.", "" ], [ "Isi", "M.", "" ], [ "Iyer", "B. R.", "" ], [ "Izumi", "K.", "" ], [ "Jacqmin", "T.", "" ], [ "Jani", "K.", "" ], [ "Jaranowski", "P.", "" ], [ "Jawahar", "S.", "" ], [ "Jim'enez-Forteza", "F.", "" ], [ "Johnson", "W. W.", "" ], [ "Jones", "D. I.", "" ], [ "Jones", "R.", "" ], [ "Jonker", "R. J. G.", "" ], [ "Ju", "L.", "" ], [ "Junker", "J.", "" ], [ "Kalaghatgi", "C. V.", "" ], [ "Kalogera", "V.", "" ], [ "Kamai", "B.", "" ], [ "Kandhasamy", "S.", "" ], [ "Kang", "G.", "" ], [ "Kanner", "J. B.", "" ], [ "Kapadia", "S. J.", "" ], [ "Karki", "S.", "" ], [ "Karvinen", "K. S.", "" ], [ "Kasprzack", "M.", "" ], [ "Katolik", "M.", "" ], [ "Katsavounidis", "E.", "" ], [ "Katzman", "W.", "" ], [ "Kaufer", "S.", "" ], [ "Kawabe", "K.", "" ], [ "K'ef'elian", "F.", "" ], [ "Keitel", "D.", "" ], [ "Kemball", "A. J.", "" ], [ "Kennedy", "R.", "" ], [ "Kent", "C.", "" ], [ "Key", "J. S.", "" ], [ "Khalili", "F. Y.", "" ], [ "Khan", "I.", "" ], [ "Khan", "S.", "" ], [ "Khan", "Z.", "" ], [ "Khazanov", "E. A.", "" ], [ "Kijbunchoo", "N.", "" ], [ "Kim", "Chunglee", "" ], [ "Kim", "J. C.", "" ], [ "Kim", "K.", "" ], [ "Kim", "W.", "" ], [ "Kim", "W. S.", "" ], [ "Kim", "Y. -M.", "" ], [ "Kimbrell", "S. J.", "" ], [ "King", "E. J.", "" ], [ "King", "P. J.", "" ], [ "Kinley-Hanlon", "M.", "" ], [ "Kirchhoff", "R.", "" ], [ "Kissel", "J. S.", "" ], [ "Kleybolte", "L.", "" ], [ "Klimenko", "S.", "" ], [ "Knowles", "T. D.", "" ], [ "Koch", "P.", "" ], [ "Koehlenbeck", "S. M.", "" ], [ "Koley", "S.", "" ], [ "Kondrashov", "V.", "" ], [ "Kontos", "A.", "" ], [ "Korobko", "M.", "" ], [ "Korth", "W. Z.", "" ], [ "Kowalska", "I.", "" ], [ "Kozak", "D. B.", "" ], [ "Kr\"amer", "C.", "" ], [ "Kringel", "V.", "" ], [ "Krishnan", "B.", "" ], [ "Kr'olak", "A.", "" ], [ "Kuehn", "G.", "" ], [ "Kumar", "P.", "" ], [ "Kumar", "R.", "" ], [ "Kumar", "S.", "" ], [ "Kuo", "L.", "" ], [ "Kutynia", "A.", "" ], [ "Kwang", "S.", "" ], [ "Lackey", "B. D.", "" ], [ "Lai", "K. H.", "" ], [ "Landry", "M.", "" ], [ "Lang", "R. N.", "" ], [ "Lange", "J.", "" ], [ "Lantz", "B.", "" ], [ "Lanza", "R. K.", "" ], [ "Lartaux-Vollard", "A.", "" ], [ "Lasky", "P. D.", "" ], [ "Laxen", "M.", "" ], [ "Lazzarini", "A.", "" ], [ "Lazzaro", "C.", "" ], [ "Leaci", "P.", "" ], [ "Leavey", "S.", "" ], [ "Lee", "C. H.", "" ], [ "Lee", "H. K.", "" ], [ "Lee", "H. M.", "" ], [ "Lee", "H. W.", "" ], [ "Lee", "K.", "" ], [ "Lehmann", "J.", "" ], [ "Lenon", "A.", "" ], [ "Leonardi", "M.", "" ], [ "Leroy", "N.", "" ], [ "Letendre", "N.", "" ], [ "Levin", "Y.", "" ], [ "Li", "T. G. F.", "" ], [ "Linker", "S. D.", "" ], [ "Littenberg", "T. B.", "" ], [ "Liu", "J.", "" ], [ "Lo", "R. K. L.", "" ], [ "Lockerbie", "N. A.", "" ], [ "London", "L. T.", "" ], [ "Lord", "J. E.", "" ], [ "Lorenzini", "M.", "" ], [ "Loriette", "V.", "" ], [ "Lormand", "M.", "" ], [ "Losurdo", "G.", "" ], [ "Lough", "J. D.", "" ], [ "Lovelace", "G.", "" ], [ "Lück", "H.", "" ], [ "Lumaca", "D.", "" ], [ "Lundgren", "A. P.", "" ], [ "Lynch", "R.", "" ], [ "Ma", "Y.", "" ], [ "Macas", "R.", "" ], [ "Macfoy", "S.", "" ], [ "Machenschalk", "B.", "" ], [ "MacInnis", "M.", "" ], [ "Macleod", "D. M.", "" ], [ "Hernandez", "I. Magaña", "" ], [ "Magaña-Sandoval", "F.", "" ], [ "Zertuche", "L. Magaña", "" ], [ "Magee", "R. M.", "" ], [ "Majorana", "E.", "" ], [ "Maksimovic", "I.", "" ], [ "Man", "N.", "" ], [ "Mandic", "V.", "" ], [ "Mangano", "V.", "" ], [ "Mansell", "G. L.", "" ], [ "Manske", "M.", "" ], [ "Mantovani", "M.", "" ], [ "Marchesoni", "F.", "" ], [ "Marion", "F.", "" ], [ "M'arka", "S.", "" ], [ "M'arka", "Z.", "" ], [ "Markakis", "C.", "" ], [ "Markosyan", "A. S.", "" ], [ "Markowitz", "A.", "" ], [ "Maros", "E.", "" ], [ "Marquina", "A.", "" ], [ "Martelli", "F.", "" ], [ "Martellini", "L.", "" ], [ "Martin", "I. W.", "" ], [ "Martin", "R. M.", "" ], [ "Martynov", "D. V.", "" ], [ "Mason", "K.", "" ], [ "Massera", "E.", "" ], [ "Masserot", "A.", "" ], [ "Massinger", "T. J.", "" ], [ "Masso-Reid", "M.", "" ], [ "Mastrogiovanni", "S.", "" ], [ "Matas", "A.", "" ], [ "Matichard", "F.", "" ], [ "Matone", "L.", "" ], [ "Mavalvala", "N.", "" ], [ "Mazumder", "N.", "" ], [ "McCarthy", "R.", "" ], [ "McClelland", "D. E.", "" ], [ "McCormick", "S.", "" ], [ "McCuller", "L.", "" ], [ "McGuire", "S. C.", "" ], [ "McIntyre", "G.", "" ], [ "McIver", "J.", "" ], [ "McManus", "D. J.", "" ], [ "McNeill", "L.", "" ], [ "McRae", "T.", "" ], [ "McWilliams", "S. T.", "" ], [ "Meacher", "D.", "" ], [ "Meadors", "G. D.", "" ], [ "Mehmet", "M.", "" ], [ "Meidam", "J.", "" ], [ "Mejuto-Villa", "E.", "" ], [ "Melatos", "A.", "" ], [ "Mendell", "G.", "" ], [ "Mercer", "R. A.", "" ], [ "Merilh", "E. L.", "" ], [ "Merzougui", "M.", "" ], [ "Meshkov", "S.", "" ], [ "Messenger", "C.", "" ], [ "Messick", "C.", "" ], [ "Metzdorff", "R.", "" ], [ "Meyers", "P. M.", "" ], [ "Miao", "H.", "" ], [ "Michel", "C.", "" ], [ "Middleton", "H.", "" ], [ "Mikhailov", "E. E.", "" ], [ "Milano", "L.", "" ], [ "Miller", "A. L.", "" ], [ "Miller", "B. B.", "" ], [ "Miller", "J.", "" ], [ "Millhouse", "M.", "" ], [ "Milovich-Goff", "M. C.", "" ], [ "Minazzoli", "O.", "" ], [ "Minenkov", "Y.", "" ], [ "Ming", "J.", "" ], [ "Mishra", "C.", "" ], [ "Mitra", "S.", "" ], [ "Mitrofanov", "V. P.", "" ], [ "Mitselmakher", "G.", "" ], [ "Mittleman", "R.", "" ], [ "Moffa", "D.", "" ], [ "Moggi", "A.", "" ], [ "Mogushi", "K.", "" ], [ "Mohan", "M.", "" ], [ "Mohapatra", "S. R. P.", "" ], [ "Montani", "M.", "" ], [ "Moore", "C. J.", "" ], [ "Moraru", "D.", "" ], [ "Moreno", "G.", "" ], [ "Morriss", "S. R.", "" ], [ "Mours", "B.", "" ], [ "Mow-Lowry", "C. M.", "" ], [ "Mueller", "G.", "" ], [ "Muir", "A. W.", "" ], [ "Mukherjee", "Arunava", "" ], [ "Mukherjee", "D.", "" ], [ "Mukherjee", "S.", "" ], [ "Mukund", "N.", "" ], [ "Mullavey", "A.", "" ], [ "Munch", "J.", "" ], [ "Muñiz", "E. A.", "" ], [ "Muratore", "M.", "" ], [ "Murray", "P. G.", "" ], [ "Napier", "K.", "" ], [ "Nardecchia", "I.", "" ], [ "Naticchioni", "L.", "" ], [ "Nayak", "R. K.", "" ], [ "Neilson", "J.", "" ], [ "Nelemans", "G.", "" ], [ "Nelson", "T. J. N.", "" ], [ "Nery", "M.", "" ], [ "Neunzert", "A.", "" ], [ "Nevin", "L.", "" ], [ "Newport", "J. M.", "" ], [ "Newton", "G.", "" ], [ "Ng", "K. K. Y.", "" ], [ "Nguyen", "T. T.", "" ], [ "Nichols", "D.", "" ], [ "Nielsen", "A. B.", "" ], [ "Nissanke", "S.", "" ], [ "Nitz", "A.", "" ], [ "Noack", "A.", "" ], [ "Nocera", "F.", "" ], [ "Nolting", "D.", "" ], [ "North", "C.", "" ], [ "Nuttall", "L. K.", "" ], [ "Oberling", "J.", "" ], [ "O'Dea", "G. D.", "" ], [ "Ogin", "G. H.", "" ], [ "Oh", "J. J.", "" ], [ "Oh", "S. H.", "" ], [ "Ohme", "F.", "" ], [ "Okada", "M. A.", "" ], [ "Oliver", "M.", "" ], [ "Oppermann", "P.", "" ], [ "Oram", "Richard J.", "" ], [ "O'Reilly", "B.", "" ], [ "Ormiston", "R.", "" ], [ "Ortega", "L. F.", "" ], [ "O'Shaughnessy", "R.", "" ], [ "Ossokine", "S.", "" ], [ "Ottaway", "D. J.", "" ], [ "Overmier", "H.", "" ], [ "Owen", "B. J.", "" ], [ "Pace", "A. E.", "" ], [ "Page", "J.", "" ], [ "Page", "M. A.", "" ], [ "Pai", "A.", "" ], [ "Pai", "S. A.", "" ], [ "Palamos", "J. R.", "" ], [ "Palashov", "O.", "" ], [ "Palomba", "C.", "" ], [ "Pal-Singh", "A.", "" ], [ "Pan", "Howard", "" ], [ "Pan", "Huang-Wei", "" ], [ "Pang", "B.", "" ], [ "Pang", "P. T. H.", "" ], [ "Pankow", "C.", "" ], [ "Pannarale", "F.", "" ], [ "Pant", "B. C.", "" ], [ "Paoletti", "F.", "" ], [ "Paoli", "A.", "" ], [ "Papa", "M. A.", "" ], [ "Parida", "A.", "" ], [ "Parker", "W.", "" ], [ "Pascucci", "D.", "" ], [ "Pasqualetti", "A.", "" ], [ "Passaquieti", "R.", "" ], [ "Passuello", "D.", "" ], [ "Patil", "M.", "" ], [ "Patricelli", "B.", "" ], [ "Pearlstone", "B. L.", "" ], [ "Pedraza", "M.", "" ], [ "Pedurand", "R.", "" ], [ "Pekowsky", "L.", "" ], [ "Pele", "A.", "" ], [ "Penn", "S.", "" ], [ "Perez", "C. J.", "" ], [ "Perreca", "A.", "" ], [ "Perri", "L. M.", "" ], [ "Pfeiffer", "H. P.", "" ], [ "Phelps", "M.", "" ], [ "Piccinni", "O. J.", "" ], [ "Pichot", "M.", "" ], [ "Piergiovanni", "F.", "" ], [ "Pierro", "V.", "" ], [ "Pillant", "G.", "" ], [ "Pinard", "L.", "" ], [ "Pinto", "I. M.", "" ], [ "Pirello", "M.", "" ], [ "Pitkin", "M.", "" ], [ "Poe", "M.", "" ], [ "Poggiani", "R.", "" ], [ "Popolizio", "P.", "" ], [ "Porter", "E. K.", "" ], [ "Post", "A.", "" ], [ "Powell", "J.", "" ], [ "Prasad", "J.", "" ], [ "Pratt", "J. W. W.", "" ], [ "Pratten", "G.", "" ], [ "Predoi", "V.", "" ], [ "Prestegard", "T.", "" ], [ "Prijatelj", "M.", "" ], [ "Principe", "M.", "" ], [ "Privitera", "S.", "" ], [ "Prodi", "G. A.", "" ], [ "Prokhorov", "L. G.", "" ], [ "Puncken", "O.", "" ], [ "Punturo", "M.", "" ], [ "Puppo", "P.", "" ], [ "P\"urrer", "M.", "" ], [ "Qi", "H.", "" ], [ "Quetschke", "V.", "" ], [ "Quintero", "E. A.", "" ], [ "Quitzow-James", "R.", "" ], [ "Raab", "F. J.", "" ], [ "Rabeling", "D. S.", "" ], [ "Radkins", "H.", "" ], [ "Raffai", "P.", "" ], [ "Raja", "S.", "" ], [ "Rajan", "C.", "" ], [ "Rajbhandari", "B.", "" ], [ "Rakhmanov", "M.", "" ], [ "Ramirez", "K. E.", "" ], [ "Ramos-Buades", "A.", "" ], [ "Rapagnani", "P.", "" ], [ "Raymond", "V.", "" ], [ "Razzano", "M.", "" ], [ "Read", "J.", "" ], [ "Regimbau", "T.", "" ], [ "Rei", "L.", "" ], [ "Reid", "S.", "" ], [ "Reitze", "D. H.", "" ], [ "Ren", "W.", "" ], [ "Reyes", "S. D.", "" ], [ "Ricci", "F.", "" ], [ "Ricker", "P. M.", "" ], [ "Rieger", "S.", "" ], [ "Riles", "K.", "" ], [ "Rizzo", "M.", "" ], [ "Robertson", "N. A.", "" ], [ "Robie", "R.", "" ], [ "Robinet", "F.", "" ], [ "Rocchi", "A.", "" ], [ "Rolland", "L.", "" ], [ "Rollins", "J. G.", "" ], [ "Roma", "V. J.", "" ], [ "Romano", "R.", "" ], [ "Romel", "C. L.", "" ], [ "Romie", "J. H.", "" ], [ "Rosi'nska", "D.", "" ], [ "Ross", "M. P.", "" ], [ "Rowan", "S.", "" ], [ "R\"udiger", "A.", "" ], [ "Ruggi", "P.", "" ], [ "Rutins", "G.", "" ], [ "Ryan", "K.", "" ], [ "Sachdev", "S.", "" ], [ "Sadecki", "T.", "" ], [ "Sadeghian", "L.", "" ], [ "Sakellariadou", "M.", "" ], [ "Salconi", "L.", "" ], [ "Saleem", "M.", "" ], [ "Salemi", "F.", "" ], [ "Samajdar", "A.", "" ], [ "Sammut", "L.", "" ], [ "Sampson", "L. M.", "" ], [ "Sanchez", "E. J.", "" ], [ "Sanchez", "L. E.", "" ], [ "Sanchis-Gual", "N.", "" ], [ "Sandberg", "V.", "" ], [ "Sanders", "J. R.", "" ], [ "Sassolas", "B.", "" ], [ "Sathyaprakash", "B. S.", "" ], [ "Saulson", "P. R.", "" ], [ "Sauter", "O.", "" ], [ "Savage", "R. L.", "" ], [ "Sawadsky", "A.", "" ], [ "Schale", "P.", "" ], [ "Scheel", "M.", "" ], [ "Scheuer", "J.", "" ], [ "Schmidt", "J.", "" ], [ "Schmidt", "P.", "" ], [ "Schnabel", "R.", "" ], [ "Schofield", "R. M. S.", "" ], [ "Sch\"onbeck", "A.", "" ], [ "Schreiber", "E.", "" ], [ "Schuette", "D.", "" ], [ "Schulte", "B. W.", "" ], [ "Schutz", "B. F.", "" ], [ "Schwalbe", "S. G.", "" ], [ "Scott", "J.", "" ], [ "Scott", "S. M.", "" ], [ "Seidel", "E.", "" ], [ "Sellers", "D.", "" ], [ "Sengupta", "A. S.", "" ], [ "Sentenac", "D.", "" ], [ "Sequino", "V.", "" ], [ "Sergeev", "A.", "" ], [ "Shaddock", "D. A.", "" ], [ "Shaffer", "T. J.", "" ], [ "Shah", "A. A.", "" ], [ "Shahriar", "M. S.", "" ], [ "Shaner", "M. B.", "" ], [ "Shao", "L.", "" ], [ "Shapiro", "B.", "" ], [ "Shawhan", "P.", "" ], [ "Sheperd", "A.", "" ], [ "Shoemaker", "D. H.", "" ], [ "Shoemaker", "D. M.", "" ], [ "Siellez", "K.", "" ], [ "Siemens", "X.", "" ], [ "Sieniawska", "M.", "" ], [ "Sigg", "D.", "" ], [ "Silva", "A. D.", "" ], [ "Singer", "L. P.", "" ], [ "Singh", "A.", "" ], [ "Singhal", "A.", "" ], [ "Sintes", "A. M.", "" ], [ "Slagmolen", "B. J. J.", "" ], [ "Smith", "B.", "" ], [ "Smith", "J. R.", "" ], [ "Smith", "R. J. E.", "" ], [ "Somala", "S.", "" ], [ "Son", "E. J.", "" ], [ "Sonnenberg", "J. A.", "" ], [ "Sorazu", "B.", "" ], [ "Sorrentino", "F.", "" ], [ "Souradeep", "T.", "" ], [ "Spencer", "A. P.", "" ], [ "Srivastava", "A. K.", "" ], [ "Staats", "K.", "" ], [ "Staley", "A.", "" ], [ "Steinke", "M.", "" ], [ "Steinlechner", "J.", "" ], [ "Steinlechner", "S.", "" ], [ "Steinmeyer", "D.", "" ], [ "Stevenson", "S. P.", "" ], [ "Stone", "R.", "" ], [ "Stops", "D. J.", "" ], [ "Strain", "K. A.", "" ], [ "Stratta", "G.", "" ], [ "Strigin", "S. E.", "" ], [ "Strunk", "A.", "" ], [ "Sturani", "R.", "" ], [ "Stuver", "A. L.", "" ], [ "Summerscales", "T. Z.", "" ], [ "Sun", "L.", "" ], [ "Sunil", "S.", "" ], [ "Suresh", "J.", "" ], [ "Sutton", "P. J.", "" ], [ "Swinkels", "B. L.", "" ], [ "Szczepa'nczyk", "M. J.", "" ], [ "Tacca", "M.", "" ], [ "Tait", "S. C.", "" ], [ "Talbot", "C.", "" ], [ "Talukder", "D.", "" ], [ "Tanner", "D. B.", "" ], [ "T'apai", "M.", "" ], [ "Taracchini", "A.", "" ], [ "Tasson", "J. D.", "" ], [ "Taylor", "J. A.", "" ], [ "Taylor", "R.", "" ], [ "Tewari", "S. V.", "" ], [ "Theeg", "T.", "" ], [ "Thies", "F.", "" ], [ "Thomas", "E. G.", "" ], [ "Thomas", "M.", "" ], [ "Thomas", "P.", "" ], [ "Thorne", "K. A.", "" ], [ "Thrane", "E.", "" ], [ "Tiwari", "S.", "" ], [ "Tiwari", "V.", "" ], [ "Tokmakov", "K. V.", "" ], [ "Toland", "K.", "" ], [ "Tonelli", "M.", "" ], [ "Tornasi", "Z.", "" ], [ "Torres-Forn'e", "A.", "" ], [ "Torrie", "C. I.", "" ], [ "T\"oyr\"a", "D.", "" ], [ "Travasso", "F.", "" ], [ "Traylor", "G.", "" ], [ "Trinastic", "J.", "" ], [ "Tringali", "M. C.", "" ], [ "Trozzo", "L.", "" ], [ "Tsang", "K. W.", "" ], [ "Tse", "M.", "" ], [ "Tso", "R.", "" ], [ "Tsukada", "L.", "" ], [ "Tsuna", "D.", "" ], [ "Tuyenbayev", "D.", "" ], [ "Ueno", "K.", "" ], [ "Ugolini", "D.", "" ], [ "Unnikrishnan", "C. S.", "" ], [ "Urban", "A. L.", "" ], [ "Usman", "S. A.", "" ], [ "Vahlbruch", "H.", "" ], [ "Vajente", "G.", "" ], [ "Valdes", "G.", "" ], [ "van Bakel", "N.", "" ], [ "van Beuzekom", "M.", "" ], [ "Brand", "J. F. J. van den", "" ], [ "Broeck", "C. Van Den", "" ], [ "Vander-Hyde", "D. C.", "" ], [ "van der Schaaf", "L.", "" ], [ "van Heijningen", "J. V.", "" ], [ "van Veggel", "A. A.", "" ], [ "Vardaro", "M.", "" ], [ "Varma", "V.", "" ], [ "Vass", "S.", "" ], [ "Vas'uth", "M.", "" ], [ "Vecchio", "A.", "" ], [ "Vedovato", "G.", "" ], [ "Veitch", "J.", "" ], [ "Veitch", "P. J.", "" ], [ "Venkateswara", "K.", "" ], [ "Venugopalan", "G.", "" ], [ "Verkindt", "D.", "" ], [ "Vetrano", "F.", "" ], [ "Vicer'e", "A.", "" ], [ "Viets", "A. D.", "" ], [ "Vinciguerra", "S.", "" ], [ "Vine", "D. J.", "" ], [ "Vinet", "J. -Y.", "" ], [ "Vitale", "S.", "" ], [ "Vo", "T.", "" ], [ "Vocca", "H.", "" ], [ "Vorvick", "C.", "" ], [ "Vyatchanin", "S. P.", "" ], [ "Wade", "A. R.", "" ], [ "Wade", "L. E.", "" ], [ "Wade", "M.", "" ], [ "Walet", "R.", "" ], [ "Walker", "M.", "" ], [ "Wallace", "L.", "" ], [ "Walsh", "S.", "" ], [ "Wang", "G.", "" ], [ "Wang", "H.", "" ], [ "Wang", "J. Z.", "" ], [ "Wang", "W. H.", "" ], [ "Wang", "Y. F.", "" ], [ "Ward", "R. L.", "" ], [ "Warner", "J.", "" ], [ "Was", "M.", "" ], [ "Watchi", "J.", "" ], [ "Weaver", "B.", "" ], [ "Wei", "L. -W.", "" ], [ "Weinert", "M.", "" ], [ "Weinstein", "A. J.", "" ], [ "Weiss", "R.", "" ], [ "Wen", "L.", "" ], [ "Wessel", "E. K.", "" ], [ "Wessels", "P.", "" ], [ "Westerweck", "J.", "" ], [ "Westphal", "T.", "" ], [ "Wette", "K.", "" ], [ "Whelan", "J. T.", "" ], [ "Whiting", "B. F.", "" ], [ "Whittle", "C.", "" ], [ "Wilken", "D.", "" ], [ "Williams", "D.", "" ], [ "Williams", "R. D.", "" ], [ "Williamson", "A. R.", "" ], [ "Willis", "J. L.", "" ], [ "Willke", "B.", "" ], [ "Wimmer", "M. H.", "" ], [ "Winkler", "W.", "" ], [ "Wipf", "C. C.", "" ], [ "Wittel", "H.", "" ], [ "Woan", "G.", "" ], [ "Woehler", "J.", "" ], [ "Wofford", "J.", "" ], [ "Wong", "K. W. K.", "" ], [ "Worden", "J.", "" ], [ "Wright", "J. L.", "" ], [ "Wu", "D. S.", "" ], [ "Wysocki", "D. M.", "" ], [ "Xiao", "S.", "" ], [ "Yamamoto", "H.", "" ], [ "Yancey", "C. C.", "" ], [ "Yang", "L.", "" ], [ "Yap", "M. J.", "" ], [ "Yazback", "M.", "" ], [ "Yu", "Hang", "" ], [ "Yu", "Haocun", "" ], [ "Yvert", "M.", "" ], [ "zny", "A. Zadro.", "" ], [ "Zanolin", "M.", "" ], [ "Zelenova", "T.", "" ], [ "Zendri", "J. -P.", "" ], [ "Zevin", "M.", "" ], [ "Zhang", "L.", "" ], [ "Zhang", "M.", "" ], [ "Zhang", "T.", "" ], [ "Zhang", "Y. -H.", "" ], [ "Zhao", "C.", "" ], [ "Zhou", "M.", "" ], [ "Zhou", "Z.", "" ], [ "Zhu", "S. J.", "" ], [ "Zhu", "X. J.", "" ], [ "Zucker", "M. E.", "" ], [ "Zweizig", "J.", "" ] ]
Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, {\it narrow-band} analyses methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of eleven pulsars using data from Advanced LIGO's first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched: in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far.
