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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
gr-qc/9909047 | Tatyana P. Shestakova | V. A. Savchenko, T. P. Shestakova, G. M. Vereshkov | Quantum geometrodynamics of the Bianchi IX model in extended phase space | LaTeX, 18 pages, to be published in Int. J. Mod. Phys. A | Int.J.Mod.Phys. A14 (1999) 4473-4490 | 10.1142/S0217751X99002098 | null | gr-qc | null | A way of constructing mathematically correct quantum geometrodynamics of a
closed universe is presented. The resulting theory appears to be
gauge-noninvariant and thus consistent with the observation conditions of a
closed universe, by that being considerably distinguished from the conventional
Wheeler - DeWitt one. For the Bianchi-IX cosmological model it is shown that a
normalizable wave function of the Universe depends on time, allows the standard
probability interpretation and satisfies a gauge-noninvariant dynamical
Schrodinger equation. The Wheeler - DeWitt quantum geometrodynamics is
represented by a singular, BRST-invariant solution to the Schrodinger equation
having no property of normalizability.
| [
{
"created": "Wed, 15 Sep 1999 15:00:10 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Savchenko",
"V. A.",
""
],
[
"Shestakova",
"T. P.",
""
],
[
"Vereshkov",
"G. M.",
""
]
] | A way of constructing mathematically correct quantum geometrodynamics of a closed universe is presented. The resulting theory appears to be gauge-noninvariant and thus consistent with the observation conditions of a closed universe, by that being considerably distinguished from the conventional Wheeler - DeWitt one. For the Bianchi-IX cosmological model it is shown that a normalizable wave function of the Universe depends on time, allows the standard probability interpretation and satisfies a gauge-noninvariant dynamical Schrodinger equation. The Wheeler - DeWitt quantum geometrodynamics is represented by a singular, BRST-invariant solution to the Schrodinger equation having no property of normalizability. |
1212.6963 | I. V. Kanatchikov | I. V. Kanatchikov | On precanonical quantization of gravity in spin connection variables | 10 pages. v2: mostly corrects few typos. v3: published version in a
different latex format and titles in the references. v4: corrects typo in eq.
7 | AIP Conf.Proc. 1514 (2012) 73-76 | 10.1063/1.4791728 | null | gr-qc hep-th math-ph math.MP quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The basics of precanonical quantization and its relation to the functional
Schr\"odinger picture in QFT are briefly outlined. The approach is applied to
quantization of Einstein's gravity in vielbein and spin connection variables
and leads to a quantum dynamics described by the covariant Schr\"odinger
equation for the transition amplitudes on the bundle of spin connection
coefficients over the space-time, that yields a novel quantum description of
space-time geometry. A toy model of precanonical quantum cosmology based on the
example of flat FLRW universe is considered.
| [
{
"created": "Mon, 31 Dec 2012 20:24:43 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Feb 2013 03:50:27 GMT",
"version": "v2"
},
{
"created": "Wed, 6 Mar 2013 22:54:58 GMT",
"version": "v3"
},
{
"created": "Tue, 27 Jan 2015 13:16:44 GMT",
"version": "v4"
}
] | 2015-06-12 | [
[
"Kanatchikov",
"I. V.",
""
]
] | The basics of precanonical quantization and its relation to the functional Schr\"odinger picture in QFT are briefly outlined. The approach is applied to quantization of Einstein's gravity in vielbein and spin connection variables and leads to a quantum dynamics described by the covariant Schr\"odinger equation for the transition amplitudes on the bundle of spin connection coefficients over the space-time, that yields a novel quantum description of space-time geometry. A toy model of precanonical quantum cosmology based on the example of flat FLRW universe is considered. |
1111.6607 | Leonardo Gualtieri | V. Ferrari, L. Gualtieri, A. Maselli | Tidal interaction in compact binaries: a post-Newtonian affine framework | 15 pages, 1 table, 3 figures. Minor changes to match the version
published on Phys. Rev. D | null | 10.1103/PhysRevD.85.044045 | null | gr-qc astro-ph.SR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop a semi-analytical approach, based on the post-Newtonian expansion
and on the affine approximation, to model the tidal deformation of neutron
stars in the coalescence of black hole-neutron star or neutron star-neutron
star binaries. Our equations describe, in a unified framework, both the system
orbital evolution, and the neutron star deformations. These are driven by the
tidal tensor, which we expand at 1/c^3 post-Newtonian order, including spin
terms. We test the theoretical framework by simulating black hole-neutron star
coalescence up to the onset of mass shedding, which we determine by comparing
the shape of the star with the Roche lobe. We validate our approach by
comparing our results with those of fully relativistic, numerical simulations.
| [
{
"created": "Mon, 28 Nov 2011 21:04:44 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Nov 2011 19:05:05 GMT",
"version": "v2"
},
{
"created": "Mon, 19 Mar 2012 16:24:49 GMT",
"version": "v3"
}
] | 2015-06-03 | [
[
"Ferrari",
"V.",
""
],
[
"Gualtieri",
"L.",
""
],
[
"Maselli",
"A.",
""
]
] | We develop a semi-analytical approach, based on the post-Newtonian expansion and on the affine approximation, to model the tidal deformation of neutron stars in the coalescence of black hole-neutron star or neutron star-neutron star binaries. Our equations describe, in a unified framework, both the system orbital evolution, and the neutron star deformations. These are driven by the tidal tensor, which we expand at 1/c^3 post-Newtonian order, including spin terms. We test the theoretical framework by simulating black hole-neutron star coalescence up to the onset of mass shedding, which we determine by comparing the shape of the star with the Roche lobe. We validate our approach by comparing our results with those of fully relativistic, numerical simulations. |
1510.05213 | Neda Farhangkhah | N. Farhangkhah | New solutions of exotic charged black holes and their stability | 17 pages, 6 figures | Int. J. Mod. Phys. Vol. 25, No. 2 (2016) 1650030 | 10.1142/S0218271816500309 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We find a class of charged black hole solutions in third order Lovelock
Gravity. To obtain this class of solutions, we are not confined to the usual
assumption of maximal symmetry on the horizon and will consider the solution
whose boundary is Einstein space with supplementary conditions on its Weyl
tensor. The Weyl tensor of such exotic horizons exposes two charge-like
parameter to the solution. These parameters in addition with the electric
charge, cause different features in compare with the charged solution with
constant-curvature horizon. For this class of asymptotically (A)dS solutions,
the electric charge dominates the behavior of the metric as r goes to zero, and
thus the central singularity is always timelike. We also compute the
thermodynamic quantities for these solutions and will show that the first law
of thermodynamics is satisfied. We also show that the extreme black holes with
nonconstant-curvature horizons whose Ricci scalar are zero or a positive
constant could exist depending on the value of the electric charge and
charged-like parameters. Finally, we investigate the stability of the black
holes by analyzing the behavior of free energy and heat capacity specially in
the limits of small and large horizon radius. We will show that in contrast
with charged solution with constant-curvature horizon, a phase transition
occurs between very small and small black holes from a stable phase to an
unstable one, while the large black holes show stability to both perturbative
and non-perturbative fluctuations.
| [
{
"created": "Sun, 18 Oct 2015 09:29:19 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Jan 2016 09:27:58 GMT",
"version": "v2"
}
] | 2018-04-12 | [
[
"Farhangkhah",
"N.",
""
]
] | We find a class of charged black hole solutions in third order Lovelock Gravity. To obtain this class of solutions, we are not confined to the usual assumption of maximal symmetry on the horizon and will consider the solution whose boundary is Einstein space with supplementary conditions on its Weyl tensor. The Weyl tensor of such exotic horizons exposes two charge-like parameter to the solution. These parameters in addition with the electric charge, cause different features in compare with the charged solution with constant-curvature horizon. For this class of asymptotically (A)dS solutions, the electric charge dominates the behavior of the metric as r goes to zero, and thus the central singularity is always timelike. We also compute the thermodynamic quantities for these solutions and will show that the first law of thermodynamics is satisfied. We also show that the extreme black holes with nonconstant-curvature horizons whose Ricci scalar are zero or a positive constant could exist depending on the value of the electric charge and charged-like parameters. Finally, we investigate the stability of the black holes by analyzing the behavior of free energy and heat capacity specially in the limits of small and large horizon radius. We will show that in contrast with charged solution with constant-curvature horizon, a phase transition occurs between very small and small black holes from a stable phase to an unstable one, while the large black holes show stability to both perturbative and non-perturbative fluctuations. |
2111.04716 | Tomi Koivisto | Jose Beltr\'an Jim\'enez, Tomi S. Koivisto | Noether charges in the geometrical trinity of gravity | V2: 7 pages. Added several clarifications, including an appendix. To
appear as a PRD letter | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Noether currents are derived in a generic metric-affine theory of
gravity, and the holographic nature of the gravitational entropy and
energy-momentum is clarified. The main result is the verification of the
canonical resolution to the energy-momentum problem in the Noether formalism.
| [
{
"created": "Mon, 8 Nov 2021 18:49:46 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Jan 2022 19:21:31 GMT",
"version": "v2"
}
] | 2022-01-17 | [
[
"Jiménez",
"Jose Beltrán",
""
],
[
"Koivisto",
"Tomi S.",
""
]
] | The Noether currents are derived in a generic metric-affine theory of gravity, and the holographic nature of the gravitational entropy and energy-momentum is clarified. The main result is the verification of the canonical resolution to the energy-momentum problem in the Noether formalism. |
1209.2016 | Andreas G. A. Pithis | Andreas G. A. Pithis | The Gibbs paradox, Black hole entropy and the thermodynamics of isolated
horizons | 8 pages, closest to the published version; taken from the author's
diploma thesis | Phys. Rev. D 87, 084061 (2013) | 10.1103/PhysRevD.87.084061 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This letter presents a new, solely thermodynamical argument for considering
the states of the quantum isolated horizon of a black hole as distinguishable.
We claim that only if the states are distinguishable, the thermodynamic entropy
is an extensive quantity and can be well-defined. To show this, we make a
comparison with a classical ideal gas system whose statistical description
makes only sense if an additional 1/N!-factor is included in the state counting
in order to cure the Gibbs paradox. The case of the statistical description of
a quantum isolated horizon is elaborated, to make the claim evident.
| [
{
"created": "Thu, 6 Sep 2012 17:47:16 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Nov 2012 23:08:59 GMT",
"version": "v2"
},
{
"created": "Mon, 15 Apr 2013 15:53:56 GMT",
"version": "v3"
}
] | 2016-11-26 | [
[
"Pithis",
"Andreas G. A.",
""
]
] | This letter presents a new, solely thermodynamical argument for considering the states of the quantum isolated horizon of a black hole as distinguishable. We claim that only if the states are distinguishable, the thermodynamic entropy is an extensive quantity and can be well-defined. To show this, we make a comparison with a classical ideal gas system whose statistical description makes only sense if an additional 1/N!-factor is included in the state counting in order to cure the Gibbs paradox. The case of the statistical description of a quantum isolated horizon is elaborated, to make the claim evident. |
gr-qc/9909012 | Jiri Podolsky | J. Podolsky, K. Vesely | Smearing of chaos in sandwich pp-waves | 17 pages, LaTeX, 9 figures, to be published in Class.Quantum Grav | Class.Quant.Grav. 16 (1999) 3599-3618 | null | null | gr-qc | null | Recent results demonstrating the chaotic behavior of geodesics in
non-homogeneous vacuum pp-wave solutions are generalized. Here we concentrate
on motion in non-homogeneous sandwich pp-waves and show that chaos smears as
the duration of these gravitational waves is reduced. As the number of radial
bounces of any geodesic decreases, the outcome channels to infinity become
fuzzy, and thus the fractal structure of the initial conditions characterizing
chaos is cut at lower and lower levels. In the limit of impulsive waves, the
motion is fully non-chaotic. This is proved by presenting the geodesics in a
simple explicit form which permits a physical interpretation, and demonstrates
the focusing effect. It is shown that a circle of test particles is deformed by
the impulse into a family of closed hypotrochoidal curves in the transversal
plane. These are deformed in the longitudinal direction in such a way that a
specific closed caustic surface is formed.
| [
{
"created": "Fri, 3 Sep 1999 14:39:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Podolsky",
"J.",
""
],
[
"Vesely",
"K.",
""
]
] | Recent results demonstrating the chaotic behavior of geodesics in non-homogeneous vacuum pp-wave solutions are generalized. Here we concentrate on motion in non-homogeneous sandwich pp-waves and show that chaos smears as the duration of these gravitational waves is reduced. As the number of radial bounces of any geodesic decreases, the outcome channels to infinity become fuzzy, and thus the fractal structure of the initial conditions characterizing chaos is cut at lower and lower levels. In the limit of impulsive waves, the motion is fully non-chaotic. This is proved by presenting the geodesics in a simple explicit form which permits a physical interpretation, and demonstrates the focusing effect. It is shown that a circle of test particles is deformed by the impulse into a family of closed hypotrochoidal curves in the transversal plane. These are deformed in the longitudinal direction in such a way that a specific closed caustic surface is formed. |
1910.02121 | Panagiota Kanti | Burkhard Kleihaus, Jutta Kunz and Panagiota Kanti | Particle-like ultracompact objects in Einstein-scalar-Gauss-Bonnet
theories | 7 pages, 4 figures, the analysis on the observable effects was
extended, a new plot, comments and references were added, version published
in Physics Letters B | null | 10.1016/j.physletb.2020.135401 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a new type of ultracompact objects, featuring lightrings and
echoes in the gravitational-wave spectrum. These particle-like solutions arise
in Einstein-scalar-Gauss-Bonnet theories in four spacetime dimensions,
representing globally regular spacetime manifolds. The scalar field diverges at
the center, but the effective stress-energy tensor is free from pathologies. We
determine their domain of existence and compare with wormhole solutions, black
holes and the Fisher solution.
| [
{
"created": "Fri, 4 Oct 2019 19:51:38 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Apr 2020 10:11:46 GMT",
"version": "v2"
}
] | 2020-04-22 | [
[
"Kleihaus",
"Burkhard",
""
],
[
"Kunz",
"Jutta",
""
],
[
"Kanti",
"Panagiota",
""
]
] | We present a new type of ultracompact objects, featuring lightrings and echoes in the gravitational-wave spectrum. These particle-like solutions arise in Einstein-scalar-Gauss-Bonnet theories in four spacetime dimensions, representing globally regular spacetime manifolds. The scalar field diverges at the center, but the effective stress-energy tensor is free from pathologies. We determine their domain of existence and compare with wormhole solutions, black holes and the Fisher solution. |
2203.02297 | Calin Iuliu Lazaroiu | Elena Mirela Babalic, Calin Iuliu Lazaroiu | The infrared behavior of tame two-field cosmological models | 52 pages, numerous figures; v2:some typos corrected, references added | Nucl. Phys. B 983 (2022), 115929 | 10.1016/j.nuclphysb.2022.115929 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the first order infared behavior of tame hyperbolizable two-field
cosmological models, defined as those classical two-field models whose scalar
manifold is a connected, oriented and topologically finite hyperbolizable
Riemann surface $(\Sigma,\mathcal{G})$ and whose scalar potential $\Phi$ admits
a positive and Morse extension to the end compactification of $\Sigma$. We
achieve this by determining the universal forms of the asymptotic gradient flow
of the classical effective potential $V$ with respect to the uniformizing
metric $G$ near all interior critical points and ends of $\Sigma$, finding that
some of the latter act like fictitious but exotic stationary points of the
gradient flow. We also compare these results with numerical studies of
cosmological orbits. For critical cusp ends, we find that cosmological curves
have transient quasiperiodic behavior but are eventually attracted or repelled
by the cusp along principal geodesic orbits determined by the extended
effective potential. This behavior is approximated in the infrared by that of
gradient flow curves near the cusp.