1602.05609
Daniel Boyanovsky
Daniel Boyanovsky
Fermionic influence (action) on inflationary fluctuations
matches published version. arXiv admin note: text overlap with arXiv:1511.06649
Phys. Rev. D 93, 083507 (2016)
10.1103/PhysRevD.93.083507
null
gr-qc astro-ph.CO hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by apparent persistent large scale anomalies in the CMB we study the influence of fermionic degrees of freedom on the dynamics of inflaton fluctuations as a possible source of violations of (nearly) scale invariance on cosmological scales. We obtain the non-equilibrium effective action of an inflaton-like scalar field with Yukawa interactions ($Y_{D,M}$) to light \emph{fermionic} degrees of freedom both for Dirac and Majorana fields in de Sitter space-time. The effective action leads to Langevin equations of motion for the fluctuations of the inflaton-like field, with self-energy corrections and a stochastic gaussian noise. We solve the Langevin equation in the super-Hubble limit implementing a dynamical renormalization group resummation. For a nearly massless inflaton its power spectrum of super Hubble fluctuations is \emph{enhanced}, $\mathcal{P}(k;\eta) = (\frac{H}{2\pi})^2\,e^{\gamma_t[-k\eta] }$ with $\gamma_t[-k\eta] = \frac{1}{6\pi^2} \Big[\sum_{i=1}^{N_D}{Y^2_{i,D}}+2\sum_{j=1}^{N_M}{Y^2_{j,M}}\Big]\,\Big\{\ln^2[-k\eta]-2 \ln[-k\eta]\ln[ -k\eta_0] \Big\} $ for $N_D$ Dirac and $N_M$ Majorana fermions, and $\eta_0$ is the renormalization scale at which the inflaton mass vanishes. The full power spectrum is shown to be renormalization group invariant. These corrections to the super-Hubble power spectrum entail a violation of scale invariance as a consequence of the coupling to the fermionic fields. The effective action is argued to be \emph{exact} in a limit of large number of fermionic fields. A cancellation between the enhancement from fermionic degrees of freedom and suppression from light scalar degrees of freedom \emph{conformally coupled to gravity} suggests the possibility of a finely tuned \emph{supersymmetry} among these fields.
[ { "created": "Wed, 17 Feb 2016 21:53:23 GMT", "version": "v1" }, { "created": "Wed, 13 Apr 2016 14:00:54 GMT", "version": "v2" } ]
2016-04-20
[ [ "Boyanovsky", "Daniel", "" ] ]
Motivated by apparent persistent large scale anomalies in the CMB we study the influence of fermionic degrees of freedom on the dynamics of inflaton fluctuations as a possible source of violations of (nearly) scale invariance on cosmological scales. We obtain the non-equilibrium effective action of an inflaton-like scalar field with Yukawa interactions ($Y_{D,M}$) to light \emph{fermionic} degrees of freedom both for Dirac and Majorana fields in de Sitter space-time. The effective action leads to Langevin equations of motion for the fluctuations of the inflaton-like field, with self-energy corrections and a stochastic gaussian noise. We solve the Langevin equation in the super-Hubble limit implementing a dynamical renormalization group resummation. For a nearly massless inflaton its power spectrum of super Hubble fluctuations is \emph{enhanced}, $\mathcal{P}(k;\eta) = (\frac{H}{2\pi})^2\,e^{\gamma_t[-k\eta] }$ with $\gamma_t[-k\eta] = \frac{1}{6\pi^2} \Big[\sum_{i=1}^{N_D}{Y^2_{i,D}}+2\sum_{j=1}^{N_M}{Y^2_{j,M}}\Big]\,\Big\{\ln^2[-k\eta]-2 \ln[-k\eta]\ln[ -k\eta_0] \Big\} $ for $N_D$ Dirac and $N_M$ Majorana fermions, and $\eta_0$ is the renormalization scale at which the inflaton mass vanishes. The full power spectrum is shown to be renormalization group invariant. These corrections to the super-Hubble power spectrum entail a violation of scale invariance as a consequence of the coupling to the fermionic fields. The effective action is argued to be \emph{exact} in a limit of large number of fermionic fields. A cancellation between the enhancement from fermionic degrees of freedom and suppression from light scalar degrees of freedom \emph{conformally coupled to gravity} suggests the possibility of a finely tuned \emph{supersymmetry} among these fields.
gr-qc/0606023
Yaneer Bar-Yam
Yaneer Bar-Yam
ZM theory IV: Introduction to quantum concepts, Klein-Gordon and Dirac's equations
28 pages, 0 figures
null
null
NECSI Report 2006-06-01
gr-qc hep-th
null
We describe a general approach to the correspondence of ZM theory with quantum electrodynamics. As a first step, we show the correspondence of helical clock-field states with plane wave states of the Dirac equation. Specifically, defining the direction of time as the gradient of the field in the combined field and space dimensions, for constant gradients, results in states that are consistent with conventional plane wave Dirac equation eigenfunctions. Particles and antiparticles, as well as up and down spins are related by axis inversions. The Dirac wavefunction represents the clock-field and the observer defined direction of time and spatial coordinate axes rotation relative to the region of observation. Additional steps showing the correspondence of ZM theory to quantum mechanics and the Dirac equation are deferred to subsequent papers.
[ { "created": "Mon, 5 Jun 2006 02:32:46 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bar-Yam", "Yaneer", "" ] ]
We describe a general approach to the correspondence of ZM theory with quantum electrodynamics. As a first step, we show the correspondence of helical clock-field states with plane wave states of the Dirac equation. Specifically, defining the direction of time as the gradient of the field in the combined field and space dimensions, for constant gradients, results in states that are consistent with conventional plane wave Dirac equation eigenfunctions. Particles and antiparticles, as well as up and down spins are related by axis inversions. The Dirac wavefunction represents the clock-field and the observer defined direction of time and spatial coordinate axes rotation relative to the region of observation. Additional steps showing the correspondence of ZM theory to quantum mechanics and the Dirac equation are deferred to subsequent papers.
1506.05813
Ambrish Raghoonundun
Ambrish M. Raghoonundun and David W. Hobill
Possible Physical Realizations of the Tolman VII solution
Accepted and published in PRD
Phys. Rev. D 92(12) 124005
10.1103/PhysRevD.92.124005
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Tolman VII solution (an exact static spherically symmetric perfect fluid solution) to the Einstein equations is reexamined, and a closed form equation of state (EOS) is deduced for the first time. This EOS allows further analysis leading to a viable model for compact stars to be obtained. Explicit application of causality conditions places further constraints on the model, and recent measurements of masses and radii of neutron stars prove to be within the predictions of the model. It is found that the adiabatic index ${\gamma} \geq 2$, and self-bound crust solutions are not excluded. The solution is also shown to obey known stability criteria. It is argued that this solution provides realistic limits on models of compact stars.
[ { "created": "Thu, 18 Jun 2015 20:23:15 GMT", "version": "v1" }, { "created": "Tue, 1 Dec 2015 21:26:47 GMT", "version": "v2" } ]
2015-12-03
[ [ "Raghoonundun", "Ambrish M.", "" ], [ "Hobill", "David W.", "" ] ]
The Tolman VII solution (an exact static spherically symmetric perfect fluid solution) to the Einstein equations is reexamined, and a closed form equation of state (EOS) is deduced for the first time. This EOS allows further analysis leading to a viable model for compact stars to be obtained. Explicit application of causality conditions places further constraints on the model, and recent measurements of masses and radii of neutron stars prove to be within the predictions of the model. It is found that the adiabatic index ${\gamma} \geq 2$, and self-bound crust solutions are not excluded. The solution is also shown to obey known stability criteria. It is argued that this solution provides realistic limits on models of compact stars.
0812.0012
Yi-Zen Chu
Yi-Zen Chu
The n-body problem in General Relativity up to the second post-Newtonian order from perturbative field theory
39 pages. The Mathematica code used in this paper can be found at http://www.stargazing.net/yizen/PN.html Version 2: Slight re-wording of section on removal of accelerations in 2 PN lagrangian; comments added in conclusion; and typographical errors fixed. Article is similar to that published in PRD
Phys.Rev.D79:044031,2009
10.1103/PhysRevD.79.044031
null
gr-qc astro-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by experimental probes of general relativity, we adopt methods from perturbative (quantum) field theory to compute, up to certain integrals, the effective lagrangian for its n-body problem. Perturbation theory is performed about a background Minkowski spacetime to O[(v/c)^4] beyond Newtonian gravity, where v is the typical speed of these n particles in their center of energy frame. For the specific case of the 2 body problem, the major efforts underway to measure gravitational waves produced by in-spiraling compact astrophysical binaries require their gravitational interactions to be computed beyond the currently known O[(v/c)^7]. We argue that such higher order post-Newtonian calculations must be automated for these field theoretic methods to be applied successfully to achieve this goal. In view of this, we outline an algorithm that would in principle generate the relevant Feynman diagrams to an arbitrary order in v/c and take steps to develop the necessary software. The Feynman diagrams contributing to the n-body effective action at O[(v/c)^6] beyond Newton are derived.
[ { "created": "Sat, 29 Nov 2008 02:15:09 GMT", "version": "v1" }, { "created": "Wed, 25 Feb 2009 17:19:46 GMT", "version": "v2" } ]
2009-03-12
[ [ "Chu", "Yi-Zen", "" ] ]
Motivated by experimental probes of general relativity, we adopt methods from perturbative (quantum) field theory to compute, up to certain integrals, the effective lagrangian for its n-body problem. Perturbation theory is performed about a background Minkowski spacetime to O[(v/c)^4] beyond Newtonian gravity, where v is the typical speed of these n particles in their center of energy frame. For the specific case of the 2 body problem, the major efforts underway to measure gravitational waves produced by in-spiraling compact astrophysical binaries require their gravitational interactions to be computed beyond the currently known O[(v/c)^7]. We argue that such higher order post-Newtonian calculations must be automated for these field theoretic methods to be applied successfully to achieve this goal. In view of this, we outline an algorithm that would in principle generate the relevant Feynman diagrams to an arbitrary order in v/c and take steps to develop the necessary software. The Feynman diagrams contributing to the n-body effective action at O[(v/c)^6] beyond Newton are derived.
2201.04135
Konstantin Zloshchastiev
Konstantin G. Zloshchastiev
On asymptotic behaviour of galactic rotation curves in superfluid vacuum theory
5 pages, 1 figure
Astron. Rep. 65, 1078 (2021)
10.1134/S1063772921100437
null
gr-qc astro-ph.GA
http://creativecommons.org/licenses/by/4.0/
The logarithmic superfluid theory of physical vacuum predicts that gravity is an induced phenomenon, which has a multiple-scale structure. At astronomical scales, as the distance from a gravitating center increases, gravitational potential and corresponding spacetime metric are dominated by a Newtonian (Schwarzschild) term, followed by a logarithmic term, finally by linear and quadratic (de Sitter) terms. Correspondingly, rotation curves are predicted to be Keplerian in the inner regions of galaxies, mostly flat in the outer regions, and non-flat in the utmost outer regions. We compare theory's predictions with the furthest rotation curves data points available for a number of galaxies: using a two-parameter fit, we perform a preliminary estimate which disregards the combined effect of gas and stellar disc, but is relatively simple and uses minimal assumptions for galactic luminous matter. The data strongly points out at the existence of a crossover transition from flat to non-flat regimes at galactic outskirts.
[ { "created": "Tue, 11 Jan 2022 08:30:32 GMT", "version": "v1" } ]
2022-01-13
[ [ "Zloshchastiev", "Konstantin G.", "" ] ]
The logarithmic superfluid theory of physical vacuum predicts that gravity is an induced phenomenon, which has a multiple-scale structure. At astronomical scales, as the distance from a gravitating center increases, gravitational potential and corresponding spacetime metric are dominated by a Newtonian (Schwarzschild) term, followed by a logarithmic term, finally by linear and quadratic (de Sitter) terms. Correspondingly, rotation curves are predicted to be Keplerian in the inner regions of galaxies, mostly flat in the outer regions, and non-flat in the utmost outer regions. We compare theory's predictions with the furthest rotation curves data points available for a number of galaxies: using a two-parameter fit, we perform a preliminary estimate which disregards the combined effect of gas and stellar disc, but is relatively simple and uses minimal assumptions for galactic luminous matter. The data strongly points out at the existence of a crossover transition from flat to non-flat regimes at galactic outskirts.
0709.3074
Patrick Peter
F. Finelli, P. Peter and N. Pinto-Neto
Spectra of primordial fluctuations in two-perfect-fluid regular bounces
11 pages, 5 figures
Phys.Rev.D77:103508,2008
10.1103/PhysRevD.77.103508
null
gr-qc
null
We introduce analytic solutions for a class of two components bouncing models, where the bounce is triggered by a negative energy density perfect fluid. The equation of state of the two components are constant in time, but otherwise unrelated. By numerically integrating regular equations for scalar cosmological perturbations, we find that the (would be) growing mode of the Newtonian potential before the bounce never matches with the the growing mode in the expanding stage. For the particular case of a negative energy density component with a stiff equation of state we give a detailed analytic study, which is in complete agreement with the numerical results. We also perform analytic and numerical calculations for long wavelength tensor perturbations, obtaining that, in most cases of interest, the tensor spectral index is independent of the negative energy fluid and given by the spectral index of the growing mode in the contracting stage. We compare our results with previous investigations in the literature.
[ { "created": "Wed, 19 Sep 2007 17:24:00 GMT", "version": "v1" } ]
2008-11-26
[ [ "Finelli", "F.", "" ], [ "Peter", "P.", "" ], [ "Pinto-Neto", "N.", "" ] ]
We introduce analytic solutions for a class of two components bouncing models, where the bounce is triggered by a negative energy density perfect fluid. The equation of state of the two components are constant in time, but otherwise unrelated. By numerically integrating regular equations for scalar cosmological perturbations, we find that the (would be) growing mode of the Newtonian potential before the bounce never matches with the the growing mode in the expanding stage. For the particular case of a negative energy density component with a stiff equation of state we give a detailed analytic study, which is in complete agreement with the numerical results. We also perform analytic and numerical calculations for long wavelength tensor perturbations, obtaining that, in most cases of interest, the tensor spectral index is independent of the negative energy fluid and given by the spectral index of the growing mode in the contracting stage. We compare our results with previous investigations in the literature.
1310.8312
Pierre-Henry Lambert
Pierre-Henry Lambert
Introduction to Black Hole Evaporation
31 pages, 13 figures, 1 table. Conference proceedings. v2: misprints corrected
PoS(Modave 2013)001
null
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
These lecture notes are an elementary and pedagogical introduction to the black hole evaporation, based on a lecture given by the author at the Ninth Modave Summer School in Mathematical Physics and are intended for PhD students. First, quantum field theory in curved spacetime is studied and tools needed for the remaining of the course are introduced. Then, quantum field theory in Rindler spacetime in 1+1 dimensions and in the spacetime of a spherically collapsing star are considered, leading to Unruh and Hawking effects, respectively. Finally, some consequences such as thermodynamics of black holes and information loss paradox are discussed.
[ { "created": "Wed, 30 Oct 2013 20:21:07 GMT", "version": "v1" }, { "created": "Thu, 16 Jan 2014 16:06:16 GMT", "version": "v2" } ]
2014-01-17
[ [ "Lambert", "Pierre-Henry", "" ] ]
These lecture notes are an elementary and pedagogical introduction to the black hole evaporation, based on a lecture given by the author at the Ninth Modave Summer School in Mathematical Physics and are intended for PhD students. First, quantum field theory in curved spacetime is studied and tools needed for the remaining of the course are introduced. Then, quantum field theory in Rindler spacetime in 1+1 dimensions and in the spacetime of a spherically collapsing star are considered, leading to Unruh and Hawking effects, respectively. Finally, some consequences such as thermodynamics of black holes and information loss paradox are discussed.
1212.0263
James Kentosh
James Kentosh
Localized gravitational energy in a Schwarzschild field
10 pages, 2 figures
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An interpretation of general relativity is developed in which the energy used to lift a body in a static gravitational field increases its rest mass. Observers at different gravitational potentials would experience different mass reference frames. It is shown that bodies falling in a Schwarzschild field exhibit the relativistic mass/energy relationship from special relativity. This new result is independent of the choice of coordinates. The proposed approach provides a physical explanation for gravitational energy, which is localized as a scalar function intrinsic to general relativity. Applying this model to the Robertson-Walker metric demonstrates that time-varying fields induce a net energy transfer between bodies that is not exhibited in static fields.
[ { "created": "Tue, 27 Nov 2012 05:44:51 GMT", "version": "v1" } ]
2012-12-04
[ [ "Kentosh", "James", "" ] ]
An interpretation of general relativity is developed in which the energy used to lift a body in a static gravitational field increases its rest mass. Observers at different gravitational potentials would experience different mass reference frames. It is shown that bodies falling in a Schwarzschild field exhibit the relativistic mass/energy relationship from special relativity. This new result is independent of the choice of coordinates. The proposed approach provides a physical explanation for gravitational energy, which is localized as a scalar function intrinsic to general relativity. Applying this model to the Robertson-Walker metric demonstrates that time-varying fields induce a net energy transfer between bodies that is not exhibited in static fields.
2103.07342
Abhik Kumar Sanyal Dr.
A. Banerjee, S. B. Duttachoudhury and Abhik Kumar Sanyal
Bianchi type I cosmological model with a viscous fluid
9 pages, 0 figures
Journal of Mathematical Physics 26, 3010 (1985)
10.1063/1.526676
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Bianchi I cosmological models consisting of a fluid with both bulk and shear viscosity are studied. It is shown how the dynamical importance of the shear and the fluid density change in the course of evolution. Exact solutions with an equation of state $\rho = p$ for a stiff fluid are also obtained in several special cases, assuming the viscosity coefficients to be the power functions of the density. The results are, in some relevant cases, compared with those of Belinskii and Khalatnikov (1976) in the asymptotic limits and are seen to agree with them in that the models start with $\rho = 0$ at the beginning and evolve with the creation of matter by the gravitational field, finally approaching the Friedmann universe.
[ { "created": "Fri, 12 Mar 2021 15:20:28 GMT", "version": "v1" } ]
2021-03-15
[ [ "Banerjee", "A.", "" ], [ "Duttachoudhury", "S. B.", "" ], [ "Sanyal", "Abhik Kumar", "" ] ]
Bianchi I cosmological models consisting of a fluid with both bulk and shear viscosity are studied. It is shown how the dynamical importance of the shear and the fluid density change in the course of evolution. Exact solutions with an equation of state $\rho = p$ for a stiff fluid are also obtained in several special cases, assuming the viscosity coefficients to be the power functions of the density. The results are, in some relevant cases, compared with those of Belinskii and Khalatnikov (1976) in the asymptotic limits and are seen to agree with them in that the models start with $\rho = 0$ at the beginning and evolve with the creation of matter by the gravitational field, finally approaching the Friedmann universe.
0710.5366
Debashis Gangopadhyay
Debashis Gangopadhyay and Somnath Mukherjee
Logarithm of the scale factor as a generalised coordinate in a lagrangian for dark matter and dark energy
16 pages, latex, paper shortened by 2 pages for journal publication
Phys.Lett.B665:121-124,2008
10.1016/j.physletb.2008.06.025
null
gr-qc astro-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A lagrangian for the $k-$ essence field is set up with canonical kinetic terms and incorporating the scaling relation of [1]. There are two degrees of freedom, {\it viz.},$q(t)= ln\enskip a(t)$ ($a(t)$ is the scale factor) and the scalar field $\phi$, and an interaction term involving $\phi$ and $q(t)$.The Euler-Lagrange equations are solved for $q$ and $\phi$. Using these solutions quantities of cosmological interest are determined. The energy density $\rho$ has a constant component which we identify as dark energy and a component behaving as $a^{-3}$ which we call dark matter. The pressure $p$ is {\it negative} for time $t\to \infty$ and the sound velocity $c_{s}^{2}={\partial p\over\partial\rho} << 1$. When dark energy dominates, the deceleration parameter $Q\to -1$ while in the matter dominated era $Q\sim {1\over 2}$. The equation of state parameter $w={p\over \rho}$ is shown to be consistent with $w={p\over\rho}\sim -1$ for dark energy domination and during the matter dominated era we have $w\sim 0$. Bounds for the parameters of the theory are estimated from observational data. Keywords: k-essence models, dark matter, dark energy PACS No: 98.80.-k
[ { "created": "Mon, 29 Oct 2007 09:51:45 GMT", "version": "v1" }, { "created": "Thu, 14 Aug 2008 05:33:46 GMT", "version": "v2" } ]
2008-11-26
[ [ "Gangopadhyay", "Debashis", "" ], [ "Mukherjee", "Somnath", "" ] ]
A lagrangian for the $k-$ essence field is set up with canonical kinetic terms and incorporating the scaling relation of [1]. There are two degrees of freedom, {\it viz.},$q(t)= ln\enskip a(t)$ ($a(t)$ is the scale factor) and the scalar field $\phi$, and an interaction term involving $\phi$ and $q(t)$.The Euler-Lagrange equations are solved for $q$ and $\phi$. Using these solutions quantities of cosmological interest are determined. The energy density $\rho$ has a constant component which we identify as dark energy and a component behaving as $a^{-3}$ which we call dark matter. The pressure $p$ is {\it negative} for time $t\to \infty$ and the sound velocity $c_{s}^{2}={\partial p\over\partial\rho} << 1$. When dark energy dominates, the deceleration parameter $Q\to -1$ while in the matter dominated era $Q\sim {1\over 2}$. The equation of state parameter $w={p\over \rho}$ is shown to be consistent with $w={p\over\rho}\sim -1$ for dark energy domination and during the matter dominated era we have $w\sim 0$. Bounds for the parameters of the theory are estimated from observational data. Keywords: k-essence models, dark matter, dark energy PACS No: 98.80.-k
1705.04359
Mario Llerena
Andr\'es Ace\~na, Ericson L\'opez, Mario Llerena
An Extreme Rotating Black Hole in New Massive Gravity Theory
null
Revista Polit\'ecnica - Abril 2017, Vol. 39, No. 1
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
New Massive Gravity is an alternative theory to General Relativity that is used to describe the gravitational field in a (2+1)-dimensional spacetime. Black hole solutions have been found in this theory, in particular an asymptotically anti-de Sitter rotating black hole. We analyse some features of this solution as its event horizon, black hole area and distance to the horizon, specially in the rotating extreme case, showing that they have shared features with extreme black holes in 4-dimensional General relativity. This limit case is interesting in the search of geometric inequalities as the ones found for the Kerr black hole in (3+1)-General Relativity.
[ { "created": "Thu, 11 May 2017 19:26:30 GMT", "version": "v1" } ]
2017-05-15
[ [ "Aceña", "Andrés", "" ], [ "López", "Ericson", "" ], [ "Llerena", "Mario", "" ] ]
New Massive Gravity is an alternative theory to General Relativity that is used to describe the gravitational field in a (2+1)-dimensional spacetime. Black hole solutions have been found in this theory, in particular an asymptotically anti-de Sitter rotating black hole. We analyse some features of this solution as its event horizon, black hole area and distance to the horizon, specially in the rotating extreme case, showing that they have shared features with extreme black holes in 4-dimensional General relativity. This limit case is interesting in the search of geometric inequalities as the ones found for the Kerr black hole in (3+1)-General Relativity.
2206.13588
Octavian Micu
Roberto Casadio, Iber\^e Kuntz, Octavian Micu
Binary mergers in bootstrapped Newtonian gravity: mass gap and black hole area law
14 pages, 1 figure, to appear in Phys.Lett.B
null
10.1016/j.physletb.2022.137455
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
We study binary mergers in bootstrapped Newtonian gravity, where higher-order couplings are added to the non-relativistic Lagrangian for the Newtonian potential. In this theory, the Arnowitt-Deser-Misner (ADM) mass differs from both the proper mass of Newtonian gravity and the proper mass of general relativity, which affects the interpretation of astrophysical and cosmological events. The aforementioned difference particularly provides important phenomenological constraints for the mass of the emitted matter and the compactness of the final object after the merger. The interpretation of the GW150914 signal in this theory also shows that LIGO's findings do not violate the mass gap, contrary to usual claims. We indeed find that typical stellar black hole masses can fit LIGO's data for a considerable range of compactness values. We calculate the black hole entropy in this context, which leads to a generalised black hole area law. Non-linear effects are found to effectively change only the gravitational strength via the renormalization of Newton's constant in this case.
[ { "created": "Mon, 27 Jun 2022 19:08:15 GMT", "version": "v1" }, { "created": "Wed, 14 Sep 2022 08:24:41 GMT", "version": "v2" } ]
2022-09-21
[ [ "Casadio", "Roberto", "" ], [ "Kuntz", "Iberê", "" ], [ "Micu", "Octavian", "" ] ]
We study binary mergers in bootstrapped Newtonian gravity, where higher-order couplings are added to the non-relativistic Lagrangian for the Newtonian potential. In this theory, the Arnowitt-Deser-Misner (ADM) mass differs from both the proper mass of Newtonian gravity and the proper mass of general relativity, which affects the interpretation of astrophysical and cosmological events. The aforementioned difference particularly provides important phenomenological constraints for the mass of the emitted matter and the compactness of the final object after the merger. The interpretation of the GW150914 signal in this theory also shows that LIGO's findings do not violate the mass gap, contrary to usual claims. We indeed find that typical stellar black hole masses can fit LIGO's data for a considerable range of compactness values. We calculate the black hole entropy in this context, which leads to a generalised black hole area law. Non-linear effects are found to effectively change only the gravitational strength via the renormalization of Newton's constant in this case.
gr-qc/9609013
Ramy Brustein
Bruce Allen, Ram Brustein
Detecting relic gravitational radiation from string cosmology with LIGO
6 pages, 5 eps figures, Revtex
Phys.Rev.D55:3260-3264,1997
10.1103/PhysRevD.55.3260
WISC-MILW-96-TH-34,BGU-PH-96/09
gr-qc astro-ph hep-th
null
A characteristic spectrum of relic gravitational radiation is produced by a period of ``stringy inflation" in the early universe. This spectrum is unusual, because the energy-density rises rapidly with frequency. We show that correlation experiments with the two gravitational wave detectors being built for the Laser Interferometric Gravitational Observatory (LIGO) could detect this relic radiation, for certain ranges of the parameters that characterize the underlying string cosmology model.
[ { "created": "Thu, 5 Sep 1996 06:03:38 GMT", "version": "v1" } ]
2009-12-30
[ [ "Allen", "Bruce", "" ], [ "Brustein", "Ram", "" ] ]
A characteristic spectrum of relic gravitational radiation is produced by a period of ``stringy inflation" in the early universe. This spectrum is unusual, because the energy-density rises rapidly with frequency. We show that correlation experiments with the two gravitational wave detectors being built for the Laser Interferometric Gravitational Observatory (LIGO) could detect this relic radiation, for certain ranges of the parameters that characterize the underlying string cosmology model.
2010.04943
Shao-Jiang Wang
Rong-Gen Cai, Shao-Jiang Wang, Su Yi, Jiang-Hao Yu
Testing weakest force with coldest spot
v1, 10 pages, 3 figures; v2, references added, discussion extended for enlarged parameter space of Yukawa interaction, version accepted by EPJC
Eur. Phys. J. C 81, 318 (2021)
10.1140/epjc/s10052-021-09102-y
null
gr-qc cond-mat.quant-gas
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ultra-cold atom experiment in space with microgravity allows for realization of dilute atomic-gas Bose-Einstein condensate (BEC) with macroscopically large occupation number and significantly long condensate lifetime, which allows for a precise measurement on the shape oscillation frequency by calibrating itself over numerous oscillation periods. In this paper, we propose to measure the Newtonian gravitational constant via ultra-cold atom BEC with shape oscillation, although it is experimentally challenging. We also make a preliminary perspective on constraining the modified Newtonian potential such as the power-law potential, Yukawa interaction, and fat graviton. A resolution of frequency measurement of $(1-100)\,\mathrm{nHz}$ at most for the occupation number $10^9$, just one order above experimentally achievable number $N\sim10^6-10^8$, is feasible to constrain the modified Newtonian potential with Yukawa interaction greatly beyond the current exclusion limits.
[ { "created": "Sat, 10 Oct 2020 08:41:05 GMT", "version": "v1" }, { "created": "Wed, 31 Mar 2021 02:43:50 GMT", "version": "v2" } ]
2021-04-20
[ [ "Cai", "Rong-Gen", "" ], [ "Wang", "Shao-Jiang", "" ], [ "Yi", "Su", "" ], [ "Yu", "Jiang-Hao", "" ] ]
Ultra-cold atom experiment in space with microgravity allows for realization of dilute atomic-gas Bose-Einstein condensate (BEC) with macroscopically large occupation number and significantly long condensate lifetime, which allows for a precise measurement on the shape oscillation frequency by calibrating itself over numerous oscillation periods. In this paper, we propose to measure the Newtonian gravitational constant via ultra-cold atom BEC with shape oscillation, although it is experimentally challenging. We also make a preliminary perspective on constraining the modified Newtonian potential such as the power-law potential, Yukawa interaction, and fat graviton. A resolution of frequency measurement of $(1-100)\,\mathrm{nHz}$ at most for the occupation number $10^9$, just one order above experimentally achievable number $N\sim10^6-10^8$, is feasible to constrain the modified Newtonian potential with Yukawa interaction greatly beyond the current exclusion limits.
2303.00297
Umananda Dev Goswami
Ronit Karmakar, Dhruba Jyoti Gogoi and Umananda Dev Goswami
Thermodynamics and Shadows of GUP-corrected Black Holes with Topological Defects in Bumblebee Gravity
20 pages, 10 figures; Accepted version of Physics of the Dark Universe
Phys. Dark Universe 41, 101249 (2023)
10.1016/j.dark.2023.101249
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
In this work we investigate a Schwarzschild-type black hole that is corrected by the Generalized Uncertainty Principle (GUP) and possesses topological defects within the framework of Bumblebee gravity. Our focus is on the thermodynamic characteristics of the black hole, such as temperature, entropy and heat capacity, which vary as functions of the horizon radius, and also on shadow as an optical feature. Our investigation reveals significant changes in the thermodynamic behavior of the black hole due to violations of Lorentz symmetry, GUP corrections, and the presence of monopoles. However, the shadow of the black hole is unaffected by violations of Lorentz symmetry. In addition, we provide a limit on the parameters of Lorentz symmetry violation, GUP and topological defects based on a classical test involving the precession of planetary orbits and the advancement of perihelion in the solar system.
[ { "created": "Wed, 1 Mar 2023 07:47:07 GMT", "version": "v1" }, { "created": "Sun, 14 May 2023 11:39:27 GMT", "version": "v2" } ]
2023-05-16
[ [ "Karmakar", "Ronit", "" ], [ "Gogoi", "Dhruba Jyoti", "" ], [ "Goswami", "Umananda Dev", "" ] ]
In this work we investigate a Schwarzschild-type black hole that is corrected by the Generalized Uncertainty Principle (GUP) and possesses topological defects within the framework of Bumblebee gravity. Our focus is on the thermodynamic characteristics of the black hole, such as temperature, entropy and heat capacity, which vary as functions of the horizon radius, and also on shadow as an optical feature. Our investigation reveals significant changes in the thermodynamic behavior of the black hole due to violations of Lorentz symmetry, GUP corrections, and the presence of monopoles. However, the shadow of the black hole is unaffected by violations of Lorentz symmetry. In addition, we provide a limit on the parameters of Lorentz symmetry violation, GUP and topological defects based on a classical test involving the precession of planetary orbits and the advancement of perihelion in the solar system.
1602.04779
Shantanu Desai
Emre O. Kahya, Shantanu Desai
Constraints on frequency-dependent violations of Shapiro delay from GW150914
3 pages, accepted for publication in Phys. Lett. B. This paper is dedicated to the memory of Prof. Steven Detweiler
Phys. Lett. B 756, 265 (2016)
10.1016/j.physletb.2016.03.033
null
gr-qc astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
On 14th September 2015, a transient gravitational wave (GW150914) was detected by the two LIGO detectors at Hanford and Livingston from the coalescence of a binary black hole system located at a distance of about 400 Mpc. We point out that GW150914 experienced a Shapiro delay due to the gravitational potential of the mass distribution along the line of sight of about 1800 days. Also, the near-simultaneous arrival of gravitons over a frequency range of about 100 Hz within a 0.2 second window allows us to constrain any violations of Shapiro delay and Einstein's equivalence principle between the gravitons at different frequencies. From the calculated Shapiro delay and the observed duration of the signal, frequency-dependent violations of the equivalence principle for gravitons are constrained to an accuracy of $\mathcal{O}(10^{-9})$
[ { "created": "Mon, 15 Feb 2016 19:54:36 GMT", "version": "v1" }, { "created": "Wed, 17 Feb 2016 21:24:59 GMT", "version": "v2" }, { "created": "Wed, 16 Mar 2016 22:37:36 GMT", "version": "v3" } ]
2016-03-25
[ [ "Kahya", "Emre O.", "" ], [ "Desai", "Shantanu", "" ] ]
On 14th September 2015, a transient gravitational wave (GW150914) was detected by the two LIGO detectors at Hanford and Livingston from the coalescence of a binary black hole system located at a distance of about 400 Mpc. We point out that GW150914 experienced a Shapiro delay due to the gravitational potential of the mass distribution along the line of sight of about 1800 days. Also, the near-simultaneous arrival of gravitons over a frequency range of about 100 Hz within a 0.2 second window allows us to constrain any violations of Shapiro delay and Einstein's equivalence principle between the gravitons at different frequencies. From the calculated Shapiro delay and the observed duration of the signal, frequency-dependent violations of the equivalence principle for gravitons are constrained to an accuracy of $\mathcal{O}(10^{-9})$
0801.1204
Narayan Banerjee
Narayan Banerjee, Sudipta Das, Koyel Ganguly
Chameleon field and the late time acceleration of the universe
7 pages, 2 figures
Pramana 74:L481-L489,2010
10.1007/s12043-010-0044-5
null
gr-qc astro-ph
null
In the present work, it is shown that a chameleon scalar field having a nonminimal coupling with dark matter can give rise to a smooth transition from a decelerated to an accelerated phase of expansion for the universe. It is surprising to note that the coupling with the chameleon scalar field hardly affects the evolution of the dark matter sector, which still redshifts as $a^{-3}$.
[ { "created": "Tue, 8 Jan 2008 11:09:56 GMT", "version": "v1" } ]
2015-05-13
[ [ "Banerjee", "Narayan", "" ], [ "Das", "Sudipta", "" ], [ "Ganguly", "Koyel", "" ] ]
In the present work, it is shown that a chameleon scalar field having a nonminimal coupling with dark matter can give rise to a smooth transition from a decelerated to an accelerated phase of expansion for the universe. It is surprising to note that the coupling with the chameleon scalar field hardly affects the evolution of the dark matter sector, which still redshifts as $a^{-3}$.
gr-qc/0102051
Carlo Rovelli
Etera R. Livine, Alejandro Perez, Carlo Rovelli
2d manifold-independent spinfoam theory
31 pages, five figures; v2: details and one reference added
null
null
null
gr-qc
null
A number of background independent quantizations procedures have recently been employed in 4d nonperturbative quantum gravity. We investigate and illustrate these techniques and their relation in the context of a simple 2d topological theory. We discuss canonical quantization, loop or spin network states, path integral quantization over a discretization of the manifold, spin foam formulation, as well as the fully background independent definition of the theory using an auxiliary field theory on a group manifold. While several of these techniques have already been applied to this theory by Witten, the last one is novel: it allows us to give a precise meaning to the sum over topologies, and to compute background-independent and, in fact, "manifold-independent" transition amplitudes. These transition amplitudes play the role of Wightman functions of the theory. They are physical observable quantities, and the canonical structure of the theory can be reconstructed from them via a C* algebraic GNS construction. We expect an analogous structure to be relevant in 4d quantum gravity.
[ { "created": "Mon, 12 Feb 2001 19:38:15 GMT", "version": "v1" }, { "created": "Fri, 16 May 2003 09:25:09 GMT", "version": "v2" } ]
2007-05-23
[ [ "Livine", "Etera R.", "" ], [ "Perez", "Alejandro", "" ], [ "Rovelli", "Carlo", "" ] ]
A number of background independent quantizations procedures have recently been employed in 4d nonperturbative quantum gravity. We investigate and illustrate these techniques and their relation in the context of a simple 2d topological theory. We discuss canonical quantization, loop or spin network states, path integral quantization over a discretization of the manifold, spin foam formulation, as well as the fully background independent definition of the theory using an auxiliary field theory on a group manifold. While several of these techniques have already been applied to this theory by Witten, the last one is novel: it allows us to give a precise meaning to the sum over topologies, and to compute background-independent and, in fact, "manifold-independent" transition amplitudes. These transition amplitudes play the role of Wightman functions of the theory. They are physical observable quantities, and the canonical structure of the theory can be reconstructed from them via a C* algebraic GNS construction. We expect an analogous structure to be relevant in 4d quantum gravity.
1104.4972
Michael Reiterer
Michael Reiterer (ETH Zurich), Eugene Trubowitz (ETH Zurich)
A class of gauges for the Einstein equations
12 pages, Subsection 4.4 simplified
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A class of gauges for the Einstein vacuum equations is introduced, along with three symmetric hyperbolic systems. The first implies the local realizability of the gauge. The second is the dynamical subset of the field equations. The third is used to show that the constraints propagate. The gauges are for an orthonormal frame formalism, with first order, quadratically nonlinear equations. The unknowns are 16 frame components and 28 connection components. After gauge-fixing, a total of 33 remain.
[ { "created": "Tue, 26 Apr 2011 17:19:10 GMT", "version": "v1" }, { "created": "Sat, 30 Apr 2011 17:08:46 GMT", "version": "v2" } ]
2011-05-03
[ [ "Reiterer", "Michael", "", "ETH Zurich" ], [ "Trubowitz", "Eugene", "", "ETH Zurich" ] ]
A class of gauges for the Einstein vacuum equations is introduced, along with three symmetric hyperbolic systems. The first implies the local realizability of the gauge. The second is the dynamical subset of the field equations. The third is used to show that the constraints propagate. The gauges are for an orthonormal frame formalism, with first order, quadratically nonlinear equations. The unknowns are 16 frame components and 28 connection components. After gauge-fixing, a total of 33 remain.
1609.01477
Chandra Prakash Singh
C P Singh and Pankaj Kumar
Holographic dark energy in Brans-Dicke theory with logarithmic form of scalar field
9 pages, 5 figures
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, an interacting holographic dark energy model with Hubble horizon as an infra-red cut-off is considered in the framework of Brans-Dicke theory. We propose a logarithmic form $\phi \propto ln(\alpha+\beta a)$ of the Brans-Dicke scalar field to alleviate the problems of interacting holographic dark energy models in Brans-Dicke theory. We find that the equation of state parameter $w_h$ and deceleration parameter $q$ are negative in the early time which shows the early time inflation. During the evolution the sign of parameter $q$ changes from negative to positive which means that the Universe expands with decelerated rate whereas the sign of $w_h$ may change or remain negative throughout the evolution depending on the values of parameters. It is also observed that $w_h$ may cross the phantom divide line in the late time evolution. The sign of $q$ changes from positive to negative during late time of evolution which explains the late time accelerated expansion of the Universe. Thus, we present a unified model of holographic dark energy which explains the early time acceleration (inflation), medieval time deceleration and late time acceleration. We also discuss the cosmic coincidence problem. We obtain a time-varying density ratio of holographic dark energy to dark matter which is a constant of order one ($r\sim \mathcal{O}(1)$) during early and late time evolution. Therefore, our model successfully resolves the cosmic coincidence problem.
[ { "created": "Tue, 6 Sep 2016 10:22:58 GMT", "version": "v1" } ]
2016-09-07
[ [ "Singh", "C P", "" ], [ "Kumar", "Pankaj", "" ] ]
In this paper, an interacting holographic dark energy model with Hubble horizon as an infra-red cut-off is considered in the framework of Brans-Dicke theory. We propose a logarithmic form $\phi \propto ln(\alpha+\beta a)$ of the Brans-Dicke scalar field to alleviate the problems of interacting holographic dark energy models in Brans-Dicke theory. We find that the equation of state parameter $w_h$ and deceleration parameter $q$ are negative in the early time which shows the early time inflation. During the evolution the sign of parameter $q$ changes from negative to positive which means that the Universe expands with decelerated rate whereas the sign of $w_h$ may change or remain negative throughout the evolution depending on the values of parameters. It is also observed that $w_h$ may cross the phantom divide line in the late time evolution. The sign of $q$ changes from positive to negative during late time of evolution which explains the late time accelerated expansion of the Universe. Thus, we present a unified model of holographic dark energy which explains the early time acceleration (inflation), medieval time deceleration and late time acceleration. We also discuss the cosmic coincidence problem. We obtain a time-varying density ratio of holographic dark energy to dark matter which is a constant of order one ($r\sim \mathcal{O}(1)$) during early and late time evolution. Therefore, our model successfully resolves the cosmic coincidence problem.
2004.13492
S. I. Kruglov
S. I. Kruglov
Universe Inflation Based on Nonlinear Electrodynamics
22 pages, 7 figures. 1 table
Eur. Phys. J. Plus 135, 370 (2020)
10.1140/epjp/s13360-020-00377-w
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A new model of nonlinear electrodynamics with dimensional parameters $\beta$ and $\gamma$ is proposed. The principles of causality and unitarity are studied. We show that a singularity of the electric field at the origin of charges is absent and the maximum of the electric field in the center is $E(0)=1/\sqrt{\beta}$. The dual symmetry is broken in our model. Corrections to the Coulomb law as $r\rightarrow\infty$ are in the order of ${\cal O}(r^{-4})$. The source of the gravitation field and inflation of the universe is electromagnetic fields. It is supposed that the universe is filled by stochastic magnetic fields. We demonstrate that after the universe inflation the universe decelerates approaching the Minkowski spacetime. The singularities of the Ricci scalar, the Ricci tensor squared and the Kretschmann scalar are absent. We calculate the speed of sound. The spectral index, the tensor-to-scalar ratio, and the running of the spectral index, which approximately agree with the PLANK and WMAP data, are evaluated.
[ { "created": "Sun, 26 Apr 2020 22:37:31 GMT", "version": "v1" } ]
2020-04-29
[ [ "Kruglov", "S. I.", "" ] ]
A new model of nonlinear electrodynamics with dimensional parameters $\beta$ and $\gamma$ is proposed. The principles of causality and unitarity are studied. We show that a singularity of the electric field at the origin of charges is absent and the maximum of the electric field in the center is $E(0)=1/\sqrt{\beta}$. The dual symmetry is broken in our model. Corrections to the Coulomb law as $r\rightarrow\infty$ are in the order of ${\cal O}(r^{-4})$. The source of the gravitation field and inflation of the universe is electromagnetic fields. It is supposed that the universe is filled by stochastic magnetic fields. We demonstrate that after the universe inflation the universe decelerates approaching the Minkowski spacetime. The singularities of the Ricci scalar, the Ricci tensor squared and the Kretschmann scalar are absent. We calculate the speed of sound. The spectral index, the tensor-to-scalar ratio, and the running of the spectral index, which approximately agree with the PLANK and WMAP data, are evaluated.