| [
{
"created": "Thu, 3 Mar 2022 13:43:57 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Mar 2022 10:18:46 GMT",
"version": "v2"
}
] | 2022-08-30 | [
[
"Babalic",
"Elena Mirela",
""
],
[
"Lazaroiu",
"Calin Iuliu",
""
]
] | We study the first order infared behavior of tame hyperbolizable two-field cosmological models, defined as those classical two-field models whose scalar manifold is a connected, oriented and topologically finite hyperbolizable Riemann surface $(\Sigma,\mathcal{G})$ and whose scalar potential $\Phi$ admits a positive and Morse extension to the end compactification of $\Sigma$. We achieve this by determining the universal forms of the asymptotic gradient flow of the classical effective potential $V$ with respect to the uniformizing metric $G$ near all interior critical points and ends of $\Sigma$, finding that some of the latter act like fictitious but exotic stationary points of the gradient flow. We also compare these results with numerical studies of cosmological orbits. For critical cusp ends, we find that cosmological curves have transient quasiperiodic behavior but are eventually attracted or repelled by the cusp along principal geodesic orbits determined by the extended effective potential. This behavior is approximated in the infrared by that of gradient flow curves near the cusp. |
gr-qc/0406007 | Patricio S. Letelier | D. Vog and P. S. Letelier | Exact Relativistic Static Charged Dust Disks and Non-axisymmetric
Structures | Classical and Quantum Gravity (in press). 15 pages, LaTex, 8 .eps
figs | Class.Quant.Grav. 21 (2004) 3369-3378 | 10.1088/0264-9381/21/14/003 | null | gr-qc | null | The well-known ``displace, cut and reflect'' method used to generate disks
from given solutions of Einstein field equations is applied to the
superposition of twoextreme Reissner-Nordstrom black holes to construct disks
made of charged dust and alsonon-axisymmetric planar distributions of charged
dust on the z=0 plane. They are symmetric with respect to twoor one coordinate
axes, depending whether the black holes have equal or unequal masses,
respectively.For these non-axisymmetric distributions of matter we also study
the effective potential for geodesic motion of neutral test particles.
| [
{
"created": "Wed, 2 Jun 2004 19:25:49 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Vog",
"D.",
""
],
[
"Letelier",
"P. S.",
""
]
] | The well-known ``displace, cut and reflect'' method used to generate disks from given solutions of Einstein field equations is applied to the superposition of twoextreme Reissner-Nordstrom black holes to construct disks made of charged dust and alsonon-axisymmetric planar distributions of charged dust on the z=0 plane. They are symmetric with respect to twoor one coordinate axes, depending whether the black holes have equal or unequal masses, respectively.For these non-axisymmetric distributions of matter we also study the effective potential for geodesic motion of neutral test particles. |
2308.05328 | Paolo Valtancoli | P. Valtancoli | Bumblebee gravity with cosmological constant | 8 pages, no figures | null | null | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | We show how to find exact black hole solutions in bumblebee gravity with
cosmological constant including BTZ black holes.
| [
{
"created": "Thu, 10 Aug 2023 04:08:13 GMT",
"version": "v1"
}
] | 2023-08-11 | [
[
"Valtancoli",
"P.",
""
]
] | We show how to find exact black hole solutions in bumblebee gravity with cosmological constant including BTZ black holes. |
gr-qc/9804035 | Justino Martinez | L. Herrera, A. Di Prisco and J. Martinez | Thermal conduction before relaxation in slowly rotating fluids | Latex 2.09 (RevTex style) 19 pages To be published in Journal of
Mathematical Physics | J.Math.Phys. 39 (1998) 3260-3270 | 10.1063/1.532252 | null | gr-qc astro-ph | null | For slowly rotating fluids, we establish the existence of a critical point
similar to the one found for non-rotating systems. As the fluid approaches the
critical point, the effective inertial mass of any fluid element decreases,
vanishing at that point and changing of sign beyond it. This result implies
that first order perturbative method is not always reliable to study
dissipative processes ocurring before relaxation. Physical consequences that
might follow from this effect are commented.
| [
{
"created": "Thu, 16 Apr 1998 10:28:21 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Herrera",
"L.",
""
],
[
"Di Prisco",
"A.",
""
],
[
"Martinez",
"J.",
""
]
] | For slowly rotating fluids, we establish the existence of a critical point similar to the one found for non-rotating systems. As the fluid approaches the critical point, the effective inertial mass of any fluid element decreases, vanishing at that point and changing of sign beyond it. This result implies that first order perturbative method is not always reliable to study dissipative processes ocurring before relaxation. Physical consequences that might follow from this effect are commented. |
gr-qc/0303058 | Kaiki Taro Inoue | Kaiki Taro Inoue, Takahiro Tanaka | Gravitational Waves from Sub-lunar Mass Primordial Black Hole Binaries -
A New Probe of Extradimensions | 4 pages, 1 figure, typos corrected | Phys.Rev.Lett. 91 (2003) 021101 | 10.1103/PhysRevLett.91.021101 | null | gr-qc astro-ph hep-ph | null | In many braneworld models, gravity is largely modified at the electro-weak
scale ~ 1TeV. In such models, primordial black holes (PBHs) with lunar mass M ~
10^{-7}M_sun might have been produced when the temperature of the universe was
at ~ 1TeV. If a significant fraction of the dark halo of our galaxy consists of
these lunar mass PBHs, a huge number of BH binaries will exist in our
neighborhood. Third generation detectors such as EURO can detect gravitational
waves from these binaries, and can also determine their chirp mass. With a new
detector designed to be sensitive at high frequency bands greater than 1 kHz,
the existence of extradimensions could be confirmed.
| [
{
"created": "Sun, 16 Mar 2003 02:42:37 GMT",
"version": "v1"
},
{
"created": "Sun, 27 Jul 2003 05:48:23 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Inoue",
"Kaiki Taro",
""
],
[
"Tanaka",
"Takahiro",
""
]
] | In many braneworld models, gravity is largely modified at the electro-weak scale ~ 1TeV. In such models, primordial black holes (PBHs) with lunar mass M ~ 10^{-7}M_sun might have been produced when the temperature of the universe was at ~ 1TeV. If a significant fraction of the dark halo of our galaxy consists of these lunar mass PBHs, a huge number of BH binaries will exist in our neighborhood. Third generation detectors such as EURO can detect gravitational waves from these binaries, and can also determine their chirp mass. With a new detector designed to be sensitive at high frequency bands greater than 1 kHz, the existence of extradimensions could be confirmed. |
gr-qc/0303116 | Abel Camacho | Abel Camacho and Alfredo Macias (Dept. of Physics, Universidad
Autonoma Metropolitana--Iztapalapa) | Space--time torsion contribution to quantum interference phases | Contribution to the Proceedings of the Meeting ''Topics in
Mathematical Physics, General Relativity, and Cosmology''. On the Occasion of
the 75th Birthday of Jerzy F. Plebanski. CINVESTAV, September, 17th--20th,
2002 | Phys.Lett. B617 (2005) 118-123 | 10.1016/j.physletb.2005.04.065 | null | gr-qc quant-ph | null | From the latest experimental readouts in this context an intriguing
discrepancy has been elicited. Indeed, theory and experiment dissent by one per
cent, and though this fact could be a consequence of the mounting of the
experimental device, it might also embody a difference between the way in which
gravity behaves in classical and quantum mechanics. In this work the effects,
upon the interference pattern, of space--time torsion will be analyzed heeding
its coupling with the spin of the neutron beam. It will be proved that, even
with this contribution, there is enough leeway for a further discussion of the
validity of the equivalence principle in nonrelativistic quantum mechanics.
| [
{
"created": "Mon, 31 Mar 2003 18:58:56 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Camacho",
"Abel",
"",
"Dept. of Physics, Universidad\n Autonoma Metropolitana--Iztapalapa"
],
[
"Macias",
"Alfredo",
"",
"Dept. of Physics, Universidad\n Autonoma Metropolitana--Iztapalapa"
]
] | From the latest experimental readouts in this context an intriguing discrepancy has been elicited. Indeed, theory and experiment dissent by one per cent, and though this fact could be a consequence of the mounting of the experimental device, it might also embody a difference between the way in which gravity behaves in classical and quantum mechanics. In this work the effects, upon the interference pattern, of space--time torsion will be analyzed heeding its coupling with the spin of the neutron beam. It will be proved that, even with this contribution, there is enough leeway for a further discussion of the validity of the equivalence principle in nonrelativistic quantum mechanics. |
gr-qc/0308032 | Pavel Krtous | Ioannis Kouletsis, Petr Hajicek, Jiri Bicak | Gauge-invariant Hamiltonian dynamics of cylindrical gravitational waves | 16 pages, 1 figure | Phys.Rev. D68 (2003) 104013 | 10.1103/PhysRevD.68.104013 | null | gr-qc hep-th | null | The model of cylindrical gravitational waves is employed to work out and
check a recent proposal in Ref. [11] how a diffeomorphism-invariant Hamiltonian
dynamics is to be constructed. The starting point is the action by Ashtekar and
Pierri because it contains the boundary term that makes it differentiable for
non-trivial variations at infinity. With the help of parametrization at
infinity, the notion of gauge transformation is clearly separated from that of
asymptotic symmetry. The symplectic geometry of asymptotic symmetries and
asymptotic time is described and the role of the asymptotic structures in
defining a zero-motion frame for the Hamiltonian dynamics of Dirac observables
is explained. Complete sets of Dirac observables associated with the asymptotic
fields are found and the action of the asymptotic symmetries on them is
calculated. The construction of the corresponding quantum theory is sketched:
the Fock space, operators of asymptotic fields, the Hamiltonian and the
scattering matrix are determined.
| [
{
"created": "Mon, 11 Aug 2003 14:38:35 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Kouletsis",
"Ioannis",
""
],
[
"Hajicek",
"Petr",
""
],
[
"Bicak",
"Jiri",
""
]
] | The model of cylindrical gravitational waves is employed to work out and check a recent proposal in Ref. [11] how a diffeomorphism-invariant Hamiltonian dynamics is to be constructed. The starting point is the action by Ashtekar and Pierri because it contains the boundary term that makes it differentiable for non-trivial variations at infinity. With the help of parametrization at infinity, the notion of gauge transformation is clearly separated from that of asymptotic symmetry. The symplectic geometry of asymptotic symmetries and asymptotic time is described and the role of the asymptotic structures in defining a zero-motion frame for the Hamiltonian dynamics of Dirac observables is explained. Complete sets of Dirac observables associated with the asymptotic fields are found and the action of the asymptotic symmetries on them is calculated. The construction of the corresponding quantum theory is sketched: the Fock space, operators of asymptotic fields, the Hamiltonian and the scattering matrix are determined. |
gr-qc/0401081 | Piotr Chrusciel | M. Anderson, P.T. Chrusciel, E. Delay | Non-trivial, static, geodesically complete space-times with a negative
cosmological constant II. $n\ge 5$ | Proceedings of the Strasbourg Meeting on AdS-CFT correspondence,
O.Biquard, V.Turaev, Eds., IRMA Lectures in Mathematics and Theoretical
Physics, de Gruyter, Berlin, New York, in press; latex2e, 39 pages in A4;
minor corrections | null | null | null | gr-qc hep-th math.DG | null | We show that the recent work of Lee [23] implies existence of a large class
of new singularity-free strictly static Lorentzian vacuum solutions of the
Einstein equations with a negative cosmological constant. This holds in all
space-time dimensions greater than or equal to four, and leads both to strictly
static solutions and to black hole solutions. The construction allows in
principle for metrics (whether black hole or not) with Yang-Mills-dilaton
fields interacting with gravity through a Kaluza-Klein coupling.
| [
{
"created": "Mon, 19 Jan 2004 16:07:31 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Jan 2005 15:20:58 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Anderson",
"M.",
""
],
[
"Chrusciel",
"P. T.",
""
],
[
"Delay",
"E.",
""
]
] | We show that the recent work of Lee [23] implies existence of a large class of new singularity-free strictly static Lorentzian vacuum solutions of the Einstein equations with a negative cosmological constant. This holds in all space-time dimensions greater than or equal to four, and leads both to strictly static solutions and to black hole solutions. The construction allows in principle for metrics (whether black hole or not) with Yang-Mills-dilaton fields interacting with gravity through a Kaluza-Klein coupling. |
0812.3336 | Otakar Svitek | Otakar Svitek | The damping of gravitational waves in dust | 7 pages, accepted to Phys. Scr | Phys.Scripta 79:025003,2009 | 10.1088/0031-8949/79/02/025003 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine a simple model of interaction of gravitational waves with matter
(primarily represented by dust). The aim is to investigate a possible damping
effect on the intensity of gravitational wave when passing through media. This
might be important for gravitational wave astronomy when the sources are
obscured by dust or molecular clouds.
| [
{
"created": "Wed, 17 Dec 2008 16:52:35 GMT",
"version": "v1"
}
] | 2010-04-14 | [
[
"Svitek",
"Otakar",
""
]
] | We examine a simple model of interaction of gravitational waves with matter (primarily represented by dust). The aim is to investigate a possible damping effect on the intensity of gravitational wave when passing through media. This might be important for gravitational wave astronomy when the sources are obscured by dust or molecular clouds. |
1611.07367 | Tim Dietrich | Tim Dietrich, Sebastiano Bernuzzi, Maximiliano Ujevic, Wolfgang Tichy | Gravitational waves and mass ejecta from binary neutron star mergers:
Effect of the stars' rotation | 21 pages, 19 figures | Phys. Rev. D 95, 044045 (2017) | 10.1103/PhysRevD.95.044045 | null | gr-qc astro-ph.HE astro-ph.SR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present new (3+1) dimensional numerical relativity simulations of the
binary neutron star (BNS) mergers that take into account the NS spins. We
consider different spin configurations, aligned or antialigned to the orbital
angular momentum, for equal and unequal mass BNS and for two equations of
state. All the simulations employ quasiequilibrium circular initial data in the
constant rotational velocity approach, i.e. they are consistent with Einstein
equations and in hydrodynamical equilibrium. We study the NS rotation effect on
the energetics, the gravitational waves (GWs) and on the possible
electromagnetic (EM) emission associated to dynamical mass ejecta. For
dimensionless spin magnitudes of $\chi\sim0.1$ we find that spin-orbit
interactions and also spin-induced-quadrupole deformations affect the
late-inspiral-merger dynamics. The latter is, however, dominated by finite-size
effects. Spin (tidal) effects contribute to GW phase differences up to 5 (20)
radians accumulated during the last eight orbits to merger. Similarly, after
merger the collapse time of the remnant and the GW spectrogram are affected by
the NSs rotation. Spin effects in dynamical ejecta are clearly observed in
unequal mass systems in which mass ejection originates from the tidal tail of
the companion. Consequently kilonovae and other EM counterparts are affected by
spins. We find that spin aligned to the orbital angular momentum leads to
brighter EM counterparts than antialigned spin with luminosities up to a factor
of two higher.
| [
{
"created": "Tue, 22 Nov 2016 15:36:46 GMT",
"version": "v1"
}
] | 2017-03-08 | [
[
"Dietrich",
"Tim",
""
],
[
"Bernuzzi",
"Sebastiano",
""
],
[
"Ujevic",
"Maximiliano",
""
],
[
"Tichy",
"Wolfgang",
""
]
] | We present new (3+1) dimensional numerical relativity simulations of the binary neutron star (BNS) mergers that take into account the NS spins. We consider different spin configurations, aligned or antialigned to the orbital angular momentum, for equal and unequal mass BNS and for two equations of state. All the simulations employ quasiequilibrium circular initial data in the constant rotational velocity approach, i.e. they are consistent with Einstein equations and in hydrodynamical equilibrium. We study the NS rotation effect on the energetics, the gravitational waves (GWs) and on the possible electromagnetic (EM) emission associated to dynamical mass ejecta. For dimensionless spin magnitudes of $\chi\sim0.1$ we find that spin-orbit interactions and also spin-induced-quadrupole deformations affect the late-inspiral-merger dynamics. The latter is, however, dominated by finite-size effects. Spin (tidal) effects contribute to GW phase differences up to 5 (20) radians accumulated during the last eight orbits to merger. Similarly, after merger the collapse time of the remnant and the GW spectrogram are affected by the NSs rotation. Spin effects in dynamical ejecta are clearly observed in unequal mass systems in which mass ejection originates from the tidal tail of the companion. Consequently kilonovae and other EM counterparts are affected by spins. We find that spin aligned to the orbital angular momentum leads to brighter EM counterparts than antialigned spin with luminosities up to a factor of two higher. |
gr-qc/0301118 | Dzhunushaliev Vladimir | V. Dzhunushaliev | Some properties of a $\Delta-$string | LATEX, 7 pages | Class.Quant.Grav. 20 (2003) 2407-2416 | 10.1088/0264-9381/20/11/329 | null | gr-qc hep-th | null | The properties of 5D gravitational flux tubes are considered. With the cross
section and 5th dimension in the Planck region such tubes can be considered as
string-like objects, namely $\Delta-$strings. A model of attachment of
$\Delta-$string to a spacetime is offered. It is shown that the attachment
point is a model of an electric charge for an observer living in the spacetime.
Magnetic charges are forbidden in this model.
| [
{
"created": "Wed, 29 Jan 2003 03:04:08 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Dzhunushaliev",
"V.",
""
]
] | The properties of 5D gravitational flux tubes are considered. With the cross section and 5th dimension in the Planck region such tubes can be considered as string-like objects, namely $\Delta-$strings. A model of attachment of $\Delta-$string to a spacetime is offered. It is shown that the attachment point is a model of an electric charge for an observer living in the spacetime. Magnetic charges are forbidden in this model. |
2405.06120 | Nils Leif Vu | Nils L. Vu | A discontinuous Galerkin scheme for elliptic equations on extremely
stretched grids | 12 pages, 10 figures. Results are reproducible with the ancillary
input files | null | null | null | gr-qc cs.NA math.NA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Discontinuous Galerkin (DG) methods for solving elliptic equations are
gaining popularity in the computational physics community for their high-order
spectral convergence and their potential for parallelization on computing
clusters. However, problems in numerical relativity with extremely stretched
grids, such as initial data problems for binary black holes that impose
boundary conditions at large distances from the black holes, have proven
challenging for DG methods. To alleviate this problem we have developed a
primal DG scheme that is generically applicable to a large class of elliptic
equations, including problems on curved and extremely stretched grids. The DG
scheme accommodates two widely used initial data formulations in numerical
relativity, namely the puncture formulation and the extended conformal
thin-sandwich (XCTS) formulation. We find that our DG scheme is able to stretch
the grid by a factor of $\sim 10^9$ and hence allows to impose boundary
conditions at large distances. The scheme converges exponentially with
resolution both for the smooth XCTS problem and for the non-smooth puncture
problem. With this method we are able to generate high-quality initial data for
binary black hole problems using a parallelizable DG scheme. The code is
publicly available in the open-source SpECTRE numerical relativity code.
| [
{
"created": "Thu, 9 May 2024 21:54:04 GMT",
"version": "v1"
}
] | 2024-05-13 | [
[
"Vu",
"Nils L.",
""
]
] | Discontinuous Galerkin (DG) methods for solving elliptic equations are gaining popularity in the computational physics community for their high-order spectral convergence and their potential for parallelization on computing clusters. However, problems in numerical relativity with extremely stretched grids, such as initial data problems for binary black holes that impose boundary conditions at large distances from the black holes, have proven challenging for DG methods. To alleviate this problem we have developed a primal DG scheme that is generically applicable to a large class of elliptic equations, including problems on curved and extremely stretched grids. The DG scheme accommodates two widely used initial data formulations in numerical relativity, namely the puncture formulation and the extended conformal thin-sandwich (XCTS) formulation. We find that our DG scheme is able to stretch the grid by a factor of $\sim 10^9$ and hence allows to impose boundary conditions at large distances. The scheme converges exponentially with resolution both for the smooth XCTS problem and for the non-smooth puncture problem. With this method we are able to generate high-quality initial data for binary black hole problems using a parallelizable DG scheme. The code is publicly available in the open-source SpECTRE numerical relativity code. |
gr-qc/9604002 | null | M. Gasperini and M. Giovannini | Normal modes for metric fluctuations in a class of higher-dimensional
backgrounds | 19 pages, LATEX, an explicit example is added to discuss the possible
dependence of the perturbation spectrum on the number of internal dimensions.
To apper in Class. Quantum Grav | Class.Quant.Grav.14:735-747,1997 | 10.1088/0264-9381/14/3/015 | CERN-TH/96-87 | gr-qc astro-ph hep-th | null | We discuss a gauge invariant approach to the theory of cosmological
perturbations in a higher-dimensonal background. We find the normal modes which
diagonalize the perturbed action, for a scalar field minimally coupled to
gravity, in a higher-dimensional manifold M of the Bianchi-type I, under the
assumption that the translations along an isotropic spatial subsection of M are
isometries of the full, perturbed background. We show that, in the absence of
scalar field potential, the canonical variables for scalar and tensor metric
perturbations satisfy exactly the same evolution equation, and we discuss the
possible dependence of the spectrum on the number of internal dimensions.
| [
{
"created": "Mon, 1 Apr 1996 14:21:04 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Jan 1997 08:14:56 GMT",
"version": "v2"
}
] | 2010-04-30 | [
[
"Gasperini",
"M.",
""
],
[
"Giovannini",
"M.",
""
]
] | We discuss a gauge invariant approach to the theory of cosmological perturbations in a higher-dimensonal background. We find the normal modes which diagonalize the perturbed action, for a scalar field minimally coupled to gravity, in a higher-dimensional manifold M of the Bianchi-type I, under the assumption that the translations along an isotropic spatial subsection of M are isometries of the full, perturbed background. We show that, in the absence of scalar field potential, the canonical variables for scalar and tensor metric perturbations satisfy exactly the same evolution equation, and we discuss the possible dependence of the spectrum on the number of internal dimensions. |
1712.05933 | Salvatore Capozziello | Habib Abedi and Salvatore Capozziello | Gravitational waves in modified teleparallel theories of gravity | 9 pages, to be published in Eur.Phys.J. C | null | 10.1140/epjc/s10052-018-5967-x | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Teleparallel theory of gravity and its modifications have been studied
extensively in literature. However, gravitational waves has not been studied
enough in the framework of teleparallelism. In the present study, we discuss
gravitational waves in general theories of teleparallel gravity containing the
torsion scalar $T$, the boundary term $B$ and a scalar field $\phi$. The goal
is to classify possible new polarizations generalizing results presented in
Ref.[15]. We show that, if the boundary term is minimally coupled to the
torsion scalar and the scalar field, gravitational waves have the same
polarization modes of General Relativity.
| [
{
"created": "Sat, 16 Dec 2017 10:37:21 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Jun 2018 20:01:11 GMT",
"version": "v2"
}
] | 2018-07-04 | [
[
"Abedi",
"Habib",
""
],
[
"Capozziello",
"Salvatore",
""
]
] | Teleparallel theory of gravity and its modifications have been studied extensively in literature. However, gravitational waves has not been studied enough in the framework of teleparallelism. In the present study, we discuss gravitational waves in general theories of teleparallel gravity containing the torsion scalar $T$, the boundary term $B$ and a scalar field $\phi$. The goal is to classify possible new polarizations generalizing results presented in Ref.[15]. We show that, if the boundary term is minimally coupled to the torsion scalar and the scalar field, gravitational waves have the same polarization modes of General Relativity. |
2108.11274 | Subhajit Barman | Saumya Ghosh and Subhajit Barman | Hawking effect in an extremal Kerr black hole spacetime | Modified version, to appear in Phys. Rev. D | null | 10.1103/PhysRevD.105.045005 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is well known that extremal black holes do not Hawking radiate, which is
usually realized by taking an extremal limit from the nonextremal case.
However, one cannot perceive the same phenomenon using the Bogoliubov
transformation method starting from an extremal black hole itself, i.e.,
without the limiting case consideration. In that case, the Bogoliubov
coefficients do not satisfy the required normalization condition. In canonical
formulation, which closely mimics the Bogoliubov transformation method, one can
consistently reproduce the vanishing number density of Hawking quanta for an
extremal Kerr black hole. In this method, the relation between the spatial
near-null coordinates, imperative in understanding the Hawking effect, was
approximated into a sum of linear and inverse terms only. In the present work,
we first show that one can reach the same conclusion in canonical formulation
even with the complete relationship between the near-null coordinates, which
contains an additional logarithmic term. It is worth mentioning that in the
nonextremal case, a similar logarithmic term alone leads to the thermal Hawking
radiation. Secondly, we study the case with only the inverse term in the
relation (i.e., when the spatial near-null coordinates associated to the past
and future observers are inversely related to each other) to understand whether
it is the main contributing term in vanishing number density. Third, for a
qualitative realization, we consider a simple thought experiment to understand
the corresponding Hawking temperature and conclude that the inverse term indeed
plays a crucial role in the vanishing number density.
| [
{
"created": "Wed, 25 Aug 2021 14:54:15 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Feb 2022 12:31:33 GMT",
"version": "v2"
}
] | 2022-02-23 | [
[
"Ghosh",
"Saumya",
""
],
[
"Barman",
"Subhajit",
""
]
] | It is well known that extremal black holes do not Hawking radiate, which is usually realized by taking an extremal limit from the nonextremal case. However, one cannot perceive the same phenomenon using the Bogoliubov transformation method starting from an extremal black hole itself, i.e., without the limiting case consideration. In that case, the Bogoliubov coefficients do not satisfy the required normalization condition. In canonical formulation, which closely mimics the Bogoliubov transformation method, one can consistently reproduce the vanishing number density of Hawking quanta for an extremal Kerr black hole. In this method, the relation between the spatial near-null coordinates, imperative in understanding the Hawking effect, was approximated into a sum of linear and inverse terms only. In the present work, we first show that one can reach the same conclusion in canonical formulation even with the complete relationship between the near-null coordinates, which contains an additional logarithmic term. It is worth mentioning that in the nonextremal case, a similar logarithmic term alone leads to the thermal Hawking radiation. Secondly, we study the case with only the inverse term in the relation (i.e., when the spatial near-null coordinates associated to the past and future observers are inversely related to each other) to understand whether it is the main contributing term in vanishing number density. Third, for a qualitative realization, we consider a simple thought experiment to understand the corresponding Hawking temperature and conclude that the inverse term indeed plays a crucial role in the vanishing number density. |
gr-qc/9705045 | Alejandro Jakubi | Luis P. Chimento, Alejandro S. Jakubi and Vicen\c{c} M\'endez | New cosmological solutions and stability analysis in full extended
thermodynamics | 13 pages, LaTeX 2.09. To be published in International Journal of
Modern Physics D | Int.J.Mod.Phys. D7 (1998) 177-188 | 10.1142/S0218271898000140 | null | gr-qc | null | The Einstein's field equations of FRW universes filled with a dissipative
fluid described by full theory of causal transport equations are analyzed. New
exact solutions are found using a non-local transformations on the nonlinear
differential equation for the Hubble factor. The stability of the de Sitter and
asymptotically friedmannian solutions are analyzed using Lyapunov function
method.
| [
{
"created": "Sat, 17 May 1997 01:33:13 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Chimento",
"Luis P.",
""
],
[
"Jakubi",
"Alejandro S.",
""
],
[
"Méndez",
"Vicenç",
""
]
] | The Einstein's field equations of FRW universes filled with a dissipative fluid described by full theory of causal transport equations are analyzed. New exact solutions are found using a non-local transformations on the nonlinear differential equation for the Hubble factor. The stability of the de Sitter and asymptotically friedmannian solutions are analyzed using Lyapunov function method. |
1603.07571 | Tao Zhou | Tao Zhou | Lorentz gauge and Coulomb gauge for tetrad field of gravity | 5 pages, no figure, comments are welcome | Universe 8, 659 (2022) | 10.3390/universe8120659 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In general relativity, an inertial frame can only be established in a small
region of spacetime, and locally inertial frames are mathematically represented
by a tetrad field in gravity. The tetrad field is not unique due to the freedom
to perform Lorentz transformations in locally inertial frames, and there exists
freedom to choose the locally inertial frame at each spacetime point. The local
Lorentz transformations are known as non-Abelian gauge transformations for the
tetrad field, and to fix the gauge freedom, corresponding to the Lorentz gauge
$\partial^\mu\mathcal{A}_\mu=0$ and Coulomb gauge $\partial^i\mathcal{A}_i=0$
in electrodynamics, the Lorentz gauge and Coulomb gauge for the tetrad field
are proposed in the present work. Moreover, properties of the Lorentz gauge and
Coulomb gauge for tetrad field are discussed, which show the similarities to
those in electromagnetic field.
| [
{
"created": "Sun, 20 Mar 2016 16:12:51 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Dec 2022 08:33:50 GMT",
"version": "v2"
}
] | 2022-12-16 | [
[
"Zhou",
"Tao",
""
]
] | In general relativity, an inertial frame can only be established in a small region of spacetime, and locally inertial frames are mathematically represented by a tetrad field in gravity. The tetrad field is not unique due to the freedom to perform Lorentz transformations in locally inertial frames, and there exists freedom to choose the locally inertial frame at each spacetime point. The local Lorentz transformations are known as non-Abelian gauge transformations for the tetrad field, and to fix the gauge freedom, corresponding to the Lorentz gauge $\partial^\mu\mathcal{A}_\mu=0$ and Coulomb gauge $\partial^i\mathcal{A}_i=0$ in electrodynamics, the Lorentz gauge and Coulomb gauge for the tetrad field are proposed in the present work. Moreover, properties of the Lorentz gauge and Coulomb gauge for tetrad field are discussed, which show the similarities to those in electromagnetic field. |
2302.06928 | Wan Cong Ms | Piotr T. Chru\'sciel and Wan Cong | Gluing variations | Proof for extending vacuum metric on truncated cone extended; typos
corrected; now, 30 pages main text + 7 pages appendix, 8 figures | null | 10.1088/1361-6382/ace494 | null | gr-qc math-ph math.MP | http://creativecommons.org/licenses/by-sa/4.0/ | We establish several results on gluing/embedding/extending geometric
structures in vacuum spacetimes with a cosmological constant in any spacetime
dimensions $d\ge 4$, with emphasis on characteristic data. A useful tool is
provided by the notion of submanifold-data of order $k$. As an application of
our methods we prove that vacuum Cauchy data on a spacelike Cauchy surface with
boundary can always be extended to vacuum data defined beyond the boundary.
| [
{
"created": "Tue, 14 Feb 2023 09:31:07 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Jul 2023 01:19:44 GMT",
"version": "v2"
}
] | 2023-08-02 | [
[
"Chruściel",
"Piotr T.",
""
],
[
"Cong",
"Wan",
""
]
] | We establish several results on gluing/embedding/extending geometric structures in vacuum spacetimes with a cosmological constant in any spacetime dimensions $d\ge 4$, with emphasis on characteristic data. A useful tool is provided by the notion of submanifold-data of order $k$. As an application of our methods we prove that vacuum Cauchy data on a spacelike Cauchy surface with boundary can always be extended to vacuum data defined beyond the boundary. |
1401.1280 | Farhad Darabi | F. Darabi, A. Parsiya | Vector inflation by kinetic coupled gravity | 9 pages | IJMPD, Volume 23, Issue 8, id. 1450069 (2014) | 10.1142/S0218271814500692 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Vector inflation is a newly established model where inflation is driven by
non-minimally coupled massive vector fields with a potential term. This model
is similar to the model of chaotic inflation with scalar fields, except that
for vector fields the isotropy of expansion is achieved either by considering a
triplet of orthogonal vector fields or $N$ randomly oriented independent vector
fields. We introduce a new version of vector inflation where the vector field
has no potential term but is non-minimally coupled to gravity through the
kinetic term. The non-minimal coupling is established by introducing the
Einstein tensor besides the metric tensor within the kinetic term of the vector
field.
| [
{
"created": "Tue, 7 Jan 2014 06:02:30 GMT",
"version": "v1"
}
] | 2014-10-06 | [
[
"Darabi",
"F.",
""
],
[
"Parsiya",
"A.",
""
]
] | Vector inflation is a newly established model where inflation is driven by non-minimally coupled massive vector fields with a potential term. This model is similar to the model of chaotic inflation with scalar fields, except that for vector fields the isotropy of expansion is achieved either by considering a triplet of orthogonal vector fields or $N$ randomly oriented independent vector fields. We introduce a new version of vector inflation where the vector field has no potential term but is non-minimally coupled to gravity through the kinetic term. The non-minimal coupling is established by introducing the Einstein tensor besides the metric tensor within the kinetic term of the vector field. |
0812.4208 | Eliu Huerta | E. A. Huerta, Jonathan R. Gair | Influence of conservative corrections on parameter estimation for
extreme-mass-ratio inspirals | 28 pages, 9 figures, accepted for publication in Phys Rev D; v3
includes corrections to self-force results described in published erratum | Phys.Rev.D79:084021,2009; Erratum-ibid.D84:049903,2011 | 10.1103/PhysRevD.79.084021 10.1103/PhysRevD.84.049903 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an improved numerical kludge waveform model for circular,
equatorial EMRIs. The model is based on true Kerr geodesics, augmented by
radiative self-force corrections derived from perturbative calculations, and in
this paper for the first time we include conservative self-force corrections
that we derive by comparison to post-Newtonian results. We present results of a
Monte Carlo simulation of parameter estimation errors computed using the Fisher
Matrix and also assess the theoretical errors that would arise form omitting
the conservative correction terms we include here. We present results for three
different types of system, namely the inspirals of black holes, neutron stars
or white dwarfs into a supermassive black hole (SMBH). The analysis shows that
for a typical source (a 10 solar mass compact object captured by a one million
solar mass SMBH at signal to noise ratio of 30) we expect to determine the two
masses to within a fractional error of ~0.0001, measure the spin parameter q to
~0.00003 and determine the location of the source on the sky and the spin
orientation to within 0.001 steradians. We show that, for this kludge model,
omitting the conservative corrections leads to a small error over much of the
parameter space, i.e., the ratio R of the theoretical model error to the Fisher
Matrix error is R<1 for all ten parameters in the model. For the few systems
with larger errors typically R<3 and hence the conservative corrections can be
marginally ignored. In addition, we use our model and first order self-force
results for Schwarzschild black holes to estimate the error that arises from
omitting the second-order radiative piece of the self-force. This indicates
that it may not be necessary to go beyond first order to recover accurate
parameter estimates.