1110.3878
Shinji Tsujikawa
Antonio De Felice, Shinji Tsujikawa
Conditions for the cosmological viability of the most general scalar-tensor theories and their applications to extended Galileon dark energy models
18 pages, 6 figures
JCAP 1202:007, 2012
10.1088/1475-7516/2012/02/007
null
gr-qc astro-ph.CO hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the Horndeski's most general scalar-tensor theories with second-order field equations, we derive the conditions for the avoidance of ghosts and Laplacian instabilities associated with scalar, tensor, and vector perturbations in the presence of two perfect fluids on the flat Friedmann-Lemaitre-Robertson-Walker (FLRW) background. Our general results are useful for the construction of theoretically consistent models of dark energy. We apply our formulas to extended Galileon models in which a tracker solution with an equation of state smaller than -1 is present. We clarify the allowed parameter space in which the ghosts and Laplacian instabilities are absent and we numerically confirm that such models are indeed cosmologically viable.
[ { "created": "Tue, 18 Oct 2011 05:22:45 GMT", "version": "v1" } ]
2015-05-30
[ [ "De Felice", "Antonio", "" ], [ "Tsujikawa", "Shinji", "" ] ]
In the Horndeski's most general scalar-tensor theories with second-order field equations, we derive the conditions for the avoidance of ghosts and Laplacian instabilities associated with scalar, tensor, and vector perturbations in the presence of two perfect fluids on the flat Friedmann-Lemaitre-Robertson-Walker (FLRW) background. Our general results are useful for the construction of theoretically consistent models of dark energy. We apply our formulas to extended Galileon models in which a tracker solution with an equation of state smaller than -1 is present. We clarify the allowed parameter space in which the ghosts and Laplacian instabilities are absent and we numerically confirm that such models are indeed cosmologically viable.
2206.08037
Ulf Lindstr\"om
Ulf Lindstr\"om and \"Ozg\"ur Sar{\i}o\u{g}lu
Geometry, conformal Killing-Yano tensors and conserved "currents"
15 pages; This version considerably reworked relative to previous ones, prompted by a number of comments from various researchers
JHEP 05 (2023) 176
10.1007/JHEP05(2023)176
Uppsala Theoretical Physics preprint UUUIP-27/22
gr-qc hep-th
http://creativecommons.org/licenses/by/4.0/
In this paper we discuss the construction of conserved tensors (currents) involving conformal Killing-Yano tensors (CKYTs), generalising the corresponding constructions for Killing-Yano tensors (KYTs). As a useful preparation for this, but also of intrinsic interest, we derive identities relating CKYTs and geometric quantities. The behaviour of CKYTs under conformal transformations is also given, correcting formulae in the literature. We then use the identities derived to construct covariantly conserved ``currents''. We find several new CKYT currents and also include a known one by Penrose which shows that ``trivial'' currents are also useful. We further find that rank-$n$ currents based on rank-$n$ CKYTs $k$ must have a simple form in terms of $dk$. By construction, these currents are covariant under a general conformal rescaling of the metric. How currents lead to conserved charges is then illustrated using the Kerr-Newman and the C-metric in four dimensions. Separately, we study a rank-1 current, construct its charge and discuss its relation to the recently constructed Cotton current for the Kerr-Newman black hole.
[ { "created": "Thu, 16 Jun 2022 09:42:36 GMT", "version": "v1" }, { "created": "Sun, 5 Mar 2023 16:15:20 GMT", "version": "v2" } ]
2023-05-24
[ [ "Lindström", "Ulf", "" ], [ "Sarıoğlu", "Özgür", "" ] ]
In this paper we discuss the construction of conserved tensors (currents) involving conformal Killing-Yano tensors (CKYTs), generalising the corresponding constructions for Killing-Yano tensors (KYTs). As a useful preparation for this, but also of intrinsic interest, we derive identities relating CKYTs and geometric quantities. The behaviour of CKYTs under conformal transformations is also given, correcting formulae in the literature. We then use the identities derived to construct covariantly conserved ``currents''. We find several new CKYT currents and also include a known one by Penrose which shows that ``trivial'' currents are also useful. We further find that rank-$n$ currents based on rank-$n$ CKYTs $k$ must have a simple form in terms of $dk$. By construction, these currents are covariant under a general conformal rescaling of the metric. How currents lead to conserved charges is then illustrated using the Kerr-Newman and the C-metric in four dimensions. Separately, we study a rank-1 current, construct its charge and discuss its relation to the recently constructed Cotton current for the Kerr-Newman black hole.
1008.2768
Stephen D. H. Hsu
Roberto Casadio, Stephen D.H. Hsu, Behrouz Mirza
Asymptotic Safety, Singularities, and Gravitational Collapse
6 pages, latex. Version to appear in Physics Letters B
Phys.Lett.B695:317-319,2011
10.1016/j.physletb.2010.10.060
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Asymptotic safety (an ultraviolet fixed point with finite-dimensional critical surface) offers the possibility that a predictive theory of quantum gravity can be obtained from the quantization of classical general relativity. However, it is unclear what becomes of the singularities of classical general relativity, which, it is hoped, might be resolved by quantum effects. We study dust collapse with a running gravitational coupling and find that a future singularity can be avoided if the coupling becomes exactly zero at some finite energy scale. The singularity can also be avoided (pushed off to infinite proper time) if the coupling approaches zero sufficiently rapidly at high energies. However, the evolution deduced from perturbation theory still implies a singularity at finite proper time.
[ { "created": "Mon, 16 Aug 2010 20:18:47 GMT", "version": "v1" }, { "created": "Wed, 3 Nov 2010 08:35:30 GMT", "version": "v2" } ]
2011-06-27
[ [ "Casadio", "Roberto", "" ], [ "Hsu", "Stephen D. H.", "" ], [ "Mirza", "Behrouz", "" ] ]
Asymptotic safety (an ultraviolet fixed point with finite-dimensional critical surface) offers the possibility that a predictive theory of quantum gravity can be obtained from the quantization of classical general relativity. However, it is unclear what becomes of the singularities of classical general relativity, which, it is hoped, might be resolved by quantum effects. We study dust collapse with a running gravitational coupling and find that a future singularity can be avoided if the coupling becomes exactly zero at some finite energy scale. The singularity can also be avoided (pushed off to infinite proper time) if the coupling approaches zero sufficiently rapidly at high energies. However, the evolution deduced from perturbation theory still implies a singularity at finite proper time.
2406.01998
Andronikos Paliathanasis
Andronikos Paliathanasis
The Common Solution Space of General Relativity
20 pages, no figures
null
null
null
gr-qc hep-th math-ph math.MP
http://creativecommons.org/licenses/by/4.0/
We review the solution space for the field equations of Einstein's General Relativity for various static, spherically symmetric spacetimes. We consider the vacuum case, represented by the Schwarzschild black hole; the de Sitter-Schwarzschild geometry, which includes a cosmological constant; the Reissner-Nordstr\"{o}m geometry, which accounts for the presence of charge. Additionally we consider the homogenenous and anisotropic locally rotational Bianchi II spacetime in the vacuum. Our analysis reveals that the field equations for these scenarios share a common three-dimensional group of point transformations, with the generators being the elements of the $D\otimes_{s}T_{2}$ Lie algebra, known as the semidirect product of dilations and translations in the plane. Due to this algebraic property the field equations for the aforementioned gravitational models can be expressed in the equivalent form of the null geodesic equations for conformally flat geometries. Consequently, the solution space for the field equations is common, and it is the solution space for the free particle in a flat space. This appoach open new directions on the construction of analytic solutions in gravitational physics and cosmology.
[ { "created": "Tue, 4 Jun 2024 06:28:15 GMT", "version": "v1" } ]
2024-06-05
[ [ "Paliathanasis", "Andronikos", "" ] ]
We review the solution space for the field equations of Einstein's General Relativity for various static, spherically symmetric spacetimes. We consider the vacuum case, represented by the Schwarzschild black hole; the de Sitter-Schwarzschild geometry, which includes a cosmological constant; the Reissner-Nordstr\"{o}m geometry, which accounts for the presence of charge. Additionally we consider the homogenenous and anisotropic locally rotational Bianchi II spacetime in the vacuum. Our analysis reveals that the field equations for these scenarios share a common three-dimensional group of point transformations, with the generators being the elements of the $D\otimes_{s}T_{2}$ Lie algebra, known as the semidirect product of dilations and translations in the plane. Due to this algebraic property the field equations for the aforementioned gravitational models can be expressed in the equivalent form of the null geodesic equations for conformally flat geometries. Consequently, the solution space for the field equations is common, and it is the solution space for the free particle in a flat space. This appoach open new directions on the construction of analytic solutions in gravitational physics and cosmology.
2206.02046
Valerio Faraoni
Valerio Faraoni, Andrea Giusti, Sonia Jose, Serena Giardino
Peculiar thermal states in the first-order thermodynamics of gravity
10 pages, latex
null
10.1103/PhysRevD.106.024049
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the context of the recently proposed first-order thermodynamics of scalar-tensor gravity, we discuss the possibility of zero-temperature states of equilibrium other than Einstein gravity, including pathological Brans-Dicke theory, Palatini $f(R)$ gravity, and cuscuton gravity, all with non-dynamical scalar fields. The formalism is extended to Nordstr\"om gravity, which contains only a scalar degree of freedom and has negative temperature relative to general relativity.
[ { "created": "Sat, 4 Jun 2022 19:20:26 GMT", "version": "v1" } ]
2022-08-17
[ [ "Faraoni", "Valerio", "" ], [ "Giusti", "Andrea", "" ], [ "Jose", "Sonia", "" ], [ "Giardino", "Serena", "" ] ]
In the context of the recently proposed first-order thermodynamics of scalar-tensor gravity, we discuss the possibility of zero-temperature states of equilibrium other than Einstein gravity, including pathological Brans-Dicke theory, Palatini $f(R)$ gravity, and cuscuton gravity, all with non-dynamical scalar fields. The formalism is extended to Nordstr\"om gravity, which contains only a scalar degree of freedom and has negative temperature relative to general relativity.
2310.14411
Andrei Lebed G
Andrei G. Lebed
Violation of the Einstein's Equivalence Principle for a Composite Quantum Body
4 pages
AIP Conf. Proc. 2872, 120048 (2023)
null
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
Recently, we have started to investigate behavior of a composite quantum body in an external gravitational field in the framework of General Relativity [see, for a review, A. G. Lebed, Mod. Phys. Lett. A, {\bf 35}, 2030010 (2020)]. As the simplest example, we have considered a hydrogen atom in a weak gravitational field. Our results are the following. The Einstein's Equivalence Principle survives for the most of macroscopic ensembles of the atoms, containing the stationary quantum states. On the other hand, we have demonstrated that this principle is sometimes broken. In particular, it is broken for the so-called Gravitational demons, which are the coherent macroscopic ensembles of two or more stationary quantum states in the hydrogen atoms. In the above cited paper we have considered the Gedanken experiment, where the gravitational field is suddenly switched on in a free from gravitation space. In the current paper we consider the much more realistic from experimental point of view Gedanken experiment and come to the same conclusion about violations of the Einstein's Equivalence Principle for the Gravitational demons.
[ { "created": "Sun, 22 Oct 2023 20:52:20 GMT", "version": "v1" } ]
2023-10-24
[ [ "Lebed", "Andrei G.", "" ] ]
Recently, we have started to investigate behavior of a composite quantum body in an external gravitational field in the framework of General Relativity [see, for a review, A. G. Lebed, Mod. Phys. Lett. A, {\bf 35}, 2030010 (2020)]. As the simplest example, we have considered a hydrogen atom in a weak gravitational field. Our results are the following. The Einstein's Equivalence Principle survives for the most of macroscopic ensembles of the atoms, containing the stationary quantum states. On the other hand, we have demonstrated that this principle is sometimes broken. In particular, it is broken for the so-called Gravitational demons, which are the coherent macroscopic ensembles of two or more stationary quantum states in the hydrogen atoms. In the above cited paper we have considered the Gedanken experiment, where the gravitational field is suddenly switched on in a free from gravitation space. In the current paper we consider the much more realistic from experimental point of view Gedanken experiment and come to the same conclusion about violations of the Einstein's Equivalence Principle for the Gravitational demons.
gr-qc/0608074
John W. Moffat
J. W. Moffat
A Modified Gravity and its Consequences for the Solar System, Astrophysics and Cosmology
16 pages. Latex file. Talk given at the International Workshop "From Quantum to Cosmos: Fundamental Physics in Space", 22-24 May, 2006, Warrenton, Virginia, USA. To be published in Int. J. Mod. Phys D. Equation corrected
Int.J.Mod.Phys.D16:2075-2090,2008
10.1142/S0218271807011577
null
gr-qc
null
A relativistic modified gravity (MOG) theory leads to a self-consistent, stable gravity theory that can describe the solar system, galaxy and clusters of galaxies data and cosmology.
[ { "created": "Tue, 15 Aug 2006 22:41:03 GMT", "version": "v1" }, { "created": "Sun, 17 Dec 2006 21:56:02 GMT", "version": "v2" } ]
2008-11-26
[ [ "Moffat", "J. W.", "" ] ]
A relativistic modified gravity (MOG) theory leads to a self-consistent, stable gravity theory that can describe the solar system, galaxy and clusters of galaxies data and cosmology.
1608.07521
Arick Shao
Gustav Holzegel, Arick Shao
Unique continuation from infinity in asympotically Anti-de Sitter spacetimes II: Non-static boundaries
45 pages. Newest version incorporated changes from referee comments and fixed minor typos
null
10.1080/03605302.2017.1390677
null
gr-qc math.AP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We generalize our unique continuation results recently established for a class of linear and nonlinear wave equations $\Box_g \phi + \sigma \phi = \mathcal{G} ( \phi, \partial \phi )$ on asymptotically anti-de Sitter (aAdS) spacetimes to aAdS spacetimes admitting non-static boundary metrics. The new Carleman estimates established in this setting constitute an essential ingredient in proving unique continuation results for the full nonlinear Einstein equations, which will be addressed in forthcoming papers. Key to the proof is a new geometrically adapted construction of foliations of pseudoconvex hypersurfaces near the conformal boundary.
[ { "created": "Fri, 26 Aug 2016 16:53:24 GMT", "version": "v1" }, { "created": "Tue, 28 Nov 2017 16:59:08 GMT", "version": "v2" } ]
2017-11-29
[ [ "Holzegel", "Gustav", "" ], [ "Shao", "Arick", "" ] ]
We generalize our unique continuation results recently established for a class of linear and nonlinear wave equations $\Box_g \phi + \sigma \phi = \mathcal{G} ( \phi, \partial \phi )$ on asymptotically anti-de Sitter (aAdS) spacetimes to aAdS spacetimes admitting non-static boundary metrics. The new Carleman estimates established in this setting constitute an essential ingredient in proving unique continuation results for the full nonlinear Einstein equations, which will be addressed in forthcoming papers. Key to the proof is a new geometrically adapted construction of foliations of pseudoconvex hypersurfaces near the conformal boundary.
gr-qc/0209112
Barrabes
C. Barrabes, P.A. Hogan
A Class of Collisions of Plane Impulsive Light--Like Signals in General Relativity
14 pages, lateX
Int.J.Mod.Phys. D11 (2002) 933-945
10.1142/S0218271802002116
null
gr-qc
null
We present a systematic study of collisions of homogeneous, plane--fronted, impulsive light--like signals which do not interact after head--on collision. For the head--on collision of two such signals, six real parameters are involved, three from each of the incoming signals. We find two necessary conditions to be satisfied by these six parameters for the signals to be non--interacting after collision. We then solve the collision problem in general when these necessary conditions hold. After collision the two signals focus each other at Weyl curvature singularities on each others signal front. Our family of solutions contains some known collision solutions as special cases.
[ { "created": "Mon, 30 Sep 2002 09:45:06 GMT", "version": "v1" } ]
2009-11-07
[ [ "Barrabes", "C.", "" ], [ "Hogan", "P. A.", "" ] ]
We present a systematic study of collisions of homogeneous, plane--fronted, impulsive light--like signals which do not interact after head--on collision. For the head--on collision of two such signals, six real parameters are involved, three from each of the incoming signals. We find two necessary conditions to be satisfied by these six parameters for the signals to be non--interacting after collision. We then solve the collision problem in general when these necessary conditions hold. After collision the two signals focus each other at Weyl curvature singularities on each others signal front. Our family of solutions contains some known collision solutions as special cases.
0803.3442
Alexei Zayats
Alexander B. Balakin, Heinz Dehnen, Alexei E. Zayats
Non-minimal pp-wave Einstein-Yang-Mills-Higgs model: color cross-effects induced by curvature
19 pages, accepted to Gen. Rel. Grav
Gen.Rel.Grav.40:2493-2513,2008
10.1007/s10714-008-0634-4
null
gr-qc astro-ph hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Non-minimal interactions in the pp-wave Einstein - Yang - Mills - Higgs (EYMH) model are shown to give rise to color cross-effects analogous to the magneto-electricity in the Maxwell theory. In order to illustrate the significance of these color cross-effects, we reconstruct the effective (associated, color and color-acoustic) metrics for the pp-wave non-minimal seven-parameter EYMH model with parallel gauge and scalar background fields. Then these metrics are used as hints for obtaining explicit exact solutions of the non-minimally extended Yang-Mills and Higgs equations for the test fields propagating in the vacuum interacting with curvature. The influence of the non-minimal coupling on the test particle motion is interpreted in terms of the so-called trapped surfaces, introduced in the Analog Gravity theory.
[ { "created": "Mon, 24 Mar 2008 18:14:58 GMT", "version": "v1" } ]
2008-12-18
[ [ "Balakin", "Alexander B.", "" ], [ "Dehnen", "Heinz", "" ], [ "Zayats", "Alexei E.", "" ] ]
Non-minimal interactions in the pp-wave Einstein - Yang - Mills - Higgs (EYMH) model are shown to give rise to color cross-effects analogous to the magneto-electricity in the Maxwell theory. In order to illustrate the significance of these color cross-effects, we reconstruct the effective (associated, color and color-acoustic) metrics for the pp-wave non-minimal seven-parameter EYMH model with parallel gauge and scalar background fields. Then these metrics are used as hints for obtaining explicit exact solutions of the non-minimally extended Yang-Mills and Higgs equations for the test fields propagating in the vacuum interacting with curvature. The influence of the non-minimal coupling on the test particle motion is interpreted in terms of the so-called trapped surfaces, introduced in the Analog Gravity theory.
gr-qc/0208001
Anzhong Wang
Paulo R.C.T. Pereira and A.Z. Wang
Collapsing and Expanding Cylindrically Symmetric Fields with Ligh-tlike Wave-Fronts in General Relativity
3 figures, prepared in Latex. Inter. J. Mod. Phys. D11, 561-579 (2002)
Int.J.Mod.Phys. D11 (2002) 561-579
10.1142/S0218271802001664
null
gr-qc
null
The dynamics of collapsing and expanding cylindrically symmetric gravitational and matter fields with lightlike wave-fronts is studied in General Relativity, using the Barrabes-Israel method. As an application of the general formulae developed, the collapse of a matter field that satisfies the condition R_{AB}g^{AB} = 0, (A, B = z, phi), in an otherwise flat spacetime background is studied. In particular, it is found that the gravitational collapse of a purely gravitational wave or a null dust fluid cannot be realized in a flat spacetime background. The studies are further specified to the collapse of purely gravitational waves and the general conditions for such collapse are found. It is shown that after the waves arrive at the axis, in general, part of them is reflected to spacelike infinity along the future light cone, and part of it is focused to form spacetime singularities on the symmetry axis. The cases where the collapse does not result in the formation of spacetime singularities are also identified.
[ { "created": "Thu, 1 Aug 2002 19:02:48 GMT", "version": "v1" } ]
2009-11-07
[ [ "Pereira", "Paulo R. C. T.", "" ], [ "Wang", "A. Z.", "" ] ]
The dynamics of collapsing and expanding cylindrically symmetric gravitational and matter fields with lightlike wave-fronts is studied in General Relativity, using the Barrabes-Israel method. As an application of the general formulae developed, the collapse of a matter field that satisfies the condition R_{AB}g^{AB} = 0, (A, B = z, phi), in an otherwise flat spacetime background is studied. In particular, it is found that the gravitational collapse of a purely gravitational wave or a null dust fluid cannot be realized in a flat spacetime background. The studies are further specified to the collapse of purely gravitational waves and the general conditions for such collapse are found. It is shown that after the waves arrive at the axis, in general, part of them is reflected to spacelike infinity along the future light cone, and part of it is focused to form spacetime singularities on the symmetry axis. The cases where the collapse does not result in the formation of spacetime singularities are also identified.
1008.0248
Martin Scholtz
Ji\v{r}\'i Bi\v{c}\'ak and Martin Scholtz and Paul Tod
On asymptotically flat solutions of Einstein's equations periodic in time II. Spacetimes with scalar-field sources
29 pages, published in Class. Quant. Grav. Replaced. Typos corrected, version which appeared in Class. Quant.Grav
Class.Quant.Grav.27:175011,2010
10.1088/0264-9381/27/17/175011
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the work in our earlier article [4] to show that time-periodic, asymptotically-flat solutions of the Einstein equations analytic at scri, whose source is one of a range of scalar-field models, are necessarily stationary. We also show that, for some of these scalar-field sources, in stationary, asymptotically-flat solutions analytic at scri, the scalar field necessarily inherits the symmetry. To prove these results we investigate miscellaneous properties of massless and conformal scalar fields coupled to gravity, in particular Bondi mass and its loss.
[ { "created": "Mon, 2 Aug 2010 08:07:20 GMT", "version": "v1" }, { "created": "Fri, 6 Aug 2010 10:08:48 GMT", "version": "v2" } ]
2011-01-18
[ [ "Bičák", "Jiří", "" ], [ "Scholtz", "Martin", "" ], [ "Tod", "Paul", "" ] ]
We extend the work in our earlier article [4] to show that time-periodic, asymptotically-flat solutions of the Einstein equations analytic at scri, whose source is one of a range of scalar-field models, are necessarily stationary. We also show that, for some of these scalar-field sources, in stationary, asymptotically-flat solutions analytic at scri, the scalar field necessarily inherits the symmetry. To prove these results we investigate miscellaneous properties of massless and conformal scalar fields coupled to gravity, in particular Bondi mass and its loss.
2010.15079
Javlon Rayimbaev Javlon
Javlon Rayimbaev, Ahmadjon Abdujabbarov, Mubasher Jamil, Bobomurat Ahmedov, Wen-Biao Han
Dynamics of test particles around renormalization group improved Schwarzschild black holes
16 pages, 16 figures. arXiv admin note: text overlap with arXiv:2010.12863
Phys. Rev. D 102, 084016 (2020)
10.1103/PhysRevD.102.084016
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we have investigated the dynamics of neutral, electrically charged and magnetized particles around renormalized group improved (RGI) Schwarzschild black hole in the presence of external asymptotically uniform magnetic field. We have analyzed the spacetime structure around RGI black hole by investigating Ricci, the square of Ricci tensor and Kretschmann curvature scalars and shown that only in the case when the parameter $\gamma=0$ the curvature becomes infinite at the center of the black hole, while for non-zero values of $\gamma$ parameter the black hole curvature reflects the properties of regular black hole. Analyzing the innermost stable circular orbits of test neutral particles around RGI black hole and comparing with the results for rotating Kerr black hole we have shown that RGI black hole parameters can mimic the rotation parameter of Kerr black hole upto $a/M \lesssim 0.31$ providing the same ISCO radius. Since according to the astronomical observations of the accretion disks confirm that the astrophysical black holes are rapidly rotating with the spin parameter upto $a/M \sim 0.99$ one may conclude that the effects of parameters of RGI Schwarzschild black hole on the circular orbits of the neutral particles can not mimic the Kerr black hole. Then the Hamilton-Jacobi equation has been used to analyze the charged and magnetized particles motion near the RGI black hole in the presence of the strong interaction between external asymptotically uniform magnetic (electromagnetic) field and magnetized (electrically charged) particle. We have shown that RGI black hole parameters quantitatively change the dynamics of the charged and magnetized particles, in particular ISCO radius of the particles decreases with increasing the parameter $\lambda$, while the increase of the parameter $\gamma$ causes to increase of it.