| [
{
"created": "Mon, 22 Dec 2008 14:58:36 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Apr 2009 17:12:20 GMT",
"version": "v2"
},
{
"created": "Tue, 20 Sep 2011 18:07:02 GMT",
"version": "v3"
},
{
"created": "Wed, 21 Sep 2011 18:32:34 GMT",
"version": "v4"
}
] | 2011-09-22 | [
[
"Huerta",
"E. A.",
""
],
[
"Gair",
"Jonathan R.",
""
]
] | We present an improved numerical kludge waveform model for circular, equatorial EMRIs. The model is based on true Kerr geodesics, augmented by radiative self-force corrections derived from perturbative calculations, and in this paper for the first time we include conservative self-force corrections that we derive by comparison to post-Newtonian results. We present results of a Monte Carlo simulation of parameter estimation errors computed using the Fisher Matrix and also assess the theoretical errors that would arise form omitting the conservative correction terms we include here. We present results for three different types of system, namely the inspirals of black holes, neutron stars or white dwarfs into a supermassive black hole (SMBH). The analysis shows that for a typical source (a 10 solar mass compact object captured by a one million solar mass SMBH at signal to noise ratio of 30) we expect to determine the two masses to within a fractional error of ~0.0001, measure the spin parameter q to ~0.00003 and determine the location of the source on the sky and the spin orientation to within 0.001 steradians. We show that, for this kludge model, omitting the conservative corrections leads to a small error over much of the parameter space, i.e., the ratio R of the theoretical model error to the Fisher Matrix error is R<1 for all ten parameters in the model. For the few systems with larger errors typically R<3 and hence the conservative corrections can be marginally ignored. In addition, we use our model and first order self-force results for Schwarzschild black holes to estimate the error that arises from omitting the second-order radiative piece of the self-force. This indicates that it may not be necessary to go beyond first order to recover accurate parameter estimates. |
2208.03723 | Rong-Jia Yang | Tong-Yu He, Ziqiang Cai, Rong-Jia Yang | Thin accretion disks around a black hole in Einstein-Aether-scalar
theory | 9 pages, 6 figures, 1 table, some errors are corrected | Eur. Phys. J. C 82, 1067 (2022) | 10.1140/epjc/s10052-022-11037-x | null | gr-qc astro-ph.HE hep-th | http://creativecommons.org/licenses/by-nc-sa/4.0/ | We consider the accretion process in the thin disk around a supermassive
black hole in Einstein-aether-scalar theory. We probe the effects of the model
parameter on the physical properties of the disk. The results show that with
increasing value of the parameter, the energy flux, the radiation temperature,
the spectra cut-off frequency, the spectra luminosity, and the conversion
efficiency of the disk decrease. The disk is hotter and more luminous than that
in general relativity for negative parameter, while it is cooler and less
luminous for positive parameter. We also find some values of the parameter
allowed by the theory are excluded by the physical properties of the disk.
| [
{
"created": "Sun, 7 Aug 2022 13:50:01 GMT",
"version": "v1"
},
{
"created": "Sun, 27 Nov 2022 13:44:25 GMT",
"version": "v2"
}
] | 2022-11-29 | [
[
"He",
"Tong-Yu",
""
],
[
"Cai",
"Ziqiang",
""
],
[
"Yang",
"Rong-Jia",
""
]
] | We consider the accretion process in the thin disk around a supermassive black hole in Einstein-aether-scalar theory. We probe the effects of the model parameter on the physical properties of the disk. The results show that with increasing value of the parameter, the energy flux, the radiation temperature, the spectra cut-off frequency, the spectra luminosity, and the conversion efficiency of the disk decrease. The disk is hotter and more luminous than that in general relativity for negative parameter, while it is cooler and less luminous for positive parameter. We also find some values of the parameter allowed by the theory are excluded by the physical properties of the disk. |
1912.08607 | Micha{\l} Eckstein | Erik Aurell, Micha{\l} Eckstein, Pawe{\l} Horodecki | Quantum black holes as solvents | 8 pages, 1 figure. Version published in FoP | Found. Phys. 51, 54 (2021) | 10.1007/s10701-021-00456-7 | null | gr-qc hep-th quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Almost all of the entropy in the universe is in the form of
Bekenstein--Hawking (BH) entropy of super-massive black holes. This entropy, if
it satisfies Boltzmann's equation $S=\log{\cal N}$, hence represents almost all
the accessible phase space of the Universe, somehow associated to objects which
themselves fill out a very small fraction of ordinary three-dimensional space.
Although time scales are very long, it is believed that black holes will
eventually evaporate by emitting Hawking radiation, which is thermal when
counted mode by mode. A pure quantum state collapsing to a black hole will
hence eventually re-emerge as a state with strictly positive entropy, which
constitutes the famous black hole information paradox. Expanding on a remark by
Hawking we posit that BH entropy is a thermodynamic entropy, which must be
distinguished from information-theoretic entropy. The paradox can then be
explained by information return in Hawking radiation. The novel perspective
advanced here is that if BH entropy counts the number of accessible physical
states in a quantum black hole, then the paradox can be seen as an instance of
the fundamental problem of statistical mechanics. We suggest a specific analogy
to the increase of the entropy in a solvation process. We further show that the
huge phase volume (${\cal N}$), which must be made available to the universe in
a gravitational collapse, cannot originate from the entanglement between
ordinary matter and/or radiation inside and outside the black hole. We argue
that, instead, the quantum degrees of freedom of the gravitational field must
get activated near the singularity, resulting in a final state of the
`entangled entanglement' form involving both matter and gravity.
| [
{
"created": "Wed, 18 Dec 2019 13:49:54 GMT",
"version": "v1"
},
{
"created": "Mon, 17 May 2021 15:33:35 GMT",
"version": "v2"
}
] | 2021-05-18 | [
[
"Aurell",
"Erik",
""
],
[
"Eckstein",
"Michał",
""
],
[
"Horodecki",
"Paweł",
""
]
] | Almost all of the entropy in the universe is in the form of Bekenstein--Hawking (BH) entropy of super-massive black holes. This entropy, if it satisfies Boltzmann's equation $S=\log{\cal N}$, hence represents almost all the accessible phase space of the Universe, somehow associated to objects which themselves fill out a very small fraction of ordinary three-dimensional space. Although time scales are very long, it is believed that black holes will eventually evaporate by emitting Hawking radiation, which is thermal when counted mode by mode. A pure quantum state collapsing to a black hole will hence eventually re-emerge as a state with strictly positive entropy, which constitutes the famous black hole information paradox. Expanding on a remark by Hawking we posit that BH entropy is a thermodynamic entropy, which must be distinguished from information-theoretic entropy. The paradox can then be explained by information return in Hawking radiation. The novel perspective advanced here is that if BH entropy counts the number of accessible physical states in a quantum black hole, then the paradox can be seen as an instance of the fundamental problem of statistical mechanics. We suggest a specific analogy to the increase of the entropy in a solvation process. We further show that the huge phase volume (${\cal N}$), which must be made available to the universe in a gravitational collapse, cannot originate from the entanglement between ordinary matter and/or radiation inside and outside the black hole. We argue that, instead, the quantum degrees of freedom of the gravitational field must get activated near the singularity, resulting in a final state of the `entangled entanglement' form involving both matter and gravity. |
2304.05209 | Muzaffer Adak | Muzaffer Adak, Nese Ozdemir, Caglar Pala | Weyl-Lorentz-U(1)-invariant symmetric teleparallel gravity in three
dimensions | To appear in EPJC | Eur. Phys. J. C 83 (2023) 606 | 10.1140/epjc/s10052-023-11771-w | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a Weyl-Lorentz-$U(1)$-invariant gravity model written in terms of
a scalar field, electromagnetic field and nonmetricity without torsion and
curvature, the so-called symmetric teleparallel geometry, in three dimensions.
Firstly, we obtain variational field equations from a Lagrangian. Then, we find
some classes of circularly symmetric rotating solutions by making only a metric
ansatz. The coincident gauge of symmetric teleparallel spacetime allows us for
doing so.
| [
{
"created": "Tue, 11 Apr 2023 13:19:23 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Jun 2023 21:47:31 GMT",
"version": "v2"
}
] | 2023-07-14 | [
[
"Adak",
"Muzaffer",
""
],
[
"Ozdemir",
"Nese",
""
],
[
"Pala",
"Caglar",
""
]
] | We consider a Weyl-Lorentz-$U(1)$-invariant gravity model written in terms of a scalar field, electromagnetic field and nonmetricity without torsion and curvature, the so-called symmetric teleparallel geometry, in three dimensions. Firstly, we obtain variational field equations from a Lagrangian. Then, we find some classes of circularly symmetric rotating solutions by making only a metric ansatz. The coincident gauge of symmetric teleparallel spacetime allows us for doing so. |
gr-qc/0107022 | Michael Martin Nieto | John D. Anderson, Eunice L. Lau, Slava G. Turyshev, Philip A. Laing,
and Michael Martin Nieto | Search for a Standard Explanation of the Pioneer Anomaly | Changes made for publication | Mod.Phys.Lett. A17 (2002) 875-886 | 10.1142/S0217732302007107 | LA-UR-01-3512 | gr-qc | null | The data from Pioneer 10 and 11 shows an anomalous, constant, Doppler
frequency drift that can be interpreted as an acceleration directed towards the
Sun of a_P = (8.74 \pm 1.33) x 10^{-8} cm/s^2. Although one can consider a new
physical origin for the anomaly, one first must investigate the contributions
of the prime candidates, which are systematics generated on board. Here we
expand upon previous analyses of thermal systematics. We demonstrate that
thermal models put forth so far are not supported by the analyzed data.
Possible ways to further investigate the nature of the anomaly are proposed.
| [
{
"created": "Thu, 5 Jul 2001 22:52:47 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jan 2002 05:09:15 GMT",
"version": "v2"
},
{
"created": "Wed, 12 Jun 2002 21:57:58 GMT",
"version": "v3"
}
] | 2016-12-21 | [
[
"Anderson",
"John D.",
""
],
[
"Lau",
"Eunice L.",
""
],
[
"Turyshev",
"Slava G.",
""
],
[
"Laing",
"Philip A.",
""
],
[
"Nieto",
"Michael Martin",
""
]
] | The data from Pioneer 10 and 11 shows an anomalous, constant, Doppler frequency drift that can be interpreted as an acceleration directed towards the Sun of a_P = (8.74 \pm 1.33) x 10^{-8} cm/s^2. Although one can consider a new physical origin for the anomaly, one first must investigate the contributions of the prime candidates, which are systematics generated on board. Here we expand upon previous analyses of thermal systematics. We demonstrate that thermal models put forth so far are not supported by the analyzed data. Possible ways to further investigate the nature of the anomaly are proposed. |
gr-qc/0510014 | Muxin Han | Muxin Han, Yongge Ma | Master Constraint Operator in Loop Quantum Gravity | 11 pages, significant modification in section 2, accepted for
publication in Phys. Lett. B | Phys.Lett.B635:225-231,2006 | 10.1016/j.physletb.2006.03.004 | null | gr-qc math-ph math.MP | null | We introduce a master constraint operator $\hat{\mathbf{M}}$ densely defined
in the diffeomorphism invariant Hilbert space in loop quantum gravity, which
corresponds classically to the master constraint in the programme. It is shown
that $\hat{\mathbf{M}}$ is positive and symmetric, and hence has its Friedrichs
self-adjoint extension. The same conclusion is tenable for an alternative
master operator $\hat{\mathbf{M'}}$, whose quadratic form coincides with the
one proposed by Thiemann. So the master constraint programme for loop quantum
gravity can be carried out in principle by employing either of the two
operators.
| [
{
"created": "Tue, 4 Oct 2005 16:43:12 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Oct 2005 01:03:57 GMT",
"version": "v2"
},
{
"created": "Fri, 4 Nov 2005 05:41:19 GMT",
"version": "v3"
},
{
"created": "Fri, 3 Mar 2006 15:25:11 GMT",
"version": "v4"
}
] | 2014-11-17 | [
[
"Han",
"Muxin",
""
],
[
"Ma",
"Yongge",
""
]
] | We introduce a master constraint operator $\hat{\mathbf{M}}$ densely defined in the diffeomorphism invariant Hilbert space in loop quantum gravity, which corresponds classically to the master constraint in the programme. It is shown that $\hat{\mathbf{M}}$ is positive and symmetric, and hence has its Friedrichs self-adjoint extension. The same conclusion is tenable for an alternative master operator $\hat{\mathbf{M'}}$, whose quadratic form coincides with the one proposed by Thiemann. So the master constraint programme for loop quantum gravity can be carried out in principle by employing either of the two operators. |
1304.1434 | Jos\'e Cleriston Campos de Souza | J. C. C. de Souza and M. O. C. Pires | Domain Wall Model in the Galactic Bose-Einstein Condensate Halo | 11 pages; 6 figures; v.2: 12 pages, matches published version in JCAP | null | 10.1088/1475-7516/2013/05/027 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We assume that the galactical dark matter halo, considered composed of an
axionlike particles Bose-Einstein condensate \cite{pir12}, can present
topological defects, namely domain walls, arising as the dark soliton solution
for the Gross-Pitaevskii equation in a self-graviting potential. We investigate
the influence that such substructures would have in the gravitational
interactions within a galaxy. We find that, for the simple domain wall model
proposed, the effects are too small to be identified, either by means of a
local measurement of the gradient of the gravitational field or by analysing
galaxy rotation curves. In the first case, the gradient of the gravitational
field in the vicinity of the domain wall would be $10^{-31}\; (m/s^2)/m$. In
the second case, the ratio of the tangential velocity correction of a star due
to the presence of the domain wall to the velocity in the spherical symmetric
case would be $10^{-8}$.
| [
{
"created": "Thu, 4 Apr 2013 17:16:10 GMT",
"version": "v1"
},
{
"created": "Wed, 22 May 2013 13:41:09 GMT",
"version": "v2"
}
] | 2013-05-23 | [
[
"de Souza",
"J. C. C.",
""
],
[
"Pires",
"M. O. C.",
""
]
] | We assume that the galactical dark matter halo, considered composed of an axionlike particles Bose-Einstein condensate \cite{pir12}, can present topological defects, namely domain walls, arising as the dark soliton solution for the Gross-Pitaevskii equation in a self-graviting potential. We investigate the influence that such substructures would have in the gravitational interactions within a galaxy. We find that, for the simple domain wall model proposed, the effects are too small to be identified, either by means of a local measurement of the gradient of the gravitational field or by analysing galaxy rotation curves. In the first case, the gradient of the gravitational field in the vicinity of the domain wall would be $10^{-31}\; (m/s^2)/m$. In the second case, the ratio of the tangential velocity correction of a star due to the presence of the domain wall to the velocity in the spherical symmetric case would be $10^{-8}$. |
gr-qc/0202018 | Patrizia Vitale | Gaetano Vilasi and Patrizia Vitale | On the SO(2,1) symmetry in General Relativity | 10 pages, latex, no figures | Class.Quant.Grav. 19 (2002) 3333-3340 | 10.1088/0264-9381/19/12/315 | ESI-1110 | gr-qc | null | The role of the SO(2,1) symmetry in General Relativity is analyzed.