[ { "created": "Mon, 26 Oct 2020 08:58:33 GMT", "version": "v1" } ]
2020-11-02
[ [ "Rayimbaev", "Javlon", "" ], [ "Abdujabbarov", "Ahmadjon", "" ], [ "Jamil", "Mubasher", "" ], [ "Ahmedov", "Bobomurat", "" ], [ "Han", "Wen-Biao", "" ] ]
In this paper we have investigated the dynamics of neutral, electrically charged and magnetized particles around renormalized group improved (RGI) Schwarzschild black hole in the presence of external asymptotically uniform magnetic field. We have analyzed the spacetime structure around RGI black hole by investigating Ricci, the square of Ricci tensor and Kretschmann curvature scalars and shown that only in the case when the parameter $\gamma=0$ the curvature becomes infinite at the center of the black hole, while for non-zero values of $\gamma$ parameter the black hole curvature reflects the properties of regular black hole. Analyzing the innermost stable circular orbits of test neutral particles around RGI black hole and comparing with the results for rotating Kerr black hole we have shown that RGI black hole parameters can mimic the rotation parameter of Kerr black hole upto $a/M \lesssim 0.31$ providing the same ISCO radius. Since according to the astronomical observations of the accretion disks confirm that the astrophysical black holes are rapidly rotating with the spin parameter upto $a/M \sim 0.99$ one may conclude that the effects of parameters of RGI Schwarzschild black hole on the circular orbits of the neutral particles can not mimic the Kerr black hole. Then the Hamilton-Jacobi equation has been used to analyze the charged and magnetized particles motion near the RGI black hole in the presence of the strong interaction between external asymptotically uniform magnetic (electromagnetic) field and magnetized (electrically charged) particle. We have shown that RGI black hole parameters quantitatively change the dynamics of the charged and magnetized particles, in particular ISCO radius of the particles decreases with increasing the parameter $\lambda$, while the increase of the parameter $\gamma$ causes to increase of it.
2108.08242
Despoina Pazouli
Despoina Pazouli
High-harmonic cosmic strings and gravitational waves
PhD thesis, School of Physics and Astronomy, Faculty of Science, University of Nottingham, October 2020
null
null
null
gr-qc astro-ph.CO hep-th
http://creativecommons.org/licenses/by/4.0/
In this thesis we describe high-harmonic cosmic string loops in a general relativistic context, and study the implications of high-harmonic content for the predicted gravitational wave signal from cosmic string networks. Initially, we introduce the variational principle, spacetime concepts and other mathematical tools that we will need for the calculations in the following chapters. We introduce the FLRW universe and the $\Lambda CDM$ universe. We then describe the Nambu-Goto cosmic string in a curved spacetime, its equations of motion and its energy-momentum tensor. Fixing the spacetime to be flat, and fixing the gauge, we find the motion of the cosmic string and we present and discuss special solutions. Using the odd-harmonic family of cosmic string loops, we calculate the number of cusps per period and the values of the second derivatives of the left- and right-moving harmonic modes at the cusp, and study their dependence on the harmonic order. We then develop a toy model that calculates the stable daughter loops produced from a parent loop using a statistical approach based on a binary tree description of the loop chopping. We also use the toy model to calculate the average number of cusps produced from a system of loops that self intersect over their course of existence. We derive the gravitational waveform emitted from a cusp as observed away from the cusp, in any direction of observation. We then propagate this result in an FLRW spacetime to reach an expression of its amplitude on Earth. Assuming two different cosmic string network models, we implement our above mentioned high-harmonic results to find the amplitude of the signal and the rate at which these signals reach an observer on Earth.
[ { "created": "Wed, 18 Aug 2021 17:02:36 GMT", "version": "v1" } ]
2021-08-19
[ [ "Pazouli", "Despoina", "" ] ]
In this thesis we describe high-harmonic cosmic string loops in a general relativistic context, and study the implications of high-harmonic content for the predicted gravitational wave signal from cosmic string networks. Initially, we introduce the variational principle, spacetime concepts and other mathematical tools that we will need for the calculations in the following chapters. We introduce the FLRW universe and the $\Lambda CDM$ universe. We then describe the Nambu-Goto cosmic string in a curved spacetime, its equations of motion and its energy-momentum tensor. Fixing the spacetime to be flat, and fixing the gauge, we find the motion of the cosmic string and we present and discuss special solutions. Using the odd-harmonic family of cosmic string loops, we calculate the number of cusps per period and the values of the second derivatives of the left- and right-moving harmonic modes at the cusp, and study their dependence on the harmonic order. We then develop a toy model that calculates the stable daughter loops produced from a parent loop using a statistical approach based on a binary tree description of the loop chopping. We also use the toy model to calculate the average number of cusps produced from a system of loops that self intersect over their course of existence. We derive the gravitational waveform emitted from a cusp as observed away from the cusp, in any direction of observation. We then propagate this result in an FLRW spacetime to reach an expression of its amplitude on Earth. Assuming two different cosmic string network models, we implement our above mentioned high-harmonic results to find the amplitude of the signal and the rate at which these signals reach an observer on Earth.
1012.5619
Yurii Ignatyev
Yu.G.Ignatyev, K.Alsmadi
The complete relativistic kinetic model of violation of symmetry in isotopic expanding plasma and production of baryons in hot Universe. I. Exact model
12 pages
Grav.Cosmol.11:1-12,2005
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The complete model of production of baryons in expanding primordial symmetrical hot Universe is constructed in terms of general relativistic kinetic theory
[ { "created": "Mon, 27 Dec 2010 14:41:21 GMT", "version": "v1" } ]
2011-01-28
[ [ "Ignatyev", "Yu. G.", "" ], [ "Alsmadi", "K.", "" ] ]
The complete model of production of baryons in expanding primordial symmetrical hot Universe is constructed in terms of general relativistic kinetic theory
gr-qc/9912023
Alessandro Fabbri
G. Clement and A. Fabbri
The cosmological gravitating $\sigma$ model: solitons and black holes
10 pages, latex
Class.Quant.Grav. 17 (2000) 2537-2546
10.1088/0264-9381/17/13/307
null
gr-qc hep-th
null
We derive and analyze exact static solutions to the gravitating O(3) $\sigma$ model with cosmological constant in (2+1) dimensions. Both signs of the gravitational and cosmological constants are considered. Our solutions include geodesically complete spacetimes, and two classes of black holes.
[ { "created": "Tue, 7 Dec 1999 22:32:53 GMT", "version": "v1" }, { "created": "Wed, 8 Dec 1999 12:06:58 GMT", "version": "v2" } ]
2009-10-31
[ [ "Clement", "G.", "" ], [ "Fabbri", "A.", "" ] ]
We derive and analyze exact static solutions to the gravitating O(3) $\sigma$ model with cosmological constant in (2+1) dimensions. Both signs of the gravitational and cosmological constants are considered. Our solutions include geodesically complete spacetimes, and two classes of black holes.
gr-qc/0406116
Manuel Tiglio
Luis Lehner, David Neilsen, Oscar Reula, and Manuel Tiglio
The discrete energy method in numerical relativity: Towards long-term stability
18 pages, 22 figures
Class.Quant.Grav. 21 (2004) 5819-5848
10.1088/0264-9381/21/24/009
LSU-REL-062804
gr-qc
null
The energy method can be used to identify well-posed initial boundary value problems for quasi-linear, symmetric hyperbolic partial differential equations with maximally dissipative boundary conditions. A similar analysis of the discrete system can be used to construct stable finite difference equations for these problems at the linear level. In this paper we apply these techniques to some test problems commonly used in numerical relativity and observe that while we obtain convergent schemes, fast growing modes, or ``artificial instabilities,'' contaminate the solution. We find that these growing modes can partially arise from the lack of a Leibnitz rule for discrete derivatives and discuss ways to limit this spurious growth.
[ { "created": "Tue, 29 Jun 2004 00:02:38 GMT", "version": "v1" } ]
2009-11-10
[ [ "Lehner", "Luis", "" ], [ "Neilsen", "David", "" ], [ "Reula", "Oscar", "" ], [ "Tiglio", "Manuel", "" ] ]
The energy method can be used to identify well-posed initial boundary value problems for quasi-linear, symmetric hyperbolic partial differential equations with maximally dissipative boundary conditions. A similar analysis of the discrete system can be used to construct stable finite difference equations for these problems at the linear level. In this paper we apply these techniques to some test problems commonly used in numerical relativity and observe that while we obtain convergent schemes, fast growing modes, or ``artificial instabilities,'' contaminate the solution. We find that these growing modes can partially arise from the lack of a Leibnitz rule for discrete derivatives and discuss ways to limit this spurious growth.
1809.09554
Tatyana P. Shestakova
T. P. Shestakova
Is the Copenhagen interpretation inapplicable to Quantum Cosmology?
23 pages, no figures, the version of the paper that has been published in the journal Universe
Universe 6 (2020) 128
10.3390/universe6090128
null
gr-qc physics.hist-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is generally accepted that the Copenhagen interpretation is inapplicable to quantum cosmology, by contrast with the many worlds interpretation. I shall demonstrate that the two basic principles of the Copenhagen interpretation, the principle of wholeness and the principle of complementarity, do make sense in quantum gravity, since we can judge about quantum gravitational processes in the Very Early Universe by their vestiges in our macroscopic Universe. I shall present the extended phase space approach to quantum gravity and show that it can be interpreted in the spirit of the Everett's `relative states' formulation, while there is no contradiction between the `relative states' formulation and the mentioned basic principles of the Copenhagen interpretation.
[ { "created": "Tue, 25 Sep 2018 15:36:40 GMT", "version": "v1" }, { "created": "Mon, 24 Aug 2020 13:14:51 GMT", "version": "v2" } ]
2020-08-25
[ [ "Shestakova", "T. P.", "" ] ]
It is generally accepted that the Copenhagen interpretation is inapplicable to quantum cosmology, by contrast with the many worlds interpretation. I shall demonstrate that the two basic principles of the Copenhagen interpretation, the principle of wholeness and the principle of complementarity, do make sense in quantum gravity, since we can judge about quantum gravitational processes in the Very Early Universe by their vestiges in our macroscopic Universe. I shall present the extended phase space approach to quantum gravity and show that it can be interpreted in the spirit of the Everett's `relative states' formulation, while there is no contradiction between the `relative states' formulation and the mentioned basic principles of the Copenhagen interpretation.
1504.04173
Behnam Pourhassan
B. Pourhassan
Unified universe history through phantom extended Chaplygin gas
25 pages, 16 figures
Canadian Journal of Physics 94 (2016) 659
10.1139/cjp-2016-0154
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the universe evolution from inflation to late-time acceleration in a unified way, using a two-component fluid constituted from extended Chaplygin gas alongside a phantom scalar field. We extract solutions for the various cosmological eras, focusing on the behavior of the scale factor, the various density parameters and the equation-of-state parameter. Furthermore, we extract and discuss bouncing solutions. Finally, we examine the perturbations of the model, ensuring about their stability and extracting the predictions for the tensor-to-scalar ratio.
[ { "created": "Wed, 15 Apr 2015 19:49:58 GMT", "version": "v1" } ]
2016-07-15
[ [ "Pourhassan", "B.", "" ] ]
We investigate the universe evolution from inflation to late-time acceleration in a unified way, using a two-component fluid constituted from extended Chaplygin gas alongside a phantom scalar field. We extract solutions for the various cosmological eras, focusing on the behavior of the scale factor, the various density parameters and the equation-of-state parameter. Furthermore, we extract and discuss bouncing solutions. Finally, we examine the perturbations of the model, ensuring about their stability and extracting the predictions for the tensor-to-scalar ratio.
2105.05050
Adam Zenon Kaczmarek
Adam Zenon Kaczmarek and Dominik Szcz\k{e}\'sniak
Cosmology in the mimetic higher-curvature $f(R, R_{\mu\nu}R^{\mu\nu})$ gravity
12 pages, 2 figures
null
10.1038/s41598-021-97907-y
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
In the framework of the mimetic approach, we study the $f(R,R_{\mu\nu}R^{\mu\nu})$ gravity with the Lagrange multiplier constraint and the scalar potential. We introduce field equations for the discussed theory and overview their properties. By using the general reconstruction scheme we obtain the power law cosmology model for the $f(R,R_{\mu\nu}R^{\mu\nu})=R+d(R_{\mu\nu}R^{\mu\nu})^p$ case as well as the model that describes symmetric bounce. Moreover, we reconstruct model, unifying both matter dominated and accelerated phases, where ordinary matter is neglected. Using inverted reconstruction scheme we recover specific $f(R,R_{\mu\nu}R^{\mu\nu})$ function which give rise to the de-Sitter evolution. Finally, by employing the perfect fluid approach, we demonstrate that this model can realize inflation consistent with the bounds coming from the BICEP2/Keck array and the Planck data. Thus, it is suggested that the introduced extension of the mimetic regime may describe any given cosmological model.
[ { "created": "Sun, 9 May 2021 10:29:42 GMT", "version": "v1" } ]
2021-11-18
[ [ "Kaczmarek", "Adam Zenon", "" ], [ "Szczęśniak", "Dominik", "" ] ]
In the framework of the mimetic approach, we study the $f(R,R_{\mu\nu}R^{\mu\nu})$ gravity with the Lagrange multiplier constraint and the scalar potential. We introduce field equations for the discussed theory and overview their properties. By using the general reconstruction scheme we obtain the power law cosmology model for the $f(R,R_{\mu\nu}R^{\mu\nu})=R+d(R_{\mu\nu}R^{\mu\nu})^p$ case as well as the model that describes symmetric bounce. Moreover, we reconstruct model, unifying both matter dominated and accelerated phases, where ordinary matter is neglected. Using inverted reconstruction scheme we recover specific $f(R,R_{\mu\nu}R^{\mu\nu})$ function which give rise to the de-Sitter evolution. Finally, by employing the perfect fluid approach, we demonstrate that this model can realize inflation consistent with the bounds coming from the BICEP2/Keck array and the Planck data. Thus, it is suggested that the introduced extension of the mimetic regime may describe any given cosmological model.
gr-qc/0412131
Plamen Fiziev
Plamen Fiziev
The Gravitational Field of Massive Non-Charged Point Source in General Relativity
12 pages, latex file, no figures
in Proceedings of the Conference Contemporary Aspects of Astronomy, Theoretical and Gravitational Physics, May 20-22, 2004, Sofia, Bulgaria
null
SU-TH-22-04
gr-qc
null
Utilizing various gauges of the radial coordinate we give a description of static spherically symmetric space-times with point singularity at the center and vacuum outside the singularity. We show that in general relativity (GR) there exist a two-parameters family of such solutions to the Einstein equations which are physically distinguishable but only some of them describe the gravitational field of a single massive point particle with nonzero bare mass $M_0$. In particular, the widespread Hilbert's form of Schwarzschild solution, which depends only on the Keplerian mass $M<M_0$, does not solve the Einstein equations with a massive point particle's stress-energy tensor as a source. Novel normal coordinates for the field and a new physical class of gauges are proposed, in this way achieving a correct description of a point mass source in GR. We also introduce a gravitational mass defect of a point particle and determine the dependence of the solutions on this mass defect. The result can be described as a change of the Newton potential $\phi_{{}_N}=-G_{{}_N}M/r$ to a modified one: $\phi_{{}_G}=-G_{{}_N}M/ (r+G_{{}_N} M/c^2\ln{{M_0}\over M})$ and a corresponding modification of the four-interval. In addition we give invariant characteristics of the physically and geometrically different classes of spherically symmetric static space-times created by one point mass. These space-times are analytic manifolds with a definite singularity at the place of the matter particle.
[ { "created": "Thu, 30 Dec 2004 12:22:45 GMT", "version": "v1" } ]
2007-05-23
[ [ "Fiziev", "Plamen", "" ] ]
Utilizing various gauges of the radial coordinate we give a description of static spherically symmetric space-times with point singularity at the center and vacuum outside the singularity. We show that in general relativity (GR) there exist a two-parameters family of such solutions to the Einstein equations which are physically distinguishable but only some of them describe the gravitational field of a single massive point particle with nonzero bare mass $M_0$. In particular, the widespread Hilbert's form of Schwarzschild solution, which depends only on the Keplerian mass $M<M_0$, does not solve the Einstein equations with a massive point particle's stress-energy tensor as a source. Novel normal coordinates for the field and a new physical class of gauges are proposed, in this way achieving a correct description of a point mass source in GR. We also introduce a gravitational mass defect of a point particle and determine the dependence of the solutions on this mass defect. The result can be described as a change of the Newton potential $\phi_{{}_N}=-G_{{}_N}M/r$ to a modified one: $\phi_{{}_G}=-G_{{}_N}M/ (r+G_{{}_N} M/c^2\ln{{M_0}\over M})$ and a corresponding modification of the four-interval. In addition we give invariant characteristics of the physically and geometrically different classes of spherically symmetric static space-times created by one point mass. These space-times are analytic manifolds with a definite singularity at the place of the matter particle.
2207.04720
Alejandro Garc\'ia-Quismondo
Alejandro Garc\'ia-Quismondo and Guillermo A. Mena Marug\'an
Two-time alternative to the Ashtekar-Olmedo-Singh black hole interior
21 pages and 5 figures
Phys. Rev. D 106, 023532 (2022)
10.1103/PhysRevD.106.023532
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the viability of a recently proposed generalization of the Ashtekar-Olmedo-Singh spacetime for the effective description of the interior region of a Schwarzschild black hole within the framework of loop quantum cosmology. The approach is based on a choice of polymerization parameters that is more general than the ones previously considered in the literature and that results in the natural appearance of two times to describe the solutions. If one is interested in examining the physics derived from this model, it is fundamental to ensure that one can attain a well-defined effective geometry in the whole region under consideration, in particular as regards the redundancy of the two times, which one needs to express in terms of a single time coordinate. In order to determine whether this requirement is met, we analyze the definition of these times and their relation. We show that one can reach an acceptable interior spacetime geometry by exploiting the freedom to define the origins of the two times independently.
[ { "created": "Mon, 11 Jul 2022 08:59:50 GMT", "version": "v1" } ]
2022-09-07
[ [ "García-Quismondo", "Alejandro", "" ], [ "Marugán", "Guillermo A. Mena", "" ] ]
We investigate the viability of a recently proposed generalization of the Ashtekar-Olmedo-Singh spacetime for the effective description of the interior region of a Schwarzschild black hole within the framework of loop quantum cosmology. The approach is based on a choice of polymerization parameters that is more general than the ones previously considered in the literature and that results in the natural appearance of two times to describe the solutions. If one is interested in examining the physics derived from this model, it is fundamental to ensure that one can attain a well-defined effective geometry in the whole region under consideration, in particular as regards the redundancy of the two times, which one needs to express in terms of a single time coordinate. In order to determine whether this requirement is met, we analyze the definition of these times and their relation. We show that one can reach an acceptable interior spacetime geometry by exploiting the freedom to define the origins of the two times independently.
1501.01641
Olivier Sarbach
Eliana Chaverra and Olivier Sarbach
Radial accretion flows on static spherically symmetric black holes
25 pages, 5 figures. Typos corrected, additional references, new figure showing accretion flow in deformed Schwarzschild black hole. To appear in Classical and Quantum Gravity
null
10.1088/0264-9381/32/15/155006
null
gr-qc astro-ph.SR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the steady radial accretion of matter into a nonrotating black hole. Neglecting the self-gravity of the accreting matter, we consider a rather general class of static, spherically symmetric and asymptotically flat background spacetimes with a regular horizon. In addition to the Schwarzschild metric, this class contains certain deformation of it which could arise in alternative gravity theories or from solutions of the classical Einstein equations in the presence of external matter fields. Modeling the ambient matter surrounding the black hole by a relativistic perfect fluid, we reformulate the accretion problem as a dynamical system, and under rather general assumptions on the fluid equation of state, we determine the local and global qualitative behavior of its phase flow. Based on our analysis and generalizing previous work by Michel, we prove that for any given positive particle density number at infinity, there exists a unique radial, steady-state accretion flow which is regular at the horizon. We determine the physical parameters of the flow, including its accretion and compression rates, and discuss their dependency on the background metric.
[ { "created": "Wed, 7 Jan 2015 21:00:33 GMT", "version": "v1" }, { "created": "Tue, 9 Jun 2015 17:45:07 GMT", "version": "v2" } ]
2015-08-06
[ [ "Chaverra", "Eliana", "" ], [ "Sarbach", "Olivier", "" ] ]
We analyze the steady radial accretion of matter into a nonrotating black hole. Neglecting the self-gravity of the accreting matter, we consider a rather general class of static, spherically symmetric and asymptotically flat background spacetimes with a regular horizon. In addition to the Schwarzschild metric, this class contains certain deformation of it which could arise in alternative gravity theories or from solutions of the classical Einstein equations in the presence of external matter fields. Modeling the ambient matter surrounding the black hole by a relativistic perfect fluid, we reformulate the accretion problem as a dynamical system, and under rather general assumptions on the fluid equation of state, we determine the local and global qualitative behavior of its phase flow. Based on our analysis and generalizing previous work by Michel, we prove that for any given positive particle density number at infinity, there exists a unique radial, steady-state accretion flow which is regular at the horizon. We determine the physical parameters of the flow, including its accretion and compression rates, and discuss their dependency on the background metric.
2304.10623
Adnan Malik
Zoya Asghar, M. Farasat Shamir, Ammara Usman, Adnan Malik
Study of Embedded Class-I Fluid Spheres in $f(R,T)$ Gravity with Karmarkar Condition
12 pages, 10 figures, Accepted for publication in Chinese Journal of Physics
null
10.1016/j.cjph.2023.04.009
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
In this article, we explore some emerging properties of the stellar objects in the frame of the $f(R,T)$ gravity by employing the well-known Karmarkar condition, where $R$ and $T$ represent Ricci scalar and trace of energy momentum tensor respectively. It is worthy to highlight here that we assume the exponential type model of $f(R,T)$ theory of gravity $f(R,T)=R+\alpha(e^{-\beta R}-1)+\gamma T$ along with the matter Lagrangian $\mathcal{L}_{m}=-\frac{1}{3}(p_{r}+2 p_{t})$ to classify the complete set of modified field equations. We demonstrate the embedded class-I technique by using the static spherically symmetric line element along with anisotropic fluid matter distribution. Further, to achieve our goal, we consider a specific expression of metric potential $g_{rr}$, already presented in literature, and proceed by using the Karmarkar condition to obtain the second metric potential. In particular, we use four different compact stars, namely $LMC~X-4,$ $EXO~1785-248,$ $Cen~X-3$ and $4U~1820-30$ and compute the corresponding values of the unknown parameters appearing in metric potentials. Moreover, we conduct various physical evolutions such as graphical nature of energy density and pressure progression, energy constraints, mass function, adiabatic index, stability and equilibrium conditions to ensure the viability and consistency of our proposed model. Our analysis indicates that the obtained anisotropic outcomes are physically acceptable with the finest degree of accuracy.
[ { "created": "Wed, 19 Apr 2023 14:09:47 GMT", "version": "v1" } ]
2023-05-24
[ [ "Asghar", "Zoya", "" ], [ "Shamir", "M. Farasat", "" ], [ "Usman", "Ammara", "" ], [ "Malik", "Adnan", "" ] ]
In this article, we explore some emerging properties of the stellar objects in the frame of the $f(R,T)$ gravity by employing the well-known Karmarkar condition, where $R$ and $T$ represent Ricci scalar and trace of energy momentum tensor respectively. It is worthy to highlight here that we assume the exponential type model of $f(R,T)$ theory of gravity $f(R,T)=R+\alpha(e^{-\beta R}-1)+\gamma T$ along with the matter Lagrangian $\mathcal{L}_{m}=-\frac{1}{3}(p_{r}+2 p_{t})$ to classify the complete set of modified field equations. We demonstrate the embedded class-I technique by using the static spherically symmetric line element along with anisotropic fluid matter distribution. Further, to achieve our goal, we consider a specific expression of metric potential $g_{rr}$, already presented in literature, and proceed by using the Karmarkar condition to obtain the second metric potential. In particular, we use four different compact stars, namely $LMC~X-4,$ $EXO~1785-248,$ $Cen~X-3$ and $4U~1820-30$ and compute the corresponding values of the unknown parameters appearing in metric potentials. Moreover, we conduct various physical evolutions such as graphical nature of energy density and pressure progression, energy constraints, mass function, adiabatic index, stability and equilibrium conditions to ensure the viability and consistency of our proposed model. Our analysis indicates that the obtained anisotropic outcomes are physically acceptable with the finest degree of accuracy.
gr-qc/9911112
Abel Camacho Quintana
Abel Camacho Quintana (Astrophysikalisches Institut Potsdam)
Flavor-oscillation clocks, continuous quantum measurements and a violation of Einstein equivalence principle
16 pages, accepted in Mod. Phys. Letts.A
Mod.Phys.Lett. A14 (1999) 2545-2556
10.1142/S0217732399002662
null
gr-qc quant-ph
null
The relation between Einstein equivalence principle and a continuous quantum measurement is analyzed in the context of the recently proposed flavor-oscillation clocks, an idea pioneered by Ahluwalia and Burgard (Gen. Rel Grav. Errata 29, 681 (1997)). We will calculate the measurement outputs if a flavor-oscillation clock, which is immersed in a gravitational field, is subject to a continuous quantum measurement. Afterwards, resorting to the weak equivalence principle, we obtain the corresponding quantities in a freely falling reference frame. Finally, comparing this last result with the measurement outputs that would appear in a Minkowskian spacetime it will be found that they do not coincide, in other words, we have a violation of Einstein equivalence principle. This violation appears in two different forms, namely: (i) the oscillation frequency in a freely falling reference frame does not match with the case predicted by general relativity, a feature previously obtained by Ahluwalia; (ii) the probability distribution of the measurement outputs, obtained by an observer in a freely falling reference frame, does not coincide with the results that would appear in the case of a Minkowskian spacetime.
[ { "created": "Sun, 28 Nov 1999 15:31:27 GMT", "version": "v1" } ]
2009-10-31
[ [ "Quintana", "Abel Camacho", "", "Astrophysikalisches Institut Potsdam" ] ]
The relation between Einstein equivalence principle and a continuous quantum measurement is analyzed in the context of the recently proposed flavor-oscillation clocks, an idea pioneered by Ahluwalia and Burgard (Gen. Rel Grav. Errata 29, 681 (1997)). We will calculate the measurement outputs if a flavor-oscillation clock, which is immersed in a gravitational field, is subject to a continuous quantum measurement. Afterwards, resorting to the weak equivalence principle, we obtain the corresponding quantities in a freely falling reference frame. Finally, comparing this last result with the measurement outputs that would appear in a Minkowskian spacetime it will be found that they do not coincide, in other words, we have a violation of Einstein equivalence principle. This violation appears in two different forms, namely: (i) the oscillation frequency in a freely falling reference frame does not match with the case predicted by general relativity, a feature previously obtained by Ahluwalia; (ii) the probability distribution of the measurement outputs, obtained by an observer in a freely falling reference frame, does not coincide with the results that would appear in the case of a Minkowskian spacetime.
1911.09892
Patrick Peter
Przemyslaw Malkiewicz, Patrick Peter, S. D. P. Vitenti
Quantum empty Bianchi I spacetime with internal time
16 pages, 13 figures, matches version to appear in Phys. Rev. D
Phys. Rev. D 101, 046012 (2020)
10.1103/PhysRevD.101.046012
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the question of time in a Bianchi I quantum cosmology in the framework of singularity avoidance. We show that time parameters fall into two distinct classes, that are such that the time development of the wave function either always leads to the appearance of a singularity (fast-gauge time) or that always prevents it from occurring (slow-gauge time). Furthermore, we find that, in the latter case, there exists an asymptotic regime, independent of the clock choice. This may point to a possible solution of the clock issue in quantum cosmology if there exists a suitable class of clocks all yielding identical relevant physical consequences.
[ { "created": "Fri, 22 Nov 2019 07:12:28 GMT", "version": "v1" }, { "created": "Mon, 20 Jan 2020 09:57:52 GMT", "version": "v2" }, { "created": "Fri, 7 Feb 2020 14:02:19 GMT", "version": "v3" } ]
2020-02-18
[ [ "Malkiewicz", "Przemyslaw", "" ], [ "Peter", "Patrick", "" ], [ "Vitenti", "S. D. P.", "" ] ]
We discuss the question of time in a Bianchi I quantum cosmology in the framework of singularity avoidance. We show that time parameters fall into two distinct classes, that are such that the time development of the wave function either always leads to the appearance of a singularity (fast-gauge time) or that always prevents it from occurring (slow-gauge time). Furthermore, we find that, in the latter case, there exists an asymptotic regime, independent of the clock choice. This may point to a possible solution of the clock issue in quantum cosmology if there exists a suitable class of clocks all yielding identical relevant physical consequences.
gr-qc/0306125
Daniel A. Shaddock
Daniel A. Shaddock
Operating LISA as a Sagnac interferometer
8 pages, 2 figures
Phys.Rev. D69 (2004) 022001
10.1103/PhysRevD.69.022001
null
gr-qc
null
A phase-locking configuration for LISA is proposed that provides a significantly simpler mode of operation. The scheme provides one Sagnac signal readout inherently insensitive to laser frequency noise and optical bench motion for a non-rotating LISA array. This Sagnac output is also insensitive to clock noise, requires no time shifting of data, nor absolute arm length knowledge. As all measurements are made at one spacecraft, neither clock synchronization nor exchange of phase information between spacecraft is required. The phase-locking configuration provides these advantages for only one Sagnac variable yet retains compatibility with the baseline approach for obtaining the other TDI variables. The orbital motion of the LISA constellation is shown to produce a 14 km path length difference between the counter-propagating beams in the Sagnac interferometer. With this length difference a laser frequency noise spectral density of 1 Hz/$\sqrt{\rm Hz}$ would consume the entire optical path noise budget of the Sagnac variables. A significant improvement of laser frequency stability (currently at 30 Hz/$\sqrt{\rm Hz}$) would be needed for full-sensitivity LISA operation in the Sagnac mode. Alternatively, an additional level of time-delay processing could be applied to remove the laser frequency noise. The new time-delayed combinations of the phase measurements are presented.
[ { "created": "Sun, 29 Jun 2003 18:28:42 GMT", "version": "v1" } ]
2009-11-10
[ [ "Shaddock", "Daniel A.", "" ] ]
A phase-locking configuration for LISA is proposed that provides a significantly simpler mode of operation. The scheme provides one Sagnac signal readout inherently insensitive to laser frequency noise and optical bench motion for a non-rotating LISA array. This Sagnac output is also insensitive to clock noise, requires no time shifting of data, nor absolute arm length knowledge. As all measurements are made at one spacecraft, neither clock synchronization nor exchange of phase information between spacecraft is required. The phase-locking configuration provides these advantages for only one Sagnac variable yet retains compatibility with the baseline approach for obtaining the other TDI variables. The orbital motion of the LISA constellation is shown to produce a 14 km path length difference between the counter-propagating beams in the Sagnac interferometer. With this length difference a laser frequency noise spectral density of 1 Hz/$\sqrt{\rm Hz}$ would consume the entire optical path noise budget of the Sagnac variables. A significant improvement of laser frequency stability (currently at 30 Hz/$\sqrt{\rm Hz}$) would be needed for full-sensitivity LISA operation in the Sagnac mode. Alternatively, an additional level of time-delay processing could be applied to remove the laser frequency noise. The new time-delayed combinations of the phase measurements are presented.
1711.07259
Mariana Penna-Lima Vitenti
M.E.S. Alves, F.C. Carvalho, J.C.N. de Araujo, M. Penna-Lima, S.D.P. Vitenti
Cosmological constant constraints from observation-derived energy condition bounds and their application to bimetric massive gravity
11 pages, 4 figures, 1 table
Eur. Phys. J. C (2018) 78: 710
10.1140/epjc/s10052-018-6190-5
null
gr-qc astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including different theories of gravity, with observational data. In this context, we use the ECs to probe any alternative theory whose extra term acts as a cosmological constant. For this purpose, we apply a model-independent approach to reconstruct the recent expansion of the universe. Using Type Ia supernova, baryon acoustic oscillations and cosmic-chronometer data, we perform a Markov Chain Monte Carlo analysis to put constraints on the effective cosmological constant $\Omega^0_{\rm eff}$. By imposing that the cosmological constant is the only component that possibly violates the ECs, we derive lower and upper bounds for its value. For instance, we obtain that $0.59 < \Omega^0_{\rm eff} < 0.91$ and $0.40 < \Omega^0_{\rm eff} < 0.93$ within, respectively, $1\sigma$ and $3\sigma$ confidence levels. In addition, about 30\% of the posterior distribution is incompatible with a cosmological constant, showing that this method can potentially rule it out as a mechanism for the accelerated expansion. We also study the consequence of these constraints for two particular formulations of the bimetric massive gravity. Namely, we consider the Visser's theory and the Hassan and Roses's massive gravity by choosing a background metric such that both theories mimic General Relativity with a cosmological constant. Using the $\Omega^0_{\rm eff}$ observational bounds along with the upper bounds on the graviton mass we obtain constraints on the parameter spaces of both theories.
[ { "created": "Mon, 20 Nov 2017 11:30:24 GMT", "version": "v1" } ]
2018-09-17
[ [ "Alves", "M. E. S.", "" ], [ "Carvalho", "F. C.", "" ], [ "de Araujo", "J. C. N.", "" ], [ "Penna-Lima", "M.", "" ], [ "Vitenti", "S. D. P.", "" ] ]
Among the various possibilities to probe the theory behind the recent accelerated expansion of the universe, the energy conditions (ECs) are of particular interest, since it is possible to confront and constrain the many models, including different theories of gravity, with observational data. In this context, we use the ECs to probe any alternative theory whose extra term acts as a cosmological constant. For this purpose, we apply a model-independent approach to reconstruct the recent expansion of the universe. Using Type Ia supernova, baryon acoustic oscillations and cosmic-chronometer data, we perform a Markov Chain Monte Carlo analysis to put constraints on the effective cosmological constant $\Omega^0_{\rm eff}$. By imposing that the cosmological constant is the only component that possibly violates the ECs, we derive lower and upper bounds for its value. For instance, we obtain that $0.59 < \Omega^0_{\rm eff} < 0.91$ and $0.40 < \Omega^0_{\rm eff} < 0.93$ within, respectively, $1\sigma$ and $3\sigma$ confidence levels. In addition, about 30\% of the posterior distribution is incompatible with a cosmological constant, showing that this method can potentially rule it out as a mechanism for the accelerated expansion. We also study the consequence of these constraints for two particular formulations of the bimetric massive gravity. Namely, we consider the Visser's theory and the Hassan and Roses's massive gravity by choosing a background metric such that both theories mimic General Relativity with a cosmological constant. Using the $\Omega^0_{\rm eff}$ observational bounds along with the upper bounds on the graviton mass we obtain constraints on the parameter spaces of both theories.
2105.01716
Muhammed Saleem C
M. Saleem, Javed Rana, V. Gayathri, Aditya Vijaykumar, Srashti Goyal, Surabhi Sachdev, Jishnu Suresh, S. Sudhagar, Arunava Mukherjee, Gurudatt Gaur, Bangalore Sathyaprakash, Archana Pai, Rana X Adhikari, P. Ajith, Sukanta Bose
The Science Case for LIGO-India
29 pages, 8 figures
Class. Quantum Grav. 39 025004 (2022)
10.1088/1361-6382/ac3b99
null
gr-qc astro-ph.HE
http://creativecommons.org/publicdomain/zero/1.0/
The global network of gravitational-wave detectors has completed three observing runs with $\sim 50$ detections of merging compact binaries. A third LIGO detector, with comparable astrophysical reach, is to be built in India (LIGO-Aundha) and expected to be operational during the latter part of this decade. Multiple detectors operating at different parts of the globe will provide several pairs of interferometers with longer baselines and an increased network SNR. This will improve the sky localisation of GW events. Multiple detectors simultaneously in operation will also increase the baseline duty factor, thereby, leading to an improvement in the detection rates and, hence, the completeness of surveys. In this paper, we quantify the improvements due to the expansion of the LIGO Global Network (LGN) in the precision with which source properties will be measured. We also present examples of how this expansion will give a boost to tests of fundamental physics.
[ { "created": "Tue, 4 May 2021 19:15:26 GMT", "version": "v1" }, { "created": "Fri, 31 Dec 2021 19:28:34 GMT", "version": "v2" } ]
2022-01-04
[ [ "Saleem", "M.", "" ], [ "Rana", "Javed", "" ], [ "Gayathri", "V.", "" ], [ "Vijaykumar", "Aditya", "" ], [ "Goyal", "Srashti", "" ], [ "Sachdev", "Surabhi", "" ], [ "Suresh", "Jishnu", "" ], [ "Sudhagar", "S.", "" ], [ "Mukherjee", "Arunava", "" ], [ "Gaur", "Gurudatt", "" ], [ "Sathyaprakash", "Bangalore", "" ], [ "Pai", "Archana", "" ], [ "Adhikari", "Rana X", "" ], [ "Ajith", "P.", "" ], [ "Bose", "Sukanta", "" ] ]
The global network of gravitational-wave detectors has completed three observing runs with $\sim 50$ detections of merging compact binaries. A third LIGO detector, with comparable astrophysical reach, is to be built in India (LIGO-Aundha) and expected to be operational during the latter part of this decade. Multiple detectors operating at different parts of the globe will provide several pairs of interferometers with longer baselines and an increased network SNR. This will improve the sky localisation of GW events. Multiple detectors simultaneously in operation will also increase the baseline duty factor, thereby, leading to an improvement in the detection rates and, hence, the completeness of surveys. In this paper, we quantify the improvements due to the expansion of the LIGO Global Network (LGN) in the precision with which source properties will be measured. We also present examples of how this expansion will give a boost to tests of fundamental physics.
0802.1972
Ion I. Cot{\ba}escu
Ion I. Cotaescu, Cosmin Crucean, Adrian Pop
The quantum theory of scalar fields on the de Sitter expanding universe
16 pages, no figures
Int.J.Mod.Phys.A23:2563-2577,2008
10.1142/S0217751X08040494
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
New quantum modes of the free scalar field are derived in a special time-evolution picture that may be introduced in moving charts of de Sitter backgrounds. The wave functions of these new modes are solutions of the Klein-Gordon equation and energy eigenfunctions, defining the energy basis. This completes the scalar quantum mechanics where the momentum basis is well-known from long time. In this enlarged framework the quantization of the scalar field can be done in canonical way obtaining the principal conserved one-particle operators and the Green functions.
[ { "created": "Thu, 14 Feb 2008 08:11:20 GMT", "version": "v1" } ]
2008-11-26
[ [ "Cotaescu", "Ion I.", "" ], [ "Crucean", "Cosmin", "" ], [ "Pop", "Adrian", "" ] ]
New quantum modes of the free scalar field are derived in a special time-evolution picture that may be introduced in moving charts of de Sitter backgrounds. The wave functions of these new modes are solutions of the Klein-Gordon equation and energy eigenfunctions, defining the energy basis. This completes the scalar quantum mechanics where the momentum basis is well-known from long time. In this enlarged framework the quantization of the scalar field can be done in canonical way obtaining the principal conserved one-particle operators and the Green functions.
2405.03431
David Fajman
David Fajman, Maciej Maliborski, Maximilian Ofner, Todd Oliynyk, Zoe Wyatt
Phase transition between shock formation and stability in cosmological fluids
6 pages, 3 figures
null
null
null
gr-qc math-ph math.MP
http://creativecommons.org/licenses/by/4.0/
We demonstrate a novel phase transition from stable to unstable fluid behaviour for fluid-filled cosmological spacetimes undergoing decelerated expansion. This transition occurs when the fluid speed of sound $c_S$ exceeds a critical value relative to the expansion rate $a(t) = t^\alpha$ of spacetime. We present an explicit relationship between $\alpha$ and $c_S$ , which subdivides the $(\alpha,c_S)$-parameter space into two regions. Using rigorous techniques, we establish stability of quiet fluid solutions in the first stable region. Numerical experiments reveal that the complement of the stable region consists of unstable solutions, implying sharpness of our stability result. We provide a definitive analytical bound and high-precision numerical evidence for the exact location of the critical line separating the stable from the unstable region.
[ { "created": "Mon, 6 May 2024 12:53:02 GMT", "version": "v1" } ]
2024-05-07
[ [ "Fajman", "David", "" ], [ "Maliborski", "Maciej", "" ], [ "Ofner", "Maximilian", "" ], [ "Oliynyk", "Todd", "" ], [ "Wyatt", "Zoe", "" ] ]
We demonstrate a novel phase transition from stable to unstable fluid behaviour for fluid-filled cosmological spacetimes undergoing decelerated expansion. This transition occurs when the fluid speed of sound $c_S$ exceeds a critical value relative to the expansion rate $a(t) = t^\alpha$ of spacetime. We present an explicit relationship between $\alpha$ and $c_S$ , which subdivides the $(\alpha,c_S)$-parameter space into two regions. Using rigorous techniques, we establish stability of quiet fluid solutions in the first stable region. Numerical experiments reveal that the complement of the stable region consists of unstable solutions, implying sharpness of our stability result. We provide a definitive analytical bound and high-precision numerical evidence for the exact location of the critical line separating the stable from the unstable region.
1504.06321
Cristian Martinez
Cristian Erices and Cristian Martinez
Stationary cylindrically symmetric spacetimes with a massless scalar field and a non-positive cosmological constant
7 pages
Phys. Rev. D 92, 044051 (2015)
10.1103/PhysRevD.92.044051
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The general stationary cylindrically symmetric solution of Einstein-massless scalar field system with a non-positive cosmological constant is presented. It is shown that the general solution is characterized by four integration constants. Two of these essential parameters have a local meaning and characterize the gravitational field strength. The other two have a topological origin, as they define an improper coordinate transformation that provides the stationary solution from the static one. The Petrov scheme is considered to explore the effects of the scalar field on the algebraic classification of the solutions. In general, these spacetimes are of type I. However, the presence of the scalar field allows us to find a non-vacuum type O solution and a wider family of type D spacetimes, in comparison with the vacuum case. The mass and angular momentum of the solution are computed using the Regge-Teitelboim method in the case of a negative cosmological constant. In absence of a cosmological constant, the curvature singularities in the vacuum solutions can be removed by including a phantom scalar field, yielding non-trivial locally homogeneous spacetimes. These spacetimes are of particular interest, as they have all their curvature invariants constant.
[ { "created": "Thu, 23 Apr 2015 20:00:13 GMT", "version": "v1" } ]
2015-09-02
[ [ "Erices", "Cristian", "" ], [ "Martinez", "Cristian", "" ] ]
The general stationary cylindrically symmetric solution of Einstein-massless scalar field system with a non-positive cosmological constant is presented. It is shown that the general solution is characterized by four integration constants. Two of these essential parameters have a local meaning and characterize the gravitational field strength. The other two have a topological origin, as they define an improper coordinate transformation that provides the stationary solution from the static one. The Petrov scheme is considered to explore the effects of the scalar field on the algebraic classification of the solutions. In general, these spacetimes are of type I. However, the presence of the scalar field allows us to find a non-vacuum type O solution and a wider family of type D spacetimes, in comparison with the vacuum case. The mass and angular momentum of the solution are computed using the Regge-Teitelboim method in the case of a negative cosmological constant. In absence of a cosmological constant, the curvature singularities in the vacuum solutions can be removed by including a phantom scalar field, yielding non-trivial locally homogeneous spacetimes. These spacetimes are of particular interest, as they have all their curvature invariants constant.
1910.03546
Vasilis Oikonomou
Shin'ichi Nojiri, S.D. Odintsov, V.K. Oikonomou, Tanmoy Paul
Non-singular Bounce Cosmology from Lagrange Multiplier $F(R)$ Gravity
PRD Accepted
null
10.1103/PhysRevD.100.084056
null
gr-qc astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we study non-singular{ bounce cosmology} in the context of the Lagrange multiplier generalized $F(R)$ gravity theory of gravity. We specify our study by using a specific variant form of the well known matter{ bounce cosmology}, with scale factor $a(t) = \left(a_0t^2 + 1 \right)^n$, and we demonstrate that for $n < 1/2$, the primordial curvature perturbations are generated deeply in the contraction era. Particularly, we show explicitly that the perturbation modes exit the horizon at a large negative time during the contraction era, which in turn makes the ``low-curvature'' regime, the era for which the calculations of observational indices related to the primordial power spectrum can be considered reliable. Using the reconstruction techniques for the Lagrange multiplier $F(R)$ gravity, we construct the form of effective $F(R)$ gravity that can realize such a cosmological evolution, and we determine the power spectrum of the primordial curvature perturbations. Accordingly, we calculate the spectral index of the primordial curvature perturbations and the tensor-to-scalar ratio, and we confront these with the latest observational data. We also address the issue of stability of the primordial metric perturbations, and to this end, we determine the form of $F(R)$ which realizes the non-singular cosmology for the whole range of cosmic time $-\infty < t < \infty$, by solving the Friedmann equations without the ``low-curvature'' approximation. This study is performed numerically though, due to the high complexity of the resulting differential equations. We also investigate the energy conditions in the present context. The phenomenology of the non-singular bounce is also studied in the context of a standard $F(R)$ gravity.