Cosmological solutions of Einstein field equations invariant with respect to a
space-like Lie algebra G_r, with r between 3 and 6 and containing so(2,1) as a
subalgebra, are also classified.
| [
{
"created": "Wed, 6 Feb 2002 11:42:30 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Vilasi",
"Gaetano",
""
],
[
"Vitale",
"Patrizia",
""
]
] | The role of the SO(2,1) symmetry in General Relativity is analyzed. Cosmological solutions of Einstein field equations invariant with respect to a space-like Lie algebra G_r, with r between 3 and 6 and containing so(2,1) as a subalgebra, are also classified. |
gr-qc/0105078 | Daniel Grumiller | D. Grumiller | Quantum Dilaton Gravity in Two Dimensions with Matter | 7 figures, 173 pages, PhD thesis TU-Vienna (advisor: Wolfgang
Kummer), v2: shortened abstract, corrected typos, added references, v3:
corrected typos (*sigh*), updated references, v4: yes, still some typos;
awarded with the Austrian Victor-Hess prize 2003 | null | null | null | gr-qc hep-th | null | In this thesis special emphasis is put on the quantization of the spherically
reduced Einstein-massless-Klein-Gordon model using a first order approach for
geometric quantities, because phenomenologically it is probably the most
relevant of all dilaton models with matter. After a Hamiltonian BRST analysis
path integral quantization is performed using temporal gauge for the Cartan
variables. Retrospectively, the simpler Faddeev-Popov approach turns out to be
sufficient. It is possible to eliminate all unphysical and geometric quantities
establishing a non-local and non-polynomial action depending solely on the
scalar field and on some integration constants, fixed by suitable boundary
conditions on the asymptotic effective line element.
Then, attention is turned to the evaluation of the (two) lowest order tree
vertices, explicitly assuming a perturbative expansion in the scalar field
being valid. Each of them diverges, but unexpected cancellations yield a finite
S-matrix element when both contributions are summed. The phenomenon of a
"virtual black hole" -- already encountered in the simpler case of minimally
coupled scalars in two dimensions -- occurs, as the study of the (matter
dependent) metric reveals. A discussion of the scattering amplitude leads to
the prediction of gravitational decay of spherical waves, a novel physical
phenomenon. Several possible extensions conclude this dissertation.
| [
{
"created": "Mon, 21 May 2001 18:56:16 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Jun 2001 15:49:21 GMT",
"version": "v2"
},
{
"created": "Thu, 15 Nov 2001 09:21:48 GMT",
"version": "v3"
},
{
"created": "Tue, 20 May 2003 14:39:02 GMT",
"version": "v4"
}
] | 2007-05-23 | [
[
"Grumiller",
"D.",
""
]
] | In this thesis special emphasis is put on the quantization of the spherically reduced Einstein-massless-Klein-Gordon model using a first order approach for geometric quantities, because phenomenologically it is probably the most relevant of all dilaton models with matter. After a Hamiltonian BRST analysis path integral quantization is performed using temporal gauge for the Cartan variables. Retrospectively, the simpler Faddeev-Popov approach turns out to be sufficient. It is possible to eliminate all unphysical and geometric quantities establishing a non-local and non-polynomial action depending solely on the scalar field and on some integration constants, fixed by suitable boundary conditions on the asymptotic effective line element. Then, attention is turned to the evaluation of the (two) lowest order tree vertices, explicitly assuming a perturbative expansion in the scalar field being valid. Each of them diverges, but unexpected cancellations yield a finite S-matrix element when both contributions are summed. The phenomenon of a "virtual black hole" -- already encountered in the simpler case of minimally coupled scalars in two dimensions -- occurs, as the study of the (matter dependent) metric reveals. A discussion of the scattering amplitude leads to the prediction of gravitational decay of spherical waves, a novel physical phenomenon. Several possible extensions conclude this dissertation. |
1002.3600 | Kayll Lake | Kayll Lake | Some notes on the Kruskal - Szekeres completion | One typo corrected | Class. Quantum Grav. 27 097001 2010 | 10.1088/0264-9381/27/9/097001 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Kruskal - Szekeres (KS) completion of the Schwarzschild spacetime is open
to Synge's methodological criticism that the KS procedure generates "good"
coordinates from "bad". This is addressed here in two ways: First I generate
the KS coordinates from Israel coordinates, which are also "good", and then I
generate the KS coordinates directly from a streamlined integration of the
Einstein equations.
| [
{
"created": "Thu, 18 Feb 2010 20:12:17 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Mar 2010 17:40:43 GMT",
"version": "v2"
},
{
"created": "Wed, 12 May 2010 12:49:19 GMT",
"version": "v3"
}
] | 2015-05-18 | [
[
"Lake",
"Kayll",
""
]
] | The Kruskal - Szekeres (KS) completion of the Schwarzschild spacetime is open to Synge's methodological criticism that the KS procedure generates "good" coordinates from "bad". This is addressed here in two ways: First I generate the KS coordinates from Israel coordinates, which are also "good", and then I generate the KS coordinates directly from a streamlined integration of the Einstein equations. |
2310.01249 | Lijing Shao | Jierui Hu, Dicong Liang, Lijing Shao | Probing nontensorial gravitational waves with a next-generation
ground-based detector network | 10 pages, 4 figures; accepted by PRD | Phys. Rev. D 109 (2024) 084023 | 10.1103/PhysRevD.109.084023 | ET-0314A-23 | gr-qc astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | In General Relativity, there are only two polarizations for gravitational
waves. However, up to six polarizations are possible in a generic metric theory
of gravity. Therefore, measuring the polarization content of gravitational
waves provides an efficient way to test theories of gravity. We analyze the
sensitivity of a next-generation ground-based detector network to nontensorial
polarizations. We present our method to localize GW signals in the
time-frequency domain and construct the model-independent null stream for
events with known sky locations. We obtain results based on simulations of
binary neutron star mergers in a six-detector network. For a single event at a
luminosity distance $D_L=100 \, {\rm Mpc}$, at $5\sigma$ confidence, the
smallest amplitude for detection of scalar and vector modes relative to tensor
modes are respectively $A_{s}=0.045 $ and $A_{v}=0.014 $. For multiple events
in an averaged observing run of 10 years, the detection limits at $5\sigma$
confidence are $A_s=0.05$ and $A_v=0.02$. If we are fortunate, a few strong
events might significantly improve the limits.
| [
{
"created": "Mon, 2 Oct 2023 14:32:36 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Mar 2024 01:40:49 GMT",
"version": "v2"
}
] | 2024-04-12 | [
[
"Hu",
"Jierui",
""
],
[
"Liang",
"Dicong",
""
],
[
"Shao",
"Lijing",
""
]
] | In General Relativity, there are only two polarizations for gravitational waves. However, up to six polarizations are possible in a generic metric theory of gravity. Therefore, measuring the polarization content of gravitational waves provides an efficient way to test theories of gravity. We analyze the sensitivity of a next-generation ground-based detector network to nontensorial polarizations. We present our method to localize GW signals in the time-frequency domain and construct the model-independent null stream for events with known sky locations. We obtain results based on simulations of binary neutron star mergers in a six-detector network. For a single event at a luminosity distance $D_L=100 \, {\rm Mpc}$, at $5\sigma$ confidence, the smallest amplitude for detection of scalar and vector modes relative to tensor modes are respectively $A_{s}=0.045 $ and $A_{v}=0.014 $. For multiple events in an averaged observing run of 10 years, the detection limits at $5\sigma$ confidence are $A_s=0.05$ and $A_v=0.02$. If we are fortunate, a few strong events might significantly improve the limits. |
1301.1411 | Sunil Maharaj | M. C. Kweyama, K. S. Govinder, S. D. Maharaj | A fifth order differential equation for charged perfect fluids | 17 pages, To appear in J. Math. Phys | J. Math. Phys. 53: 033707, 2012 | 10.1063/1.3694279 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the master nonlinear partial differential equation that
governs the evolution of shear-free spherically symmetric charged fluids. We
use an approach which has not been considered previously for the underlying
equation in shear-free spherically symmetric spacetimes. We derive a fifth
order purely differential equation that must be satisfied for the underlying
equation to admit a Lie point symmetry. We then perform a comprehensive
analysis of this equation utilising the Lie symmetry analysis and direct
integration. This enables us to reduce the fifth order equation to quadratures.
Earlier results are shown to be contained in our general treatment.
| [
{
"created": "Tue, 8 Jan 2013 04:46:54 GMT",
"version": "v1"
}
] | 2015-06-12 | [
[
"Kweyama",
"M. C.",
""
],
[
"Govinder",
"K. S.",
""
],
[
"Maharaj",
"S. D.",
""
]
] | We investigate the master nonlinear partial differential equation that governs the evolution of shear-free spherically symmetric charged fluids. We use an approach which has not been considered previously for the underlying equation in shear-free spherically symmetric spacetimes. We derive a fifth order purely differential equation that must be satisfied for the underlying equation to admit a Lie point symmetry. We then perform a comprehensive analysis of this equation utilising the Lie symmetry analysis and direct integration. This enables us to reduce the fifth order equation to quadratures. Earlier results are shown to be contained in our general treatment. |
2310.06607 | Yu Gao | Yu Gao, Huaqiao Zhang and Wei Xu | A M\"ossbauer Scheme to Probe Gravitational Waves | 11 pages, 5 figures, 2 tables | Science Bulletin, 2024 | 10.1016/j.scib.2024.07.038 | null | gr-qc astro-ph.IM nucl-ex | http://creativecommons.org/licenses/by/4.0/ | Under the local gravitational field, perturbations from high-frequency
gravitational waves can cause a vertical shift of the M\"ossbauer resonance
height. Considering a stationary scheme with the $^{109}$Ag isotope, we
demonstrate that the extremely high precision of M\"ossbauer resonance allows
for competitive gravitational wave sensitivity from KHz up to above MHz
frequencies. M\"ossbauer resonance can offer a novel and small-sized
alternative in the quest of multi-band gravitational wave searches. The
presence of the static gravitational field plays essential role in the
detection mechanism, isotope selection and sensitivity forecast. The proposed
stationary scheme's sensitivity has the potential of significant improvement in
a low-gravity environment.
| [
{
"created": "Tue, 10 Oct 2023 13:14:54 GMT",
"version": "v1"
}
] | 2024-08-13 | [
[
"Gao",
"Yu",
""
],
[
"Zhang",
"Huaqiao",
""
],
[
"Xu",
"Wei",
""
]
] | Under the local gravitational field, perturbations from high-frequency gravitational waves can cause a vertical shift of the M\"ossbauer resonance height. Considering a stationary scheme with the $^{109}$Ag isotope, we demonstrate that the extremely high precision of M\"ossbauer resonance allows for competitive gravitational wave sensitivity from KHz up to above MHz frequencies. M\"ossbauer resonance can offer a novel and small-sized alternative in the quest of multi-band gravitational wave searches. The presence of the static gravitational field plays essential role in the detection mechanism, isotope selection and sensitivity forecast. The proposed stationary scheme's sensitivity has the potential of significant improvement in a low-gravity environment. |
2202.12735 | Henri Inchausp\'e Dr. | Henri Inchausp\'e, Martin Hewitson, Orion Sauter, Peter Wass | New LISA dynamics feedback control scheme: Common-mode isolation of test
mass control and probes of test-mass acceleration | 17 pages, 9 figures | Phys. Rev. D 106, 022006 (2022) | 10.1103/PhysRevD.106.022006 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Drag-Free and Attitude Control System is a central element of LISA
technology, ensuring the very high dynamic stability of spacecraft and test
masses required in order to reach the sensitivity that gravitational wave
astronomy in space requires. Applying electrostatic forces on test-masses is
unavoidable but should be restricted to the minimum necessary to keep the
spacecraft-test masses system in place, while granting the optimal quality of
test-mass free-fall. To realise this, we propose a new test-mass suspension
scheme that applies forces and torques only in proportion to any differential
test mass motion observed, and we demonstrate that the new scheme significantly
mitigates the amount of suspension forces and torques needed to control the
whole system. The mathematical method involved allows us to derive a new
observable measuring the differential acceleration of test masses projected on
the relevant sensitive axes, which will have important consequences for LISA
data calibration, processing and analysis.
| [
{
"created": "Fri, 25 Feb 2022 14:49:34 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Aug 2022 15:25:49 GMT",
"version": "v2"
}
] | 2022-08-18 | [
[
"Inchauspé",
"Henri",
""
],
[
"Hewitson",
"Martin",
""
],
[
"Sauter",
"Orion",
""
],
[
"Wass",
"Peter",
""
]
] | The Drag-Free and Attitude Control System is a central element of LISA technology, ensuring the very high dynamic stability of spacecraft and test masses required in order to reach the sensitivity that gravitational wave astronomy in space requires. Applying electrostatic forces on test-masses is unavoidable but should be restricted to the minimum necessary to keep the spacecraft-test masses system in place, while granting the optimal quality of test-mass free-fall. To realise this, we propose a new test-mass suspension scheme that applies forces and torques only in proportion to any differential test mass motion observed, and we demonstrate that the new scheme significantly mitigates the amount of suspension forces and torques needed to control the whole system. The mathematical method involved allows us to derive a new observable measuring the differential acceleration of test masses projected on the relevant sensitive axes, which will have important consequences for LISA data calibration, processing and analysis. |
1403.5160 | Mengjie Wang | Mengjie Wang, Carlos Herdeiro | Superradiant instabilities in a $D$-dimensional small
Reissner-Nordstr\"om-Anti-de Sitter black hole | 8 pages, to appear in PRD(2014) | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the superradiant instability for a charged scalar field in a
$D$-dimensional small Reissner-Nordstr\"om-Anti-de Sitter (RN-AdS) black hole.
Firstly, we solve the charged Klein-Gordon equation analytically by a matching
method. We show that the general $D$-dimensional quasinormal frequencies depend
on the relation between the angular momentum quantum number, $\ell$, and $D$.
When $\ell$ is a (non-negative) integer multiple of $D-3$, i.e $\ell=p(D-3)$,
we find an analytical quasinormal frequency formula adding a purely imaginary
correction to the AdS normal frequencies. This is the case for all $\ell$ modes
in $D=4$. For general $D$ there are two more cases: i) when $\ell$ obeys
$\ell=(p+\frac{1}{2})(D-3)$, which can occur for odd $D$, we observe that the
matching method fails, since the near and far region solutions have different
functional dependences; ii) for all other cases, the analytical quasinormal
frequency formula gives a complex correction to the AdS normal frequencies.
Secondly, we perform a numerical calculation which confirms the analytical
formulas obtained with the matching method and allows us to explore the case
where that method failed. In the latter case, as in the former, we verify that
all $\ell$ modes for all $D$ may become superradiant, which contradicts a
previous claim in the literature.
| [
{
"created": "Thu, 20 Mar 2014 14:58:27 GMT",
"version": "v1"
}
] | 2014-03-24 | [
[
"Wang",
"Mengjie",
""
],
[
"Herdeiro",
"Carlos",
""
]
] | We investigate the superradiant instability for a charged scalar field in a $D$-dimensional small Reissner-Nordstr\"om-Anti-de Sitter (RN-AdS) black hole. Firstly, we solve the charged Klein-Gordon equation analytically by a matching method. We show that the general $D$-dimensional quasinormal frequencies depend on the relation between the angular momentum quantum number, $\ell$, and $D$. When $\ell$ is a (non-negative) integer multiple of $D-3$, i.e $\ell=p(D-3)$, we find an analytical quasinormal frequency formula adding a purely imaginary correction to the AdS normal frequencies. This is the case for all $\ell$ modes in $D=4$. For general $D$ there are two more cases: i) when $\ell$ obeys $\ell=(p+\frac{1}{2})(D-3)$, which can occur for odd $D$, we observe that the matching method fails, since the near and far region solutions have different functional dependences; ii) for all other cases, the analytical quasinormal frequency formula gives a complex correction to the AdS normal frequencies. Secondly, we perform a numerical calculation which confirms the analytical formulas obtained with the matching method and allows us to explore the case where that method failed. In the latter case, as in the former, we verify that all $\ell$ modes for all $D$ may become superradiant, which contradicts a previous claim in the literature. |
1703.08168 | Philippe Landry | Philippe Landry | Tidal deformation of a slowly rotating material body: Interior metric
and Love numbers | 19 pages, 7 figures; updated figures and corrected typos; matches the
published version | Phys. Rev. D 95, 124058 (2017) | 10.1103/PhysRevD.95.124058 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The metric outside a compact body deformed by a quadrupolar tidal field is
universal up to its Love numbers, constants which encode the tidal response's
dependence on the body's internal structure. For a non-rotating body, the
deformed external geometry is characterized by the familiar gravitational Love
numbers $K_2^{\text{el}}$ and $K_2^{\text{mag}}$. For a slowly rotating body,
these must be supplemented by rotational-tidal Love numbers, which measure the
response to couplings between the body's spin and the external tidal field. By
integrating the interior field equations, I find that the response of a
barotropic perfect fluid to spin-coupled tidal perturbations is described by
two rotational-tidal Love numbers, which I calculate explicitly for polytropes.