[ { "created": "Tue, 8 Oct 2019 17:11:41 GMT", "version": "v1" } ]
2020-01-08
[ [ "Nojiri", "Shin'ichi", "" ], [ "Odintsov", "S. D.", "" ], [ "Oikonomou", "V. K.", "" ], [ "Paul", "Tanmoy", "" ] ]
In this work we study non-singular{ bounce cosmology} in the context of the Lagrange multiplier generalized $F(R)$ gravity theory of gravity. We specify our study by using a specific variant form of the well known matter{ bounce cosmology}, with scale factor $a(t) = \left(a_0t^2 + 1 \right)^n$, and we demonstrate that for $n < 1/2$, the primordial curvature perturbations are generated deeply in the contraction era. Particularly, we show explicitly that the perturbation modes exit the horizon at a large negative time during the contraction era, which in turn makes the ``low-curvature'' regime, the era for which the calculations of observational indices related to the primordial power spectrum can be considered reliable. Using the reconstruction techniques for the Lagrange multiplier $F(R)$ gravity, we construct the form of effective $F(R)$ gravity that can realize such a cosmological evolution, and we determine the power spectrum of the primordial curvature perturbations. Accordingly, we calculate the spectral index of the primordial curvature perturbations and the tensor-to-scalar ratio, and we confront these with the latest observational data. We also address the issue of stability of the primordial metric perturbations, and to this end, we determine the form of $F(R)$ which realizes the non-singular cosmology for the whole range of cosmic time $-\infty < t < \infty$, by solving the Friedmann equations without the ``low-curvature'' approximation. This study is performed numerically though, due to the high complexity of the resulting differential equations. We also investigate the energy conditions in the present context. The phenomenology of the non-singular bounce is also studied in the context of a standard $F(R)$ gravity.
1101.1690
Hanno Sahlmann
Hanno Sahlmann and Thomas Thiemann
Chern-Simons theory, Stokes' Theorem, and the Duflo map
26 pages, 8 figures
J.Geom.Phys.61:1104-1121,2011
10.1016/j.geomphys.2011.02.013
APCTP Pre2010-007
gr-qc math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a novel derivation of the expectation values of holonomies in Chern-Simons theory, based on Stokes' Theorem and the functional properties of the Chern-Simons action. It involves replacing the connection by certain functional derivatives under the path integral integral. It turns out that ordering choices have to be made in the process, and we demonstrate that, quite surprisingly, the Duflo isomorphism gives the right ordering, at least in the simple cases that we consider. In this way, we determine the expectation values of unknotted, but possibly linked, holonomy loops for SU(2) and SU(3), and sketch how the method may be applied to more complicated cases. Our manipulations of the path integral are formal but well motivated by a rigorous calculus of integration on spaces of generalized connections which has been developed in the context of loop quantum gravity.
[ { "created": "Mon, 10 Jan 2011 00:21:00 GMT", "version": "v1" } ]
2011-05-26
[ [ "Sahlmann", "Hanno", "" ], [ "Thiemann", "Thomas", "" ] ]
We consider a novel derivation of the expectation values of holonomies in Chern-Simons theory, based on Stokes' Theorem and the functional properties of the Chern-Simons action. It involves replacing the connection by certain functional derivatives under the path integral integral. It turns out that ordering choices have to be made in the process, and we demonstrate that, quite surprisingly, the Duflo isomorphism gives the right ordering, at least in the simple cases that we consider. In this way, we determine the expectation values of unknotted, but possibly linked, holonomy loops for SU(2) and SU(3), and sketch how the method may be applied to more complicated cases. Our manipulations of the path integral are formal but well motivated by a rigorous calculus of integration on spaces of generalized connections which has been developed in the context of loop quantum gravity.
gr-qc/9703008
Renaud Parentani
Renaud Parentani
The interpretation of the solutions of the Wheeler De Witt equation
11 pages, latex, no figures
Phys.Rev. D56 (1997) 4618-4624
10.1103/PhysRevD.56.4618
null
gr-qc
null
We extract transition amplitudes among matter constituents of the universe from the solutions of the Wheeler De Witt equation. The physical interpretation of these solutions is then reached by an analysis of the properties of the transition amplitudes. The interpretation so obtained is based on the current carried by these solutions and confirms ideas put forward by Vilenkin.
[ { "created": "Tue, 4 Mar 1997 11:14:32 GMT", "version": "v1" } ]
2009-10-30
[ [ "Parentani", "Renaud", "" ] ]
We extract transition amplitudes among matter constituents of the universe from the solutions of the Wheeler De Witt equation. The physical interpretation of these solutions is then reached by an analysis of the properties of the transition amplitudes. The interpretation so obtained is based on the current carried by these solutions and confirms ideas put forward by Vilenkin.
2007.05988
Grigory Volovik
G.E. Volovik
Double Hawking temperature in de Sitter Universe and cosmological constant problem
7 pages, no figures
null
null
null
gr-qc cond-mat.other hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
As distinct from the black hole physics, the de Sitter thermodynamics is not determined by the cosmological horizon, the effective temperature differs from the Hawking temperature. In particular, the atom in the de Sitter universe experiences thermal activation corresponding to the local temperature, which is twice larger than the Hawking temperature, $T_{\rm loc}=2T_{\rm Hawking}$. The same double Hawking temperature describes the decay of massive scalar field in the de Sitter universe. The reason, why the local temperature is exactly twice the Hawking temperature, follows from the geometry of the de Sitter spacetime. The weakening of the role of the cosmological horizon in de Sitter universe is confirmed by considering Hawking radiation. We discuss the difference between the radiation of particles in the de Sitter spacetime and the Schwinger pair creation in the electric field. We use the stationary Painleve-Gullstrand metric for the de Sitter spacetime, where the particles are created by Hawking radiation from the cosmological horizon, and time independent gauge for the electric field. In these stationary frames the Hamiltonians and the energy spectra of massive particles look rather similar. However, the final results are essentially different. In case of Schwinger pair production the number density of the created pairs grows with time, while in the de Sitter vacuum the number density of the created pairs is finite. The latter suggests that Hawking radiation from the cosmological horizon does not lead to instability of the de Sitter vacuum. The other mechanisms of instability are required for the dynamical solution of the cosmological constant problem. We consider the possible role of the local temperature $T_{\rm loc}=2T_{\rm H}$ in the decay of the de Sitter space-time due to the energy exchange between the vacuum energy and relativistic matter with this temperature.
[ { "created": "Sun, 12 Jul 2020 13:37:22 GMT", "version": "v1" }, { "created": "Sat, 29 Aug 2020 15:01:50 GMT", "version": "v2" }, { "created": "Mon, 7 Sep 2020 13:12:44 GMT", "version": "v3" }, { "created": "Mon, 26 Oct 2020 09:26:03 GMT", "version": "v4" }, { "created": "Sun, 6 Dec 2020 11:11:30 GMT", "version": "v5" }, { "created": "Mon, 19 Apr 2021 09:34:34 GMT", "version": "v6" }, { "created": "Wed, 21 Apr 2021 12:16:26 GMT", "version": "v7" } ]
2021-04-22
[ [ "Volovik", "G. E.", "" ] ]
As distinct from the black hole physics, the de Sitter thermodynamics is not determined by the cosmological horizon, the effective temperature differs from the Hawking temperature. In particular, the atom in the de Sitter universe experiences thermal activation corresponding to the local temperature, which is twice larger than the Hawking temperature, $T_{\rm loc}=2T_{\rm Hawking}$. The same double Hawking temperature describes the decay of massive scalar field in the de Sitter universe. The reason, why the local temperature is exactly twice the Hawking temperature, follows from the geometry of the de Sitter spacetime. The weakening of the role of the cosmological horizon in de Sitter universe is confirmed by considering Hawking radiation. We discuss the difference between the radiation of particles in the de Sitter spacetime and the Schwinger pair creation in the electric field. We use the stationary Painleve-Gullstrand metric for the de Sitter spacetime, where the particles are created by Hawking radiation from the cosmological horizon, and time independent gauge for the electric field. In these stationary frames the Hamiltonians and the energy spectra of massive particles look rather similar. However, the final results are essentially different. In case of Schwinger pair production the number density of the created pairs grows with time, while in the de Sitter vacuum the number density of the created pairs is finite. The latter suggests that Hawking radiation from the cosmological horizon does not lead to instability of the de Sitter vacuum. The other mechanisms of instability are required for the dynamical solution of the cosmological constant problem. We consider the possible role of the local temperature $T_{\rm loc}=2T_{\rm H}$ in the decay of the de Sitter space-time due to the energy exchange between the vacuum energy and relativistic matter with this temperature.
gr-qc/0512005
Sang Pyo Kim
Sang Pyo Kim (Kunsan Nat'l Univ.)
Quasinormal modes of black holes and dissipative open systems
RevTex 9 pages, one figure; Talks at Black Hole V, Canada, 2005 and 9th Italian-Korean Symposium, Korea, 2005; note and references added in proof
J.Korean Phys.Soc. 49 (2006) 764-772
null
null
gr-qc astro-ph hep-th
null
After explaining the physical origin of the quasinormal modes of perturbations in the background geometry of a black hole, I critically review the recent proposal for the quantization of the black-hole area based on the real part of quasinormal modes. As instantons due to the barriers of black-hole potentials lie at the root of a discrete set of complex quasinormal modes frequencies, it is likely that the physics of quasinormal modes can be learned from quantum theory. I propose a connection of a system of quasinormal modes of black holes with a dissipative open system, in particular, the Feshbach-Tikochinsky oscillator. This argument is supported in part by the fact that these two systems have the same group structure SU(1,1) and the same group representation of Hamiltonians; thereby, their quantum states exhibit the same behavior.
[ { "created": "Thu, 1 Dec 2005 01:08:09 GMT", "version": "v1" }, { "created": "Tue, 3 Jan 2006 13:15:14 GMT", "version": "v2" } ]
2007-05-23
[ [ "Kim", "Sang Pyo", "", "Kunsan Nat'l Univ." ] ]
After explaining the physical origin of the quasinormal modes of perturbations in the background geometry of a black hole, I critically review the recent proposal for the quantization of the black-hole area based on the real part of quasinormal modes. As instantons due to the barriers of black-hole potentials lie at the root of a discrete set of complex quasinormal modes frequencies, it is likely that the physics of quasinormal modes can be learned from quantum theory. I propose a connection of a system of quasinormal modes of black holes with a dissipative open system, in particular, the Feshbach-Tikochinsky oscillator. This argument is supported in part by the fact that these two systems have the same group structure SU(1,1) and the same group representation of Hamiltonians; thereby, their quantum states exhibit the same behavior.
2012.02432
Matsuno Satsuki
Hideki Ishihara, Satsuki Matsuno
Solutions to the Einstein-Maxwell-Current System with Sasakian maifolds
16 pages, no figures
null
null
null
gr-qc math.DG
http://creativecommons.org/publicdomain/zero/1.0/
We construct stationary solutions to the Einstein-Maxwell-current system by using the Sasakian manifold for the three-dimensional space. Both the magnetic field and the electric current in the solution are specified by the contact form of the Sasakian manifold. The solutions contain an arbitrary function that describes inhomogeneity of the number density of the charged particles, and the function determines the curvature of the space.
[ { "created": "Fri, 4 Dec 2020 07:02:28 GMT", "version": "v1" } ]
2020-12-07
[ [ "Ishihara", "Hideki", "" ], [ "Matsuno", "Satsuki", "" ] ]
We construct stationary solutions to the Einstein-Maxwell-current system by using the Sasakian manifold for the three-dimensional space. Both the magnetic field and the electric current in the solution are specified by the contact form of the Sasakian manifold. The solutions contain an arbitrary function that describes inhomogeneity of the number density of the charged particles, and the function determines the curvature of the space.
1709.05577
Marcos Ramirez
Marcos A. Ramirez
Vacuum thin shells in Einstein-Gauss-Bonnet brane-world cosmology
20 pages, 5 figures
Class.Quant.Grav. 35 (2018) no.8, 085004
10.1088/1361-6382/aab0da
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we construct new solutions of the Einstein-Gauss-Bonnet field equations in an isotropic Shiromizu-Maeda-Sasaki brane-world setting which represent a couple of $Z_2$-symmetric vacuum thin shells splitting from the central brane, and explore the main properties of the dynamics of the system. The matching of the separating vacuum shells with the brane-world is as smooth as possible and all matter fields are restricted to the brane. We prove the existence of these solutions, derive the criteria for their existence, analyse some fundamental aspects or their evolution and demonstrate the possibility of constructing cosmological examples that exhibit this feature at early times. We also comment on the possible implications for cosmology and the relation of this system with the thermodynamic instability of highly symmetric vacuum solutions of Lovelock theory.
[ { "created": "Sat, 16 Sep 2017 22:59:50 GMT", "version": "v1" }, { "created": "Fri, 16 Feb 2018 17:51:45 GMT", "version": "v2" } ]
2018-03-26
[ [ "Ramirez", "Marcos A.", "" ] ]
In this paper we construct new solutions of the Einstein-Gauss-Bonnet field equations in an isotropic Shiromizu-Maeda-Sasaki brane-world setting which represent a couple of $Z_2$-symmetric vacuum thin shells splitting from the central brane, and explore the main properties of the dynamics of the system. The matching of the separating vacuum shells with the brane-world is as smooth as possible and all matter fields are restricted to the brane. We prove the existence of these solutions, derive the criteria for their existence, analyse some fundamental aspects or their evolution and demonstrate the possibility of constructing cosmological examples that exhibit this feature at early times. We also comment on the possible implications for cosmology and the relation of this system with the thermodynamic instability of highly symmetric vacuum solutions of Lovelock theory.
1508.04943
Oleg Evnin
Ben Craps, Oleg Evnin, Joris Vanhoof
Ultraviolet asymptotics and singular dynamics of AdS perturbations
15 pages; v4: typos in equation (33) corrected
JHEP 1510 (2015) 079
10.1007/JHEP10(2015)079
null
gr-qc hep-th nlin.CD
http://creativecommons.org/licenses/by-nc-sa/4.0/
Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude epsilon on time-scales of order 1/epsilon^2. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive relations for the coefficients of the time-averaged theory that are likely to be useful for evaluating them more efficiently in numerical simulations.
[ { "created": "Thu, 20 Aug 2015 10:27:17 GMT", "version": "v1" }, { "created": "Fri, 4 Sep 2015 04:47:14 GMT", "version": "v2" }, { "created": "Thu, 29 Oct 2015 05:47:01 GMT", "version": "v3" }, { "created": "Thu, 12 Nov 2015 01:27:58 GMT", "version": "v4" } ]
2015-11-13
[ [ "Craps", "Ben", "" ], [ "Evnin", "Oleg", "" ], [ "Vanhoof", "Joris", "" ] ]
Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude epsilon on time-scales of order 1/epsilon^2. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive relations for the coefficients of the time-averaged theory that are likely to be useful for evaluating them more efficiently in numerical simulations.
gr-qc/0007025
Izumi Tanaka
T.Kawai, K. Shibata, I.Tanaka
Generalized Equivalence Principle in Extended New General Relativity
35 pages
Prog.Theor.Phys. 104 (2000) 505-530; Erratum-ibid. 104 (2000) 1115-1116
10.1143/PTP.104.505
null
gr-qc
null
In extended new general relativity, which is formulated as a reduction of $\bar{Poincar\'e} $gauge theory of gravity whose gauge group is the covering group of the Poincar\'e group, we study the problem of whether the total energy-momentum, total angular momentum and total charge are equal to the corresponding quantities of the gravitational source. We examine this for charged axi-symmetric solutions of gravitational field equations. Our main concern is the restriction on the asymptotic form of the gravitational field variables imposed by the requirement that physical quantities of the total system are equivalent to the corresponding quantities of the charged rotating source body. This requirement can be regarded as an equivalence principle in a generalized sense.
[ { "created": "Thu, 13 Jul 2000 04:37:52 GMT", "version": "v1" }, { "created": "Fri, 1 Dec 2000 04:12:21 GMT", "version": "v2" } ]
2009-10-31
[ [ "Kawai", "T.", "" ], [ "Shibata", "K.", "" ], [ "Tanaka", "I.", "" ] ]
In extended new general relativity, which is formulated as a reduction of $\bar{Poincar\'e} $gauge theory of gravity whose gauge group is the covering group of the Poincar\'e group, we study the problem of whether the total energy-momentum, total angular momentum and total charge are equal to the corresponding quantities of the gravitational source. We examine this for charged axi-symmetric solutions of gravitational field equations. Our main concern is the restriction on the asymptotic form of the gravitational field variables imposed by the requirement that physical quantities of the total system are equivalent to the corresponding quantities of the charged rotating source body. This requirement can be regarded as an equivalence principle in a generalized sense.
2306.00870
Aneta Wojnar
Eva Lope-Oter, Aneta Wojnar
Constraining Palatini gravity with GR-independent equations of state for neutron stars
39 pages, 20 figures, 4 tables, accepted to JCAP
JCAP 02 (2024) 017
10.1088/1475-7516/2024/02/017
null
gr-qc astro-ph.HE hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate how to construct GR-independent equations of state. We emphasize the importance of using theory-based principles instead of relying solely on astrophysical observables and General Relativity (GR). We build a set of equations of state based on first principles, including chiral perturbation theory and perturbation theory in quantum chromodynamics. Interpolation methods are employed to assume thermodynamic stability and causality in the intermediate region. These equations of state are then used to constrain quadratic Palatini $f(\mathcal R)$ gravity, indicating that the parameter lies within the range $-6.47 \lesssim \beta \lesssim 1.99$ km$^2$. Additionally, we briefly discuss the problem of phase transitions and twin stars.
[ { "created": "Thu, 1 Jun 2023 16:30:05 GMT", "version": "v1" }, { "created": "Fri, 19 Jan 2024 11:59:10 GMT", "version": "v2" } ]
2024-02-12
[ [ "Lope-Oter", "Eva", "" ], [ "Wojnar", "Aneta", "" ] ]
We demonstrate how to construct GR-independent equations of state. We emphasize the importance of using theory-based principles instead of relying solely on astrophysical observables and General Relativity (GR). We build a set of equations of state based on first principles, including chiral perturbation theory and perturbation theory in quantum chromodynamics. Interpolation methods are employed to assume thermodynamic stability and causality in the intermediate region. These equations of state are then used to constrain quadratic Palatini $f(\mathcal R)$ gravity, indicating that the parameter lies within the range $-6.47 \lesssim \beta \lesssim 1.99$ km$^2$. Additionally, we briefly discuss the problem of phase transitions and twin stars.
1409.4680
Michael Coughlin
Michael Coughlin and Jan Harms
Constraining the gravitational wave energy density of the Universe in the Range 0.1 Hz to 1 Hz using the Apollo Seismic Array
null
null
10.1103/PhysRevD.90.102001
null
gr-qc astro-ph.IM
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we describe an analysis of Apollo era lunar seismic data that places an upper limit on an isotropic stochastic gravitational-wave background integrated over a year in the frequency range 0.1\,Hz -- 1\,Hz. We find that because the Moon's ambient noise background is much quieter than that of the Earth, significant improvements over an Earth based analysis were made. We find an upper limit of $\Omega_{\rm GW}<1.2\times 10^{5}$, which is three orders of magnitude smaller than a similar analysis of a global network of broadband seismometers on Earth and the best limits in this band to date. We also discuss the benefits of a potential Earth-Moon correlation search and compute the time-dependent overlap reduction function required for such an analysis. For this search, we find an upper limit an order of magnitude larger than the Moon-Moon search.
[ { "created": "Tue, 16 Sep 2014 15:55:01 GMT", "version": "v1" }, { "created": "Tue, 7 Oct 2014 18:15:02 GMT", "version": "v2" }, { "created": "Sat, 11 Oct 2014 20:22:43 GMT", "version": "v3" } ]
2015-06-22
[ [ "Coughlin", "Michael", "" ], [ "Harms", "Jan", "" ] ]
In this paper, we describe an analysis of Apollo era lunar seismic data that places an upper limit on an isotropic stochastic gravitational-wave background integrated over a year in the frequency range 0.1\,Hz -- 1\,Hz. We find that because the Moon's ambient noise background is much quieter than that of the Earth, significant improvements over an Earth based analysis were made. We find an upper limit of $\Omega_{\rm GW}<1.2\times 10^{5}$, which is three orders of magnitude smaller than a similar analysis of a global network of broadband seismometers on Earth and the best limits in this band to date. We also discuss the benefits of a potential Earth-Moon correlation search and compute the time-dependent overlap reduction function required for such an analysis. For this search, we find an upper limit an order of magnitude larger than the Moon-Moon search.
gr-qc/0602009
Pavel Krtous
Jiri Bicak, Pavel Krtous
Fields of accelerated sources: Born in de Sitter
37 pages, 23 figures, reformatted version of the paper published in JMP; low-resolution figures due to arXiv size restrictions; for the version with high-resolution figures see http://utf.mff.cuni.cz/~krtous/papers/
J.Math.Phys. 46 (2005) 102504
10.1063/1.2009647
null
gr-qc
null
This paper deals thoroughly with the scalar and electromagnetic fields of uniformly accelerated charges in de Sitter spacetime. It gives details and makes various extensions of our Physical Review Letter from 2002. The basic properties of the classical Born solutions representing two uniformly accelerated charges in flat spacetime are first summarized. The worldlines of uniformly accelerated particles in de Sitter universe are defined and described in a number of coordinate frames, some of them being of cosmological significance, the other are tied naturally to the particles. The scalar and electromagnetic fields due to the accelerated charges are constructed by using conformal relations between Minkowski and de Sitter space. The properties of the generalized `cosmological' Born solutions are analyzed and elucidated in various coordinate systems. In particular, a limiting procedure is demonstrated which brings the cosmological Born fields in de Sitter space back to the classical Born solutions in Minkowski space. In an extensive Appendix, which can be used independently of the main text, nine families of coordinate systems in de Sitter spacetime are described analytically and illustrated graphically in a number of conformal diagrams.
[ { "created": "Thu, 2 Feb 2006 14:12:59 GMT", "version": "v1" } ]
2015-06-25
[ [ "Bicak", "Jiri", "" ], [ "Krtous", "Pavel", "" ] ]
This paper deals thoroughly with the scalar and electromagnetic fields of uniformly accelerated charges in de Sitter spacetime. It gives details and makes various extensions of our Physical Review Letter from 2002. The basic properties of the classical Born solutions representing two uniformly accelerated charges in flat spacetime are first summarized. The worldlines of uniformly accelerated particles in de Sitter universe are defined and described in a number of coordinate frames, some of them being of cosmological significance, the other are tied naturally to the particles. The scalar and electromagnetic fields due to the accelerated charges are constructed by using conformal relations between Minkowski and de Sitter space. The properties of the generalized `cosmological' Born solutions are analyzed and elucidated in various coordinate systems. In particular, a limiting procedure is demonstrated which brings the cosmological Born fields in de Sitter space back to the classical Born solutions in Minkowski space. In an extensive Appendix, which can be used independently of the main text, nine families of coordinate systems in de Sitter spacetime are described analytically and illustrated graphically in a number of conformal diagrams.
1506.06153
Carlos O. Lousto
James Healy, Ian Ruchlin, Carlos O. Lousto, and Yosef Zlochower
High Energy Collisions of Black Holes Numerically Revisited
11 pages, 10 figures
Phys. Rev. D 94, 104020 (2016)
10.1103/PhysRevD.94.104020
null
gr-qc astro-ph.HE hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use fully nonlinear numerical relativity techniques to study high energy head-on collision of nonspinning, equal-mass black holes to estimate the maximum gravitational radiation emitted by these systems. Our simulations include improvements in the construction of initial data, subsequent full numerical evolutions, and the computation of waveforms at infinity. The new initial data significantly reduces the spurious radiation content, allowing for initial speeds much closer to the speed of light, i.e. $v\sim0.99c$. Using these new techniques, We estimate the maximum radiated energy from head-on collisions to be $E_{\text{max}}/M_{\text{ADM}}=0.13\pm0.01$. This value differs from the second-order perturbative $(0.164)$ and zero-frequency-limit $(0.17)$ analytic computations, but is close to those obtained by thermodynamic arguments $(0.134)$ and by previous numerical estimates $(0.14\pm0.03)$.
[ { "created": "Fri, 19 Jun 2015 20:36:58 GMT", "version": "v1" }, { "created": "Wed, 24 Aug 2016 20:00:37 GMT", "version": "v2" } ]
2016-11-15
[ [ "Healy", "James", "" ], [ "Ruchlin", "Ian", "" ], [ "Lousto", "Carlos O.", "" ], [ "Zlochower", "Yosef", "" ] ]
We use fully nonlinear numerical relativity techniques to study high energy head-on collision of nonspinning, equal-mass black holes to estimate the maximum gravitational radiation emitted by these systems. Our simulations include improvements in the construction of initial data, subsequent full numerical evolutions, and the computation of waveforms at infinity. The new initial data significantly reduces the spurious radiation content, allowing for initial speeds much closer to the speed of light, i.e. $v\sim0.99c$. Using these new techniques, We estimate the maximum radiated energy from head-on collisions to be $E_{\text{max}}/M_{\text{ADM}}=0.13\pm0.01$. This value differs from the second-order perturbative $(0.164)$ and zero-frequency-limit $(0.17)$ analytic computations, but is close to those obtained by thermodynamic arguments $(0.134)$ and by previous numerical estimates $(0.14\pm0.03)$.
0905.0789
Salvatore Antoci
Salvatore Antoci
The propagation of waves in Einstein's unified field theory as shown by two exact solutions
12 pages. Added footnote 6 details proof of propagation with the fundamental velocity in the wave zone
Nuovo Cim.B124:619-630,2010
10.1393/ncb/i2009-10783-9
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The propagation of waves in two space dimensions exhibited by two exact solutions to the field equations of Einstein's unified field theory is investigated under the assumption that the metric s_{ik} is the one already chosen by Kursunoglu and by H\'ely in the years 1952-1954. It is shown that, for both exact solutions, with this choice of the metric the propagation of the waves occurs in the wave zone with the fundamental velocity (ds^2=0).
[ { "created": "Wed, 6 May 2009 09:30:08 GMT", "version": "v1" }, { "created": "Tue, 29 Sep 2009 10:34:52 GMT", "version": "v2" } ]
2010-11-11
[ [ "Antoci", "Salvatore", "" ] ]
The propagation of waves in two space dimensions exhibited by two exact solutions to the field equations of Einstein's unified field theory is investigated under the assumption that the metric s_{ik} is the one already chosen by Kursunoglu and by H\'ely in the years 1952-1954. It is shown that, for both exact solutions, with this choice of the metric the propagation of the waves occurs in the wave zone with the fundamental velocity (ds^2=0).
1405.5334
Prasobh C.B
C.B. Prasobh, V.C. Kuriakose
Quasinormal Modes of Lovelock Black Holes
null
null
10.1140/epjc/s10052-014-3136-4
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The quasinormal modes of metric perturbations in asymptotically flat black hole spacetimes in the Lovelock model are calculated for different spacetime dimensions and higher orders of curvature. It is analytically established that in the asymptotic limit $l \rightarrow \infty$, the imaginary parts of the quasi normal frequencies become constant for tensor, scalar as well as vector perturbations. Numerical calculation shows that this indeed is the case. Also, the real and imaginary parts of the quasinormal modes are seen to increase as the order of the theory $k$ increases. The real part of the modes decreases as the spacetime dimension $d$ increases, indicating the presence of lower frequency modes in higher dimensions. Also, it is seen that the modes are roughly isospectral at very high values of the spacetime dimension $d$.
[ { "created": "Wed, 21 May 2014 08:50:25 GMT", "version": "v1" } ]
2015-06-19
[ [ "Prasobh", "C. B.", "" ], [ "Kuriakose", "V. C.", "" ] ]
The quasinormal modes of metric perturbations in asymptotically flat black hole spacetimes in the Lovelock model are calculated for different spacetime dimensions and higher orders of curvature. It is analytically established that in the asymptotic limit $l \rightarrow \infty$, the imaginary parts of the quasi normal frequencies become constant for tensor, scalar as well as vector perturbations. Numerical calculation shows that this indeed is the case. Also, the real and imaginary parts of the quasinormal modes are seen to increase as the order of the theory $k$ increases. The real part of the modes decreases as the spacetime dimension $d$ increases, indicating the presence of lower frequency modes in higher dimensions. Also, it is seen that the modes are roughly isospectral at very high values of the spacetime dimension $d$.
2101.00785
Junji Jia
Haotian Liu and Junji Jia
Time delay in the strong field limit for null and timelike signals and its simple interpretation
24 pages, 3 figures
null
10.1140/epjc/s10052-021-09659-8
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gravitational lensing can happen not only for null signal but also timelike signals such as neutrinos and massive gravitational waves in some theories beyond GR. In this work we study the time delay between different relativistic images formed by signals with arbitrary asymptotic velocity $v$ in general static and spherically symmetric spacetimes. A perturbative method is used to calculate the total travel time in the strong field limit, which is found to be in quasi-series of the small parameter $a=1-b_c/b$ where $b$ is the impact parameter and $b_c$ is its critical value. The coefficients of the series are completely fixed by the behaviour of the metric functions near the particle sphere $r_c$ and only the first term of the series contains a weak logarithmic divergence. The time delay $\Delta t_{n,m}$ to the leading non-trivial order was shown to equal the particle sphere circumference divided by the local signal velocity and multiplied by the winding number and the redshift factor. By assuming the Sgr A* supermassive black hole is a Hayward one, we were able to validate the quasi-series form of the total time, and reveal the effects of the spacetime parameter $l$, the signal velocity $v$ and the source/detector coordinate difference $\Delta\phi_{sd}$ on the time delay. It is found that as $l$ increase from 0 to its critical value $l_c$, both $r_c$ and $\Delta t_{n,m}$ decrease. The variation of $\Delta t_{n+1,n}$ for $l$ from 0 to $l_c$ can be as large as $7.2\times 10^1$ [s], whose measurement then can be used to constrain the value of $l$. While for ultra-relativistic neutrino or gravitational wave, the variation of $\Delta t_{n,m}$ is too small to be resolved. The dependence of $\Delta t_{n,-n}$ on $\Delta \phi_{sd}$ shows that to temporally resolve the two sequences of images from opposite sides of the lens, $|\Delta \phi_{sd}-\pi|$ has to be larger than certain value.
[ { "created": "Mon, 4 Jan 2021 05:54:47 GMT", "version": "v1" } ]
2021-10-27
[ [ "Liu", "Haotian", "" ], [ "Jia", "Junji", "" ] ]
Gravitational lensing can happen not only for null signal but also timelike signals such as neutrinos and massive gravitational waves in some theories beyond GR. In this work we study the time delay between different relativistic images formed by signals with arbitrary asymptotic velocity $v$ in general static and spherically symmetric spacetimes. A perturbative method is used to calculate the total travel time in the strong field limit, which is found to be in quasi-series of the small parameter $a=1-b_c/b$ where $b$ is the impact parameter and $b_c$ is its critical value. The coefficients of the series are completely fixed by the behaviour of the metric functions near the particle sphere $r_c$ and only the first term of the series contains a weak logarithmic divergence. The time delay $\Delta t_{n,m}$ to the leading non-trivial order was shown to equal the particle sphere circumference divided by the local signal velocity and multiplied by the winding number and the redshift factor. By assuming the Sgr A* supermassive black hole is a Hayward one, we were able to validate the quasi-series form of the total time, and reveal the effects of the spacetime parameter $l$, the signal velocity $v$ and the source/detector coordinate difference $\Delta\phi_{sd}$ on the time delay. It is found that as $l$ increase from 0 to its critical value $l_c$, both $r_c$ and $\Delta t_{n,m}$ decrease. The variation of $\Delta t_{n+1,n}$ for $l$ from 0 to $l_c$ can be as large as $7.2\times 10^1$ [s], whose measurement then can be used to constrain the value of $l$. While for ultra-relativistic neutrino or gravitational wave, the variation of $\Delta t_{n,m}$ is too small to be resolved. The dependence of $\Delta t_{n,-n}$ on $\Delta \phi_{sd}$ shows that to temporally resolve the two sequences of images from opposite sides of the lens, $|\Delta \phi_{sd}-\pi|$ has to be larger than certain value.
gr-qc/0309038
Alessandro D. A. M. Spallicci
Marco Ferraris (1), Alessandro D.A.M. Spallicci (2) ((1) Dip. Matematica, Univ. di Torino, (2) Observatoire de la Cote d'Azur, Nice)
Solutions of all one-dimensional wave equations with time independent potential and separable variables
10 pages, 1 figure. Accepted by Gen. Rel. Grav. J.
Gen.Rel.Grav. 36 (2004) 1955-1963
10.1023/B:GERG.0000036053.75204.a2
null
gr-qc math-ph math.AP math.MP
null
Exact solutions, in terms of special functions, of all wave equations $% u_{xx} - u_{tt} = V(x) u(t,x)$, characterised by eight inequivalent time independent potentials and by variable separation, have been found. The real valueness of the solutions from computer algebra programs is not always manifest and in this work we provide ready to use solutions. We discussed especially the potential $\cosh^{-2}x (m_1 + m_2 \sinh x)$. Such potential approximates the Schwarzschild black hole potential for even parity.
[ { "created": "Sun, 7 Sep 2003 08:37:53 GMT", "version": "v1" }, { "created": "Wed, 21 Jan 2004 13:55:15 GMT", "version": "v2" } ]
2009-11-10
[ [ "Ferraris", "Marco", "" ], [ "Spallicci", "Alessandro D. A. M.", "" ] ]
Exact solutions, in terms of special functions, of all wave equations $% u_{xx} - u_{tt} = V(x) u(t,x)$, characterised by eight inequivalent time independent potentials and by variable separation, have been found. The real valueness of the solutions from computer algebra programs is not always manifest and in this work we provide ready to use solutions. We discussed especially the potential $\cosh^{-2}x (m_1 + m_2 \sinh x)$. Such potential approximates the Schwarzschild black hole potential for even parity.
2208.10260
Ernesto Contreras
E. Contreras, E. Fuenmayor, G. Abell\'an
Uncharged and charged anisotropic like--Durgapal stellar model with vanishing complexity
null
Eur. Phys. J. C 82, 187 (2022)
10.1140/epjc/s10052-022-10154-x
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we use the vanishing complexity factor as a supplementary condition to construct uncharged and charged like--Durgapal models. We provide the $g_{tt}$ component of the metric of the well-known Durgapal IV and V solutions and a particular form for the anisotropy, related to the electric charge, to close the system of differential equations. The physical acceptance of the models is discussed.
[ { "created": "Thu, 18 Aug 2022 20:34:35 GMT", "version": "v1" } ]
2022-08-31
[ [ "Contreras", "E.", "" ], [ "Fuenmayor", "E.", "" ], [ "Abellán", "G.", "" ] ]
In this work we use the vanishing complexity factor as a supplementary condition to construct uncharged and charged like--Durgapal models. We provide the $g_{tt}$ component of the metric of the well-known Durgapal IV and V solutions and a particular form for the anisotropy, related to the electric charge, to close the system of differential equations. The physical acceptance of the models is discussed.
2310.06876
Telem Ibungochouba Singh
Y. Onika Laxmi, Ningthoujam Media and T. Ibungochouba Singh
P-v criticality of charged Reissner-Nordstr{\"o}m-de Sitter black hole under the influence of Lorentz violation theory
null
null
null
null
gr-qc hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, the modified Hawking radiation and the P-v criticality of Reissner-Nordstr{\"o}m-de Sitter (RNdS) black hole are investigated by using Dirac equation with Lorentz violation theory in curved space time. Taking cosmological constant as the thermodynamic pressure and its conjugate quantity as thermodynamic volume, the analogy between the RNdS black hole in the ensemble with fixed charge and van der Waals liquid-gas system is derived. We also study the equation of state, critical exponents, critical point, heat capacity, entropy correction, Gibbs free energy. It is worth mentioning that the critical temperature, entropy, Gibbs free energy and Helmholtz free energy are modified but the critical exponents are found to be unchanged due to the influence of Lorentz violation theory. We observe that the number of Hawking-Page critical point increases due to Lorentz violation theory.
[ { "created": "Tue, 10 Oct 2023 04:33:46 GMT", "version": "v1" } ]
2023-10-12
[ [ "Laxmi", "Y. Onika", "" ], [ "Media", "Ningthoujam", "" ], [ "Singh", "T. Ibungochouba", "" ] ]
In this paper, the modified Hawking radiation and the P-v criticality of Reissner-Nordstr{\"o}m-de Sitter (RNdS) black hole are investigated by using Dirac equation with Lorentz violation theory in curved space time. Taking cosmological constant as the thermodynamic pressure and its conjugate quantity as thermodynamic volume, the analogy between the RNdS black hole in the ensemble with fixed charge and van der Waals liquid-gas system is derived. We also study the equation of state, critical exponents, critical point, heat capacity, entropy correction, Gibbs free energy. It is worth mentioning that the critical temperature, entropy, Gibbs free energy and Helmholtz free energy are modified but the critical exponents are found to be unchanged due to the influence of Lorentz violation theory. We observe that the number of Hawking-Page critical point increases due to Lorentz violation theory.
gr-qc/0101021
Marc Mars
Marc Mars
The Wahlquist-Newman solution
LaTeX, 18 pages, no figures. Accepted for publication in Phys. Rev. D
Phys.Rev. D63 (2001) 064022
10.1103/PhysRevD.63.064022
null
gr-qc
null
Based on a geometrical property which holds both for the Kerr metric and for the Wahlquist metric we argue that the Kerr metric is a vacuum subcase of the Wahlquist perfect-fluid solution. The Kerr-Newman metric is a physically preferred charged generalization of the Kerr metric. We discuss which geometric property makes this metric so special and claim that a charged generalization of the Wahlquist metric satisfying a similar property should exist. This is the Wahlquist-Newman metric, which we present explicitly in this paper. This family of metrics has eight essential parameters and contains the Kerr-Newman-de Sitter and the Wahlquist metrics, as well as the whole Pleba\'nski limit of the rotating C-metric, as particular cases. We describe the basic geometric properties of the Wahlquist-Newman metric, including the electromagnetic field and its sources, the static limit of the family and the extension of the spacetime across the horizon.
[ { "created": "Fri, 5 Jan 2001 15:29:35 GMT", "version": "v1" } ]
2009-11-07
[ [ "Mars", "Marc", "" ] ]
Based on a geometrical property which holds both for the Kerr metric and for the Wahlquist metric we argue that the Kerr metric is a vacuum subcase of the Wahlquist perfect-fluid solution. The Kerr-Newman metric is a physically preferred charged generalization of the Kerr metric. We discuss which geometric property makes this metric so special and claim that a charged generalization of the Wahlquist metric satisfying a similar property should exist. This is the Wahlquist-Newman metric, which we present explicitly in this paper. This family of metrics has eight essential parameters and contains the Kerr-Newman-de Sitter and the Wahlquist metrics, as well as the whole Pleba\'nski limit of the rotating C-metric, as particular cases. We describe the basic geometric properties of the Wahlquist-Newman metric, including the electromagnetic field and its sources, the static limit of the family and the extension of the spacetime across the horizon.
0808.2510
Jeffrey Kaplan
Jeffrey D. Kaplan, David A. Nichols, and Kip S. Thorne
Post-Newtonian Approximation in Maxwell-Like Form
v4: Revised for resubmission to Phys Rev D, 6 pages. v3: Reformulated in terms of DSX papers. Submitted to Phys Rev D, 6 pages. v2: Added references. Changed definitions & conventions
Phys.Rev.D80:124014,2009
10.1103/PhysRevD.80.124014
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The equations of the linearized first post-Newtonian approximation to general relativity are often written in "gravitoelectromagnetic" Maxwell-like form, since that facilitates physical intuition. Damour, Soffel and Xu (DSX) (as a side issue in their complex but elegant papers on relativistic celestial mechanics) have expressed the first post-Newtonian approximation, including all nonlinearities, in Maxwell-like form. This paper summarizes that DSX Maxwell-like formalism (which is not easily extracted from their celestial mechanics papers), and then extends it to include the post-Newtonian (Landau-Lifshitz-based) gravitational momentum density, momentum flux (i.e. gravitational stress tensor) and law of momentum conservation in Maxwell-like form. The authors and their colleagues have found these Maxwell-like momentum tools useful for developing physical intuition into numerical-relativity simulations of compact binaries with spin.
[ { "created": "Tue, 19 Aug 2008 00:21:27 GMT", "version": "v1" }, { "created": "Wed, 17 Sep 2008 21:34:01 GMT", "version": "v2" }, { "created": "Wed, 25 Feb 2009 20:55:54 GMT", "version": "v3" }, { "created": "Fri, 11 Sep 2009 20:51:58 GMT", "version": "v4" } ]
2012-12-13
[ [ "Kaplan", "Jeffrey D.", "" ], [ "Nichols", "David A.", "" ], [ "Thorne", "Kip S.", "" ] ]
The equations of the linearized first post-Newtonian approximation to general relativity are often written in "gravitoelectromagnetic" Maxwell-like form, since that facilitates physical intuition. Damour, Soffel and Xu (DSX) (as a side issue in their complex but elegant papers on relativistic celestial mechanics) have expressed the first post-Newtonian approximation, including all nonlinearities, in Maxwell-like form. This paper summarizes that DSX Maxwell-like formalism (which is not easily extracted from their celestial mechanics papers), and then extends it to include the post-Newtonian (Landau-Lifshitz-based) gravitational momentum density, momentum flux (i.e. gravitational stress tensor) and law of momentum conservation in Maxwell-like form. The authors and their colleagues have found these Maxwell-like momentum tools useful for developing physical intuition into numerical-relativity simulations of compact binaries with spin.
2007.10116
Alexander Zhidenko
R. A. Konoplya and A. Zhidenko
Simply rotating higher dimensional black holes in Einstein-Gauss-Bonnet theory
12 pages, 1 figure
Phys. Rev. D 102, 084030 (2020)
10.1103/PhysRevD.102.084030
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using perturbative expansion in terms of powers of the rotation parameter $a$ we construct the axisymmetric and asymptotically flat black-hole metric in the $D$-dimensional Einstein-Gauss-Bonnet theory. In five-dimensional spacetime we find two solutions to the field equations, describing the asymptotically flat black holes, though only one of them is perturbative in mass, that is, goes over into the Minkowski spacetime when the black-hole mass goes to zero. We obtain the perturbative black-hole solution up to the order $O(\alpha a^3)$ for any $D$, where $\alpha$ is the Gauss-Bonnet coupling, while the $D=5$ solution which is nonperturbative in mass is found in analytic form up to the order $O(\alpha a^7)$. In order to check the convergence of the expansion in $a$ we analyze characteristics of photon orbits in this spacetime and compute frequencies of the photon orbits and radius of the photon sphere.
[ { "created": "Sun, 12 Jul 2020 21:53:03 GMT", "version": "v1" }, { "created": "Wed, 14 Oct 2020 17:52:58 GMT", "version": "v2" } ]
2020-10-15
[ [ "Konoplya", "R. A.", "" ], [ "Zhidenko", "A.", "" ] ]
Using perturbative expansion in terms of powers of the rotation parameter $a$ we construct the axisymmetric and asymptotically flat black-hole metric in the $D$-dimensional Einstein-Gauss-Bonnet theory. In five-dimensional spacetime we find two solutions to the field equations, describing the asymptotically flat black holes, though only one of them is perturbative in mass, that is, goes over into the Minkowski spacetime when the black-hole mass goes to zero. We obtain the perturbative black-hole solution up to the order $O(\alpha a^3)$ for any $D$, where $\alpha$ is the Gauss-Bonnet coupling, while the $D=5$ solution which is nonperturbative in mass is found in analytic form up to the order $O(\alpha a^7)$. In order to check the convergence of the expansion in $a$ we analyze characteristics of photon orbits in this spacetime and compute frequencies of the photon orbits and radius of the photon sphere.
gr-qc/9912036
Wang Mian
Mian Wang
The Scalar-Tensor Inflationary Cosmology
17 pages, LaTex, no figure, changed some parameters and the tables
Phys.Rev. D61 (2000) 123511
10.1103/PhysRevD.61.123511
null
gr-qc astro-ph hep-ph
null
In this paper the scalar-tensor theory of gravity is assumed to describe the evolution of the universe and the gravitational scalar $\phi$ is ascribed to play the role of inflaton. The theory is characterized by the specified coupling function $\omega(\phi)$ and the cosmological function $\lambda(\phi)$. The function $\lambda(\phi)$ is nearly constant for $0<\phi<0.1$ and $\lambda(1)=0$. The functions $\lambda(\phi)$ and $\omega(\phi)$ provide a double-well potential for the motion of $\phi(t)$. Inflation commences and ends naturally by the dynamics of the scalar field. The energy density of matter increases steadily during inflation. When the constant $\Gamma$ in the action is determined by the present matter density, the temperature at the end of inflation is of the order of $10^{14} GeV$ in no need of reheating. Furthermore, the gravitational scalar is just the cold dark matter that men seek for.
[ { "created": "Fri, 10 Dec 1999 08:09:30 GMT", "version": "v1" }, { "created": "Fri, 3 Mar 2000 14:09:08 GMT", "version": "v2" } ]
2009-10-31
[ [ "Wang", "Mian", "" ] ]
In this paper the scalar-tensor theory of gravity is assumed to describe the evolution of the universe and the gravitational scalar $\phi$ is ascribed to play the role of inflaton. The theory is characterized by the specified coupling function $\omega(\phi)$ and the cosmological function $\lambda(\phi)$. The function $\lambda(\phi)$ is nearly constant for $0<\phi<0.1$ and $\lambda(1)=0$. The functions $\lambda(\phi)$ and $\omega(\phi)$ provide a double-well potential for the motion of $\phi(t)$. Inflation commences and ends naturally by the dynamics of the scalar field. The energy density of matter increases steadily during inflation. When the constant $\Gamma$ in the action is determined by the present matter density, the temperature at the end of inflation is of the order of $10^{14} GeV$ in no need of reheating. Furthermore, the gravitational scalar is just the cold dark matter that men seek for.
gr-qc/0202002
Gil de Oliveira-Neto
G. Oliveira-Neto
Naked singularities in three-dimensions
Revtex version, 11 pages and 1 eps figure
Int.J.Mod.Phys.D12:791-800,2003
10.1142/S0218271803003335
null
gr-qc
null
We study an analytical solution to the Einstein's equations in 2+1-dimensions, representing the self-similar collapse of a circularly symmetric, minimally coupled, massless, scalar field. Depending on the value of certain parameters, this solution represents the formation of naked singularities. Since our solution is asymptotically flat, these naked singularities may be relevant for the weak cosmic censorship conjecture in 2+1-dimensions.
[ { "created": "Fri, 1 Feb 2002 17:57:19 GMT", "version": "v1" } ]
2014-11-17
[ [ "Oliveira-Neto", "G.", "" ] ]
We study an analytical solution to the Einstein's equations in 2+1-dimensions, representing the self-similar collapse of a circularly symmetric, minimally coupled, massless, scalar field. Depending on the value of certain parameters, this solution represents the formation of naked singularities. Since our solution is asymptotically flat, these naked singularities may be relevant for the weak cosmic censorship conjecture in 2+1-dimensions.