Two other rotational-tidal Love numbers identified in prior work are found to
have a fixed, universal value for all barotropes. Equipped with the complete
interior solution, I calculate the amplitude of the time-varying internal
currents induced by the gravitomagnetic part of the tidal field. For a typical
neutron star in an equal-mass binary system, the size of the equatorial
velocity perturbation is on the order of kilometers per second.
| [
{
"created": "Thu, 23 Mar 2017 17:56:14 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Jul 2017 16:53:07 GMT",
"version": "v2"
}
] | 2017-07-05 | [
[
"Landry",
"Philippe",
""
]
] | The metric outside a compact body deformed by a quadrupolar tidal field is universal up to its Love numbers, constants which encode the tidal response's dependence on the body's internal structure. For a non-rotating body, the deformed external geometry is characterized by the familiar gravitational Love numbers $K_2^{\text{el}}$ and $K_2^{\text{mag}}$. For a slowly rotating body, these must be supplemented by rotational-tidal Love numbers, which measure the response to couplings between the body's spin and the external tidal field. By integrating the interior field equations, I find that the response of a barotropic perfect fluid to spin-coupled tidal perturbations is described by two rotational-tidal Love numbers, which I calculate explicitly for polytropes. Two other rotational-tidal Love numbers identified in prior work are found to have a fixed, universal value for all barotropes. Equipped with the complete interior solution, I calculate the amplitude of the time-varying internal currents induced by the gravitomagnetic part of the tidal field. For a typical neutron star in an equal-mass binary system, the size of the equatorial velocity perturbation is on the order of kilometers per second. |
2003.10781 | Jonas Pereira | Jonas P. Pereira, Micha{\l} Bejger, Nils Andersson, Fabian Gittins | Tidal deformations of hybrid stars with sharp phase transitions and
elastic crusts | 11 pages, 3 figures. Minor changes to the abstract. Accepted for
publication in ApJ | null | 10.3847/1538-4357/ab8aca | null | gr-qc astro-ph.HE astro-ph.SR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Gravitational wave astronomy is expected to provide independent constraints
on neutron star properties, such as their dense matter equation of state. This
is possible with the measurements of binary components' tidal deformability,
which alter the point-particle gravitational waveforms of the late inspiral
phase of neutron-star binaries. Although current gravitational wave detectors
are not sensitive enough for a precise determination of the individual tidal
deformations of the components, a large number of combined observations with
future detectors will decrease uncertainties in this quantity. Here we provide
a first study of the tidal deformability effects due to the elasticity/solidity
of the crust (hadronic phase) in a hybrid neutron star, as well as the
influence of a quark-hadronic phase density jump on tidal deformations. We
employ the framework of nonradial perturbations with zero frequency and study
hadronic phases presenting elastic aspects when perturbed (with the shear
modulus approximately $1\%$ of the pressure). We find that the relative tidal
deformation change in a hybrid star with a perfect-fluid quark phase and a
hadronic phase presenting an elastic part is never larger than about $2-4\%$
(with respect to a perfect-fluid counterpart). These maximum changes occur when
the elastic region of a hybrid star is larger than approximately $60\%$ of the
star's radius, which may happen when its quark phase is small and the density
jump is large enough, or even when a hybrid star has an elastic mixed phase.
For other cases, the relative tidal deformation changes due to an elastic crust
are negligible ($10^{-5}-10^{-1}\%$), therefore unlikely to be measured even
with third generation detectors. Thus, only when the size of the elastic
hadronic region of a hybrid star is over half of its radius, the effects of
elasticity could have a noticeable impact on tidal deformations.
| [
{
"created": "Tue, 24 Mar 2020 11:29:05 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Apr 2020 09:25:00 GMT",
"version": "v2"
}
] | 2020-05-27 | [
[
"Pereira",
"Jonas P.",
""
],
[
"Bejger",
"Michał",
""
],
[
"Andersson",
"Nils",
""
],
[
"Gittins",
"Fabian",
""
]
] | Gravitational wave astronomy is expected to provide independent constraints on neutron star properties, such as their dense matter equation of state. This is possible with the measurements of binary components' tidal deformability, which alter the point-particle gravitational waveforms of the late inspiral phase of neutron-star binaries. Although current gravitational wave detectors are not sensitive enough for a precise determination of the individual tidal deformations of the components, a large number of combined observations with future detectors will decrease uncertainties in this quantity. Here we provide a first study of the tidal deformability effects due to the elasticity/solidity of the crust (hadronic phase) in a hybrid neutron star, as well as the influence of a quark-hadronic phase density jump on tidal deformations. We employ the framework of nonradial perturbations with zero frequency and study hadronic phases presenting elastic aspects when perturbed (with the shear modulus approximately $1\%$ of the pressure). We find that the relative tidal deformation change in a hybrid star with a perfect-fluid quark phase and a hadronic phase presenting an elastic part is never larger than about $2-4\%$ (with respect to a perfect-fluid counterpart). These maximum changes occur when the elastic region of a hybrid star is larger than approximately $60\%$ of the star's radius, which may happen when its quark phase is small and the density jump is large enough, or even when a hybrid star has an elastic mixed phase. For other cases, the relative tidal deformation changes due to an elastic crust are negligible ($10^{-5}-10^{-1}\%$), therefore unlikely to be measured even with third generation detectors. Thus, only when the size of the elastic hadronic region of a hybrid star is over half of its radius, the effects of elasticity could have a noticeable impact on tidal deformations. |
1102.4578 | Stephen Castles | S. H. Castles | The SU(1,1)/U(1) dynamical symmetry of a family of particles in the
field of a Kerr black hole | 9 pages, 2 figures | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A family of particles moving within a cone centered on a Kerr black hole is
shown to have SU(1,1)/U(1) dynamical symmetry. This symmetry is used to
identify a global time variable shared by all particles in the family. With
this time variable, Hamilton's equations for the family of particles have the
canonical form of the harmonic oscillator. The SU(1,1)/U(1) dynamical symmetry,
along with the well defined global time variable and observer, assists in
determining the quantization of the motion.
| [
{
"created": "Tue, 22 Feb 2011 18:48:06 GMT",
"version": "v1"
}
] | 2011-02-23 | [
[
"Castles",
"S. H.",
""
]
] | A family of particles moving within a cone centered on a Kerr black hole is shown to have SU(1,1)/U(1) dynamical symmetry. This symmetry is used to identify a global time variable shared by all particles in the family. With this time variable, Hamilton's equations for the family of particles have the canonical form of the harmonic oscillator. The SU(1,1)/U(1) dynamical symmetry, along with the well defined global time variable and observer, assists in determining the quantization of the motion. |
2012.08151 | Guillem Dom\`enech | Guillem Dom\`enech, Chunshan Lin and Misao Sasaki | Gravitational wave constraints on the primordial black hole dominated
early universe | Revised version. Included suppression due to the finite duration of
black hole evaporation | null | 10.1088/1475-7516/2021/04/062 | YITP-20-156 | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the gravitational waves (GWs) induced by the density
fluctuations due to inhomogeneous distribution of primordial black holes (PBHs)
in the case where PBHs eventually dominate and reheat the universe by Hawking
evaporation. The initial PBH density fluctuations are isocurvature in nature.
We find that most of the induced GWs are generated right after evaporation,
when the universe transits from the PBH dominated era to the radiation
dominated era and the curvature perturbation starts to oscillate wildly. The
strongest constraint on the amount of the produced GWs comes from the big bang
nucleosynthesis (BBN). We improve previous constraints on the PBH fraction and
find that it cannot exceed $10^{-3}$. Furthermore, this maximum fraction
decreases as the mass increases and reaches $10^{-9}$ for $M_{\rm PBH}\sim
5\times10^8 {\rm g}$, which is the largest mass allowed by the BBN constraint
on the reheating temperature. Considering that PBH may cluster above a given
clustering scale, we also derive a lower bound on the scale of clustering.
Interestingly, the GW spectrum for $M_{\rm PBH}\sim 10^4 -10^8 {\rm g}$ enters
the observational window of LIGO and DECIGO and could be tested in the future.
Although we focus on the PBH dominated early universe in this paper, our
methodology is applicable to any model with early isocurvature perturbation.
| [
{
"created": "Tue, 15 Dec 2020 08:44:34 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Sep 2021 14:37:43 GMT",
"version": "v2"
}
] | 2021-09-14 | [
[
"Domènech",
"Guillem",
""
],
[
"Lin",
"Chunshan",
""
],
[
"Sasaki",
"Misao",
""
]
] | We calculate the gravitational waves (GWs) induced by the density fluctuations due to inhomogeneous distribution of primordial black holes (PBHs) in the case where PBHs eventually dominate and reheat the universe by Hawking evaporation. The initial PBH density fluctuations are isocurvature in nature. We find that most of the induced GWs are generated right after evaporation, when the universe transits from the PBH dominated era to the radiation dominated era and the curvature perturbation starts to oscillate wildly. The strongest constraint on the amount of the produced GWs comes from the big bang nucleosynthesis (BBN). We improve previous constraints on the PBH fraction and find that it cannot exceed $10^{-3}$. Furthermore, this maximum fraction decreases as the mass increases and reaches $10^{-9}$ for $M_{\rm PBH}\sim 5\times10^8 {\rm g}$, which is the largest mass allowed by the BBN constraint on the reheating temperature. Considering that PBH may cluster above a given clustering scale, we also derive a lower bound on the scale of clustering. Interestingly, the GW spectrum for $M_{\rm PBH}\sim 10^4 -10^8 {\rm g}$ enters the observational window of LIGO and DECIGO and could be tested in the future. Although we focus on the PBH dominated early universe in this paper, our methodology is applicable to any model with early isocurvature perturbation. |
1909.08562 | Zhen Zhong | Ming Zhang, Jie Jiang, Zhen Zhong | The fastest relaxation rate of higher-dimensional
Reissner--Nordstr\"{o}m black hole | PLB published version | Physics Letters B, Volume 798 (2019) 134959 | 10.1016/j.physletb.2019.134959 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the eikonal regime, we analytically calculate quasinormal resonance
frequencies for massless scalar perturbations of the higher-dimensional
Reissner--Nordstr\"{o}m (RN) black holes. Remarkably, we find that the
higher-dimensional RN black holes coupled with the massless scalar fields have
the fastest relaxation rates in the Schwarzschild limit, this is qualitatively
different from the four-dimensional case where the black hole with
non-vanishing charge has the fastest relaxation rate.
| [
{
"created": "Wed, 18 Sep 2019 16:34:06 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Oct 2019 08:32:27 GMT",
"version": "v2"
}
] | 2019-10-07 | [
[
"Zhang",
"Ming",
""
],
[
"Jiang",
"Jie",
""
],
[
"Zhong",
"Zhen",
""
]
] | In the eikonal regime, we analytically calculate quasinormal resonance frequencies for massless scalar perturbations of the higher-dimensional Reissner--Nordstr\"{o}m (RN) black holes. Remarkably, we find that the higher-dimensional RN black holes coupled with the massless scalar fields have the fastest relaxation rates in the Schwarzschild limit, this is qualitatively different from the four-dimensional case where the black hole with non-vanishing charge has the fastest relaxation rate. |
1808.05634 | Genly Le\'on | Genly Leon (Catolica del Norte U.), Andronikos Paliathanasis and Jorge
Luis Morales-Mart\'inez (Guanajuato U.) | The past and future dynamics of quintom dark energy models | 22 pages, 3 compound figures (13 eps files) | Eur. Phys. J. C (2018) 78:753 | 10.1140/epjc/s10052-018-6225-y | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the phase space of the quintom cosmologies for a class of
exponential potentials. We combine normal forms expansions and the center
manifold theory in order to describe the dynamics near equilibrium sets.
Furthermore, we construct the unstable and center manifold of the massless
scalar field cosmology motivated by the numerical results given in Lazkoz and
Leon (Phys Lett B 638:303. arXiv:astro-ph/0602590, 2006). We study the role of
the curvature on the dynamics. Several monotonic functions are defined on
relevant invariant sets for the quintom cosmology. Finally, conservation laws
of the cosmological field equations and algebraic solutions are determined by
using the symmetry analysis and the singularity analysis.
| [
{
"created": "Thu, 16 Aug 2018 18:26:01 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Sep 2018 16:59:05 GMT",
"version": "v2"
}
] | 2018-09-24 | [
[
"Leon",
"Genly",
"",
"Catolica del Norte U."
],
[
"Paliathanasis",
"Andronikos",
"",
"Guanajuato U."
],
[
"Morales-Martínez",
"Jorge Luis",
"",
"Guanajuato U."
]
] | We study the phase space of the quintom cosmologies for a class of exponential potentials. We combine normal forms expansions and the center manifold theory in order to describe the dynamics near equilibrium sets. Furthermore, we construct the unstable and center manifold of the massless scalar field cosmology motivated by the numerical results given in Lazkoz and Leon (Phys Lett B 638:303. arXiv:astro-ph/0602590, 2006). We study the role of the curvature on the dynamics. Several monotonic functions are defined on relevant invariant sets for the quintom cosmology. Finally, conservation laws of the cosmological field equations and algebraic solutions are determined by using the symmetry analysis and the singularity analysis. |
1208.3601 | Maur\'icio Richartz | Maur\'icio Richartz, Angus Prain, Silke Weinfurtner, Stefano Liberati | Superradiant scattering of dispersive fields | 31 pages, 11 figures; published in CQG | Class. Quantum Grav. 30, 085009 (2013) | 10.1088/0264-9381/30/8/085009 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by analogue models of classical and quantum field theory in curved
spacetimes and their recent experimental realizations, we consider wave
scattering processes of dispersive fields exhibiting two extra degrees of
freedom. In particular, we investigate how standard superradiant scattering
processes are affected by subluminal or superluminal modifications of the
dispersion relation. We analyze simple 1-dimensional toy-models based on
fourth-order corrections to the standard second order wave equation and show
that low-frequency waves impinging on generic scattering potentials can be
amplified during the process. In specific cases, by assuming a simple step
potential, we determine quantitatively the deviations in the amplification
spectrum that arise due to dispersion, and demonstrate that the amplification
can be further enhanced due to the presence of extra degrees of freedom. We
also consider dispersive scattering processes in which the medium where the
scattering takes place is moving with respect to the observer and show that
superradiance can also be manifest in such situations.
| [
{
"created": "Fri, 17 Aug 2012 14:00:27 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Sep 2012 05:49:33 GMT",
"version": "v2"
},
{
"created": "Mon, 25 Mar 2013 23:36:56 GMT",
"version": "v3"
}
] | 2013-06-14 | [
[
"Richartz",
"Maurício",
""
],
[
"Prain",
"Angus",
""
],
[
"Weinfurtner",
"Silke",
""
],
[
"Liberati",
"Stefano",
""
]
] | Motivated by analogue models of classical and quantum field theory in curved spacetimes and their recent experimental realizations, we consider wave scattering processes of dispersive fields exhibiting two extra degrees of freedom. In particular, we investigate how standard superradiant scattering processes are affected by subluminal or superluminal modifications of the dispersion relation. We analyze simple 1-dimensional toy-models based on fourth-order corrections to the standard second order wave equation and show that low-frequency waves impinging on generic scattering potentials can be amplified during the process. In specific cases, by assuming a simple step potential, we determine quantitatively the deviations in the amplification spectrum that arise due to dispersion, and demonstrate that the amplification can be further enhanced due to the presence of extra degrees of freedom. We also consider dispersive scattering processes in which the medium where the scattering takes place is moving with respect to the observer and show that superradiance can also be manifest in such situations. |
1011.1637 | Luca Fabbri | Luca Fabbri | The most general cosmological dynamics for ELKO Matter Fields | 9 pages | Phys.Lett.B 704: 255-259, 2011 | 10.1016/j.physletb.2011.09.024 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Not long ago, the definition of eigenspinors of charge-conjugation belonging
to a special Wigner class has lead to the unexpected theoretical discovery of a
form of matter with spin 1/2 and mass dimension 1, called ELKO matter field;
ELKO matter fields defined in flat spacetimes have been later extended to
curved and twisted spacetimes, in order to include in their dynamics the
coupling to gravitational fields possessing both metric and torsional degrees
of freedom: the inclusion of non-commuting spinorial covariant derivatives
allows for the introduction of more general dynamical terms influencing the
behaviour of ELKO matter fields. In this paper, we shall solve the theoretical
problem of finding the most general dynamics for ELKO matter, and we will face
the phenomenological issue concerning how the new dynamical terms may affect
the behaviour of ELKO matter; we will see that new effects will arise for which
the very existence of ELKO matter will be endangered, due to the fact that
ELKOs will turn incompatible with the cosmological principle. Thus we have that
anisotropic universes must be taken into account if ELKOs are to be considered
in their most general form.
| [
{
"created": "Sun, 7 Nov 2010 13:41:56 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Sep 2011 10:59:44 GMT",
"version": "v2"
}
] | 2011-10-04 | [
[
"Fabbri",
"Luca",
""
]
] | Not long ago, the definition of eigenspinors of charge-conjugation belonging to a special Wigner class has lead to the unexpected theoretical discovery of a form of matter with spin 1/2 and mass dimension 1, called ELKO matter field; ELKO matter fields defined in flat spacetimes have been later extended to curved and twisted spacetimes, in order to include in their dynamics the coupling to gravitational fields possessing both metric and torsional degrees of freedom: the inclusion of non-commuting spinorial covariant derivatives allows for the introduction of more general dynamical terms influencing the behaviour of ELKO matter fields. In this paper, we shall solve the theoretical problem of finding the most general dynamics for ELKO matter, and we will face the phenomenological issue concerning how the new dynamical terms may affect the behaviour of ELKO matter; we will see that new effects will arise for which the very existence of ELKO matter will be endangered, due to the fact that ELKOs will turn incompatible with the cosmological principle. Thus we have that anisotropic universes must be taken into account if ELKOs are to be considered in their most general form. |
1802.03370 | Peter Horvathy | M. Cariglia, A. Galajinsky, G.W. Gibbons, P.A. Horvathy | Cosmological aspects of the Eisenhart-Duval lift | Minor corrections and precisions, a couple of references added. 34
pages, 3 figures. To be published in European Physical Journal C | null | 10.1140/epjc/s10052-018-5789-x | null | gr-qc astro-ph.CO hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A cosmological extension of the Eisenhart-Duval metric is constructed by
incorporating a cosmic scale factor and the energy-momentum tensor into the
scheme. The dynamics of the spacetime is governed the Ermakov-Milne-Pinney
equation. Killing isometries include spatial translations and rotations,
Newton--Hooke boosts and translation in the null direction. Geodesic motion in
Ermakov-Milne-Pinney cosmoi is analyzed. The derivation of the Ermakov-Lewis
invariant, the Friedmann equations and the Dmitriev-Zel'dovich equations within
the Eisenhart--Duval framework is presented.
| [
{
"created": "Fri, 9 Feb 2018 18:12:28 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Feb 2018 10:30:59 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Apr 2018 10:00:13 GMT",
"version": "v3"
}
] | 2018-05-09 | [
[
"Cariglia",
"M.",
""
],
[
"Galajinsky",
"A.",
""
],
[
"Gibbons",
"G. W.",
""
],
[
"Horvathy",
"P. A.",
""
]
] | A cosmological extension of the Eisenhart-Duval metric is constructed by incorporating a cosmic scale factor and the energy-momentum tensor into the scheme. The dynamics of the spacetime is governed the Ermakov-Milne-Pinney equation. Killing isometries include spatial translations and rotations, Newton--Hooke boosts and translation in the null direction. Geodesic motion in Ermakov-Milne-Pinney cosmoi is analyzed. The derivation of the Ermakov-Lewis invariant, the Friedmann equations and the Dmitriev-Zel'dovich equations within the Eisenhart--Duval framework is presented. |
2003.04242 | Francesco Belgiorno | F. Belgiorno, S.L. Cacciatori, A. Farahat, and A. Vigan\`o | Analogue Hawking Effect: BEC and Surface Waves | 17 pages, 1 figure. Published version. Title a bit changed in PRD | Phys. Rev. D 102, 105004 (2020) | 10.1103/PhysRevD.102.105004 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We take into account two further physical models which play an utmost
importance in the framework of Analogue Gravity. We first consider
Bose--Einstein condensates (BEC) and then surface gravity waves in water. Our
approach is based on the use of the master equation we introduced in a previous
work. A more complete analysis of the singular perturbation problem involved,
with particular reference to the behavior in the neighbourhood of the (real)
turning point and its connection with the WKB approximation, allows us to
verify the thermal character of the particle production process. Furthermore,
we can provide a simple scheme apt to calculate explicitly the greybody factors
in the case of BEC and surface waves. This corroborates the improved approach
we proposed for studying the analogue Hawking effect in the usual limit of
small dispersive effects.
| [
{
"created": "Mon, 9 Mar 2020 16:27:48 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Nov 2020 11:56:33 GMT",
"version": "v2"
}
] | 2020-11-25 | [
[
"Belgiorno",
"F.",
""
],
[
"Cacciatori",
"S. L.",
""
],
[
"Farahat",
"A.",
""
],
[
"Viganò",
"A.",
""
]
] | We take into account two further physical models which play an utmost importance in the framework of Analogue Gravity. We first consider Bose--Einstein condensates (BEC) and then surface gravity waves in water. Our approach is based on the use of the master equation we introduced in a previous work. A more complete analysis of the singular perturbation problem involved, with particular reference to the behavior in the neighbourhood of the (real) turning point and its connection with the WKB approximation, allows us to verify the thermal character of the particle production process. Furthermore, we can provide a simple scheme apt to calculate explicitly the greybody factors in the case of BEC and surface waves. This corroborates the improved approach we proposed for studying the analogue Hawking effect in the usual limit of small dispersive effects. |
1804.09814 | Monica Forte | M\'onica Forte | The extended holographic Dark Energy cosmological models | 7 pages, no figures | null | null | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a general analytical treatment of cosmological models commanded by
three interactive fluids with arbitrary barotropic indexes. The variable
equations of state case are applicable to universes with quintessences, k
essences and holographic fluids and we pay some attention to the holographic
case. We also propose the need to extend the functional forms of the
holographic energy densities that are usual in the literature in the face of
the incompatibility presented by them when special interactions are used.
| [
{
"created": "Wed, 25 Apr 2018 21:57:00 GMT",
"version": "v1"
}
] | 2018-04-27 | [
[
"Forte",
"Mónica",
""
]
] | We present a general analytical treatment of cosmological models commanded by three interactive fluids with arbitrary barotropic indexes. The variable equations of state case are applicable to universes with quintessences, k essences and holographic fluids and we pay some attention to the holographic case. We also propose the need to extend the functional forms of the holographic energy densities that are usual in the literature in the face of the incompatibility presented by them when special interactions are used. |
1111.6526 | Jos\'e Cleriston Campos de Souza | A. B. Pavan, Elisa G. M. Ferreira, Sandro M. R. Micheletti, J. C. C.
de Souza and E. Abdalla | Exact cosmological solutions of models with an interacting dark sector | 14 pages, 4 figures;v.4: published version | Phys. Rev. D 86, 103521 (2012) | 10.1103/PhysRevD.86.103521 | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we extend the first order formalism for cosmological models that
present an interaction between a fermionic and a scalar field. Cosmological
exact solutions describing universes filled with interacting dark energy and
dark matter have been obtained. Viable cosmological solutions with an early
period of decelerated expansion followed by late acceleration have been found,
notably one which presents a dark matter component dominating in the past and a
dark energy component dominating in the future. In another one, the dark energy
alone is the responsible for both periods, similar to a Chaplygin gas case.
Exclusively accelerating solutions have also been obtained.
| [
{
"created": "Mon, 28 Nov 2011 17:27:13 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Sep 2012 18:27:42 GMT",
"version": "v2"
},
{
"created": "Tue, 23 Oct 2012 20:40:02 GMT",
"version": "v3"
},
{
"created": "Wed, 21 Nov 2012 18:14:55 GMT",
"version": "v4"
}
] | 2012-11-22 | [
[
"Pavan",
"A. B.",
""
],
[
"Ferreira",
"Elisa G. M.",
""
],
[
"Micheletti",
"Sandro M. R.",
""
],
[
"de Souza",
"J. C. C.",
""
],
[
"Abdalla",
"E.",
""
]
] | In this work we extend the first order formalism for cosmological models that present an interaction between a fermionic and a scalar field. Cosmological exact solutions describing universes filled with interacting dark energy and dark matter have been obtained. Viable cosmological solutions with an early period of decelerated expansion followed by late acceleration have been found, notably one which presents a dark matter component dominating in the past and a dark energy component dominating in the future. In another one, the dark energy alone is the responsible for both periods, similar to a Chaplygin gas case. Exclusively accelerating solutions have also been obtained. |
1601.02174 | Norichika Sago | Norichika Sago, Ryuichi Fujita, Hiroyuki Nakano | Accuracy of the Post-Newtonian Approximation for Extreme-Mass Ratio
Inspirals from Black-hole Perturbation Approach | 8 pages, 6 figures, minor modifications to match the published
version in PRD | Phys. Rev. D 93, 104023 (2016) | 10.1103/PhysRevD.93.104023 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the accuracy of the post-Newtonian (PN) approximation and its
region of validity for quasi-circular orbits of a point particle in the Kerr
spacetime, by using an analytically known highest post-Newtonian order
gravitational energy flux and accurate numerical results in the black hole
perturbation approach. It is found that regions of validity become larger for
higher PN order results although there are several local maximums in regions of
validity for relatively low-PN order results. This might imply that higher PN
order calculations are also encouraged for comparable-mass binaries.
| [
{
"created": "Sun, 10 Jan 2016 03:06:41 GMT",
"version": "v1"
},
{
"created": "Wed, 25 May 2016 22:54:50 GMT",
"version": "v2"
}
] | 2016-05-27 | [
[
"Sago",
"Norichika",
""
],
[
"Fujita",
"Ryuichi",
""
],
[
"Nakano",
"Hiroyuki",
""
]
] | We revisit the accuracy of the post-Newtonian (PN) approximation and its region of validity for quasi-circular orbits of a point particle in the Kerr spacetime, by using an analytically known highest post-Newtonian order gravitational energy flux and accurate numerical results in the black hole perturbation approach. It is found that regions of validity become larger for higher PN order results although there are several local maximums in regions of validity for relatively low-PN order results. This might imply that higher PN order calculations are also encouraged for comparable-mass binaries. |
1603.04075 | Enrico Barausse | Enrico Barausse, Nicolas Yunes and Katie Chamberlain | Theory-Agnostic Constraints on Black-Hole Dipole Radiation with
Multi-Band Gravitational-Wave Astrophysics | 6 pages, 1 figure; slight changes to text and figure (which now uses
design aLIGO instead of current aLIGO for the combined eLISA-aLIGO
costraints), conclusions unchanged. Matches version accepted by PRL | Phys. Rev. Lett. 116, 241104 (2016) | 10.1103/PhysRevLett.116.241104 | null | gr-qc astro-ph.CO astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The aLIGO detection of the black-hole binary GW150914 opened a new era for
probing extreme gravity. Many gravity theories predict the emission of dipole
gravitational radiation by binaries. This is excluded to high accuracy in
binary pulsars, but entire classes of theories predict this effect
predominantly (or only) in binaries involving black holes. Joint observations
of GW150914-like systems by aLIGO and eLISA will improve bounds on dipole
emission from black-hole binaries by six orders of magnitude relative to
current constraints, provided that eLISA is not dramatically descoped.
| [
{
"created": "Sun, 13 Mar 2016 21:09:45 GMT",
"version": "v1"
},
{
"created": "Wed, 11 May 2016 09:10:47 GMT",
"version": "v2"
}
] | 2016-06-22 | [
[
"Barausse",
"Enrico",
""
],
[
"Yunes",
"Nicolas",
""
],
[
"Chamberlain",
"Katie",
""
]
] | The aLIGO detection of the black-hole binary GW150914 opened a new era for probing extreme gravity. Many gravity theories predict the emission of dipole gravitational radiation by binaries. This is excluded to high accuracy in binary pulsars, but entire classes of theories predict this effect predominantly (or only) in binaries involving black holes. Joint observations of GW150914-like systems by aLIGO and eLISA will improve bounds on dipole emission from black-hole binaries by six orders of magnitude relative to current constraints, provided that eLISA is not dramatically descoped. |
0905.3212 | Muhammad Sharif | M. Sharif and Bushra Majeed | Teleparallel Killing Vectors of Spherically Symmetric Spacetimes | 14 pages, accepted for publication in Communications in Theoretical
Physics | Commun. Theor. Phys. 52(2009)435-440 | 10.1088/0253-6102/52/3/11 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, Killing vectors of spherically spacetimes have been evaluated
in the context of teleparallel theory of gravitation. Further, we investigate
the Killing vectors of the Friedmann metrics. It is found that for static
spherically spacetimes the number of Killing vectors turn out to be
\emph{seven} while for the Friedmann models, we obtain \emph{six} teleparallel
Killing vectors. The results are then compared with those of General
Relativity. We conclude that both of these descriptions of gravity do not
provide the consistent results in general. However, these results may coincide
under certain conditions for a particular spacetime.
| [
{
"created": "Wed, 20 May 2009 02:21:04 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Sharif",
"M.",
""
],
[
"Majeed",
"Bushra",
""
]
] | In this paper, Killing vectors of spherically spacetimes have been evaluated in the context of teleparallel theory of gravitation. Further, we investigate the Killing vectors of the Friedmann metrics. It is found that for static spherically spacetimes the number of Killing vectors turn out to be \emph{seven} while for the Friedmann models, we obtain \emph{six} teleparallel Killing vectors. The results are then compared with those of General Relativity. We conclude that both of these descriptions of gravity do not provide the consistent results in general. However, these results may coincide under certain conditions for a particular spacetime. |
gr-qc/0311066 | Daniele Oriti | Daniele Oriti | Spin Foam Models of Quantum Spacetime | 337 pages, 31 figures; Ph.D. Thesis, University of Cambridge | null | null | null | gr-qc | null | Spin foam models are a new approach to a formulation of quantum gravity which
is fully background independent, non-perturbative, and covariant, in the spirit
of path integral formulations of quantum field theory. In this thesis we
describe in details the general ideas and formalism of spin foam models, and
review many of the results obtained recently in this approach. We concentrate,
for the case of 3-dimensional quantum gravity, on the Turaev-Viro model, and,
in the 4-dimensional case, which is our main concern, on the Barrett-Crane
model. In particular, for the Barrett-Crane model: we describe the general
ideas behind its construction, and review what has been achieved up to date,
discuss in details its links with the classical formulations of gravity as
constrained topological field theory; we show a derivation of the model from a
lattice gauge theory perspective, in the general case of manifold with
boundaries, presenting also a few possible variations of the procedure used,
discussing the problems they present; we analyse in details the classical and
quantum geometry; we also describe how, from the same perspective, a spin foam
model that couples quantum gravity to any gauge theory may be constructed;
finally, we describe a general scheme for causal spin foam models, how the
Barrett-Crane model can be modified to implement causality and to fit in such a
scheme, and the resulting link with the quantum causal set approach to quantum
gravity.
| [
{
"created": "Thu, 20 Nov 2003 15:16:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Oriti",
"Daniele",
""
]
] | Spin foam models are a new approach to a formulation of quantum gravity which is fully background independent, non-perturbative, and covariant, in the spirit of path integral formulations of quantum field theory. In this thesis we describe in details the general ideas and formalism of spin foam models, and review many of the results obtained recently in this approach. We concentrate, for the case of 3-dimensional quantum gravity, on the Turaev-Viro model, and, in the 4-dimensional case, which is our main concern, on the Barrett-Crane model. In particular, for the Barrett-Crane model: we describe the general ideas behind its construction, and review what has been achieved up to date, discuss in details its links with the classical formulations of gravity as constrained topological field theory; we show a derivation of the model from a lattice gauge theory perspective, in the general case of manifold with boundaries, presenting also a few possible variations of the procedure used, discussing the problems they present; we analyse in details the classical and quantum geometry; we also describe how, from the same perspective, a spin foam model that couples quantum gravity to any gauge theory may be constructed; finally, we describe a general scheme for causal spin foam models, how the Barrett-Crane model can be modified to implement causality and to fit in such a scheme, and the resulting link with the quantum causal set approach to quantum gravity. |
1312.5553 | Felipe Faria | F. F. Faria | Massive conformal gravity | v2: 6 pages, some missing terms were added in the field equation (7).
v3: 9 pages, several improvements to match the published version | Advances in High Energy Physics, vol. 2014, Article ID 520259, 4
pages, 2014 | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article we construct a massive theory of gravity that is invariant
under conformal transformations. The massive action of the theory depend on the
metric tensor and a scalar field, which are considered as the only field
variables. We find the vacuum field equations of the theory and the solution of
its Newtonian limit.
| [
{
"created": "Thu, 19 Dec 2013 14:05:22 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Jan 2014 20:00:10 GMT",
"version": "v2"
},
{
"created": "Mon, 15 Dec 2014 10:34:41 GMT",
"version": "v3"
}
] | 2014-12-16 | [
[
"Faria",
"F. F.",
""
]
] | In this article we construct a massive theory of gravity that is invariant under conformal transformations. The massive action of the theory depend on the metric tensor and a scalar field, which are considered as the only field variables. We find the vacuum field equations of the theory and the solution of its Newtonian limit. |
2305.00686 | Thanasis Karakasis | Thanasis Karakasis, George Koutsoumbas, Eleftherios Papantonopoulos | Black Holes with Scalar Hair in Three Dimensions | Accepted for publication in PRD | null | 10.1103/PhysRevD.107.124047 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | Three - dimensional static and spinning black hole solutions of the
Einstein-Klein-Gordon system are obtained for a particular scalar field
configuration. At large distances, and for small scalar field, the solutions
reduce to the BTZ black hole. The scalar field dresses the black hole with
secondary scalar hair, since the scalar charge is related to the conserved
black hole mass and is not an independent charge. A self interacting potential
is included, containing a mass term that is above the Breitenlohner-Freedman
bound in three dimensions. Independence of the scalar potential from the
conserved black hole charges, imposes fixed mass and angular momentum to scalar
charge ratios. The thermodynamic properties as well as the energy conditions of
the black hole are analysed.
| [
{
"created": "Mon, 1 May 2023 06:57:58 GMT",
"version": "v1"
},
{
"created": "Tue, 2 May 2023 09:52:32 GMT",
"version": "v2"
},
{
"created": "Mon, 12 Jun 2023 20:06:38 GMT",
"version": "v3"
}
] | 2023-07-11 | [
[
"Karakasis",
"Thanasis",
""
],
[
"Koutsoumbas",
"George",
""
],
[
"Papantonopoulos",
"Eleftherios",
""
]
] | Three - dimensional static and spinning black hole solutions of the Einstein-Klein-Gordon system are obtained for a particular scalar field configuration. At large distances, and for small scalar field, the solutions reduce to the BTZ black hole. The scalar field dresses the black hole with secondary scalar hair, since the scalar charge is related to the conserved black hole mass and is not an independent charge. A self interacting potential is included, containing a mass term that is above the Breitenlohner-Freedman bound in three dimensions. Independence of the scalar potential from the conserved black hole charges, imposes fixed mass and angular momentum to scalar charge ratios. The thermodynamic properties as well as the energy conditions of the black hole are analysed. |
1712.06412 | Ramil Izmailov | R.Kh. Karimov, R.N. Izmailov, G.M. Garipova and K.K. Nandi | Sagnac delay in the Kerr-dS space-time: Implications for Mach's
principle | 15 pages. arXiv admin note: text overlap with arXiv:1709.08413 | Eur. Phys. J. Plus (2018) 133: 44 | 10.1140/epjp/i2018-11919-x | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Relativistic twin paradox can have important implications for Mach's
principle. It has been recently argued that the behavior of the time asynchrony
(different aging of twins) between two flying clocks along closed loops can be
attributed to the existence of an absolute spacetime, which makes Mach's
principle unfeasible. In this paper, we shall revisit, and support, this
argument from a different viewpoint using the Sagnac delay. This is possible
since the above time asynchrony is known to be exactly the same as the Sagnac
delay between two circumnavigating light rays re-uniting at the orbiting
source/receiver. We shall calculate the effect of mass $M$ and cosmological
constant $\Lambda$ on the delay in the general case of Kerr-de Sitter
spacetime. It follows that, in the independent limits $M\rightarrow 0$, spin
$a\rightarrow 0$ and $\Lambda\rightarrow 0$, while the Kerr-dS metric reduces
to Minkowski metric, the clocks need not tick in consonance since there will
still appear a non-zero observable Sagnac delay. While we do not measure
spacetime itself, we do measure the Sagnac effect, which signifies an absolute
substantive Minkowski spacetime instead of a void. We shall demonstrate a
completely different limiting behavior of Sagnac delay, heretofore unknown,
between the case of non-geodesic and geodesic source/observer motion.
| [
{
"created": "Mon, 18 Dec 2017 14:21:05 GMT",
"version": "v1"
}
] | 2018-04-03 | [
[
"Karimov",
"R. Kh.",
""
],
[
"Izmailov",
"R. N.",
""
],
[
"Garipova",
"G. M.",
""
],
[
"Nandi",
"K. K.",
""
]
] | Relativistic twin paradox can have important implications for Mach's principle. It has been recently argued that the behavior of the time asynchrony (different aging of twins) between two flying clocks along closed loops can be attributed to the existence of an absolute spacetime, which makes Mach's principle unfeasible. In this paper, we shall revisit, and support, this argument from a different viewpoint using the Sagnac delay. This is possible since the above time asynchrony is known to be exactly the same as the Sagnac delay between two circumnavigating light rays re-uniting at the orbiting source/receiver. We shall calculate the effect of mass $M$ and cosmological constant $\Lambda$ on the delay in the general case of Kerr-de Sitter spacetime. It follows that, in the independent limits $M\rightarrow 0$, spin $a\rightarrow 0$ and $\Lambda\rightarrow 0$, while the Kerr-dS metric reduces to Minkowski metric, the clocks need not tick in consonance since there will still appear a non-zero observable Sagnac delay. While we do not measure spacetime itself, we do measure the Sagnac effect, which signifies an absolute substantive Minkowski spacetime instead of a void. We shall demonstrate a completely different limiting behavior of Sagnac delay, heretofore unknown, between the case of non-geodesic and geodesic source/observer motion. |
1205.0469 | Nangue Alexis Alex | Norbert Noutchegueme and Alexis Nangue | Einstein-Maxwell-Massive Scalar Field System in 3+1 formulation on
Bianchi Spacetimes type I-VIII | 45 pages | null | null | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Global existence to the coupled Einstein-Maxwell-Massive Scalar Field system
which rules the dynamics of a kind of charged pure matter in the presence of a
massive scalar field is proved, in Bianchi I-VIII spacetimes; asymptotic
behaviour, geodesic completeness, energy conditions are investigated in the
case of a cosmological constant bounded from below by a strictly negative
constant depending only on the massive scalar field.
| [
{
"created": "Wed, 2 May 2012 15:44:21 GMT",
"version": "v1"
}
] | 2012-05-03 | [
[
"Noutchegueme",
"Norbert",
""
],
[
"Nangue",
"Alexis",
""
]
] | Global existence to the coupled Einstein-Maxwell-Massive Scalar Field system which rules the dynamics of a kind of charged pure matter in the presence of a massive scalar field is proved, in Bianchi I-VIII spacetimes; asymptotic behaviour, geodesic completeness, energy conditions are investigated in the case of a cosmological constant bounded from below by a strictly negative constant depending only on the massive scalar field. |
1503.03439 | Saibal Ray | Piyali Bhar, Farook Rahaman, Saibal Ray and Vikram Chatterjee | Possibility of higher dimensional anisotropic compact star | 21 pages, 6 figures, 1 table, Substantial modification in the whole
manuscript, Accepted in Eur. Phys. J. C | null | 10.1140/epjc/s10052-015-3375-z | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have provided here a new class of interior solutions for anisotropic stars
admitting conformal motion in higher dimensional noncommutative spacetime. The
Einstein fields equations are solved by choosing a particular density
distribution function of Lorentzian type \cite{Nozari} under noncommutative
geometry. Several cases with dimensions $4D$ and higher, e.g. $5D$, $6D$ and
$11D$ have been discussed separately. An overall observation is that the model
parameters, such as density, radial pressure, transverse pressure, anisotropy
all are well behaved and represent a compact star with radius $4.17$ km.
However, emphasis has been given on the acceptability of the model from
physical point of view. As a consequence it is observed that higher dimensions,
i.e. beyond $4D$ spacetime, exhibit several interesting yet bizarre features
which are not at all untenable for a compact stellar model of strange quark
type and thus dictates a possibility of its extra dimensional existence.
| [
{
"created": "Wed, 29 Oct 2014 11:21:09 GMT",
"version": "v1"
},
{
"created": "Thu, 14 May 2015 06:50:45 GMT",
"version": "v2"
}
] | 2015-05-15 | [
[
"Bhar",
"Piyali",
""
],
[
"Rahaman",
"Farook",
""
],
[
"Ray",
"Saibal",
""
],
[
"Chatterjee",
"Vikram",
""
]
] | We have provided here a new class of interior solutions for anisotropic stars admitting conformal motion in higher dimensional noncommutative spacetime. The Einstein fields equations are solved by choosing a particular density distribution function of Lorentzian type \cite{Nozari} under noncommutative geometry. Several cases with dimensions $4D$ and higher, e.g. $5D$, $6D$ and $11D$ have been discussed separately. An overall observation is that the model parameters, such as density, radial pressure, transverse pressure, anisotropy all are well behaved and represent a compact star with radius $4.17$ km. However, emphasis has been given on the acceptability of the model from physical point of view. As a consequence it is observed that higher dimensions, i.e. beyond $4D$ spacetime, exhibit several interesting yet bizarre features which are not at all untenable for a compact stellar model of strange quark type and thus dictates a possibility of its extra dimensional existence. |
2201.00652 | Erik Lentz | Erik W. Lentz | Hyper-Fast Positive Energy Warp Drives | 8 pages, 1 figure; Contribution to the Sixteenth Marcel Grossman
Conference (MG16, Rome, Italy, July 2021) | null | null | null | gr-qc astro-ph.HE hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Solitons in space-time capable of transporting time-like observers at
superluminal speeds have long been tied to violations of the weak, strong, and
dominant energy conditions of general relativity. This trend was recently
broken by a new approach that identified soliton solutions capable of
superluminal travel while being sourced by purely positive energy densities.
This is the first example of hyper-fast solitons satisfying the weak energy
condition, reopening the discussion of superluminal mechanisms rooted in
conventional physics. This article summarizes the recent finding and its
context in the literature. Remaining challenges to autonomous superluminal
travel, such as the dominant energy condition, horizons, and the identification
of a creation mechanism are also discussed.
| [
{
"created": "Thu, 30 Dec 2021 18:50:01 GMT",
"version": "v1"
}
] | 2022-01-04 | [
[
"Lentz",
"Erik W.",
""
]
] | Solitons in space-time capable of transporting time-like observers at superluminal speeds have long been tied to violations of the weak, strong, and dominant energy conditions of general relativity. This trend was recently broken by a new approach that identified soliton solutions capable of superluminal travel while being sourced by purely positive energy densities. This is the first example of hyper-fast solitons satisfying the weak energy condition, reopening the discussion of superluminal mechanisms rooted in conventional physics. This article summarizes the recent finding and its context in the literature. Remaining challenges to autonomous superluminal travel, such as the dominant energy condition, horizons, and the identification of a creation mechanism are also discussed. |
gr-qc/0612153 | Alberto Lobo | Alberto Lobo, Miquel Nofrarias, Juan Ramos-Castro, Josep Sanjuan,
Aleix Conchillo, Jose Antonio Ortega, Xevi Xirgu, Henrique Araujo, Cesar
Boatella, Mokhtar Chmeissani, Catia Grimani, Carles Puigdengoles, Peter Wass,
Enrique Garcia-Berro, Sergi Garcia, Lluis Martinez and Gustau Montero | In-flight Diagnostics in LISA Pathfinder | 7 pages, 1 figure, presented at the 6th LISA Symposium, Goddard Space
Flight Center, June 2006 | AIPConf.Proc.873:522-528,2006 | 10.1063/1.2405094 | null | gr-qc | null | LISA PathFinder (LPF) will be flown with the objective to test in space key
technologies for LISA. However its sensitivity goals are, for good reason, one
order of magnitude less than those which LISA will have to meet, both in
drag-free and optical metrology requirements, and in the observation frequency
band. While the expected success of LPF will of course be of itself a major
step forward to LISA, one might not forget that a further improvement by an
order of magnitude in performance will still be needed. Clues for the last leap
are to be derived from proper disentanglement of the various sources of noise
which contribute to the total noise, as measured in flight during the
PathFinder mission. This paper describes the principles, workings and
requirements of one of the key tools to serve the above objective: the
diagnostics subsystem. This consists in sets of temperature, magnetic field,
and particle counter sensors, together with generators of controlled thermal
and magnetic perturbations. At least during the commissioning phase, the latter
will be used to identify feed-through coefficients between diagnostics sensor
readings and associated actual noise contributions. A brief progress report of
the current state of development of the diagnostics subsystem will be given as
well.
| [
{
"created": "Sat, 23 Dec 2006 10:58:51 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Lobo",
"Alberto",
""
],
[
"Nofrarias",
"Miquel",
""
],
[
"Ramos-Castro",
"Juan",
""
],
[
"Sanjuan",
"Josep",
""
],
[
"Conchillo",
"Aleix",
""
],
[
"Ortega",
"Jose Antonio",
""
],
[
"Xirgu",
"Xevi",
""
],
[
"Araujo",
"Henrique",
""
],
[
"Boatella",
"Cesar",
""
],
[
"Chmeissani",
"Mokhtar",
""
],
[
"Grimani",
"Catia",
""
],
[
"Puigdengoles",
"Carles",
""
],
[
"Wass",
"Peter",
""
],
[
"Garcia-Berro",
"Enrique",
""
],
[
"Garcia",
"Sergi",
""
],
[
"Martinez",
"Lluis",
""
],
[
"Montero",
"Gustau",
""
]
] | LISA PathFinder (LPF) will be flown with the objective to test in space key technologies for LISA. However its sensitivity goals are, for good reason, one order of magnitude less than those which LISA will have to meet, both in drag-free and optical metrology requirements, and in the observation frequency band. While the expected success of LPF will of course be of itself a major step forward to LISA, one might not forget that a further improvement by an order of magnitude in performance will still be needed. Clues for the last leap are to be derived from proper disentanglement of the various sources of noise which contribute to the total noise, as measured in flight during the PathFinder mission. This paper describes the principles, workings and requirements of one of the key tools to serve the above objective: the diagnostics subsystem. This consists in sets of temperature, magnetic field, and particle counter sensors, together with generators of controlled thermal and magnetic perturbations. At least during the commissioning phase, the latter will be used to identify feed-through coefficients between diagnostics sensor readings and associated actual noise contributions. A brief progress report of the current state of development of the diagnostics subsystem will be given as well. |
1210.1787 | Steffen Gielen | Steffen Gielen | Spontaneous breaking of Lorentz symmetry for canonical gravity | 8 pages, contribution to the proceedings of the conference
"Relativity and Gravitation - 100 years after Einstein in Prague"; v2: added
heading "References" | Springer Proceedings in Physics 57 (2014) 497-503 | 10.1007/978-3-319-06761-2_70 | pi-qg-300 | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the Ashtekar-Barbero formulation of canonical general relativity based on
an SU(2) connection, Lorentz covariance is a subtle issue which has been the
focus of some debate. Here we present a Lorentz covariant formulation
generalising the notion of a foliation of spacetime to a field of local
observers which specify a time direction only locally. This field spontaneously
breaks the local SO(3,1) symmetry down to a subgroup SO(3); we show that the
apparent symmetry breaking to SO(3) is not in conflict with Lorentz covariance.
We give a geometric picture of our construction as Cartan geometrodynamics and
outline further applications of the formalism of local observers, motivating
the idea that observer space, instead of spacetime, should serve as the
fundamental arena for gravitational physics.
| [
{
"created": "Fri, 5 Oct 2012 15:31:25 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Oct 2012 02:35:15 GMT",
"version": "v2"
}
] | 2014-06-18 | [
[
"Gielen",
"Steffen",
""
]
] | In the Ashtekar-Barbero formulation of canonical general relativity based on an SU(2) connection, Lorentz covariance is a subtle issue which has been the focus of some debate. Here we present a Lorentz covariant formulation generalising the notion of a foliation of spacetime to a field of local observers which specify a time direction only locally. This field spontaneously breaks the local SO(3,1) symmetry down to a subgroup SO(3); we show that the apparent symmetry breaking to SO(3) is not in conflict with Lorentz covariance. We give a geometric picture of our construction as Cartan geometrodynamics and outline further applications of the formalism of local observers, motivating the idea that observer space, instead of spacetime, should serve as the fundamental arena for gravitational physics. |
2003.11587 | Graeme Milton | Graeme W. Milton | A possible explanation of dark matter and dark energy involving a vector
torsion field | 20 pages, 4 figures | null | null | null | gr-qc | http://creativecommons.org/licenses/by-nc-nd/4.0/ | A simple gravitational model with torsion is studied, and it is suggested
that it could explain the dark matter and dark energy in the universe. It can
be reinterpreted as a model using the Einstein gravitational equations where
spacetime has regions filled with a perfect fluid with negative energy
(pressure) and positive mass density, other regions containing an anisotropic
substance that in the rest frame (where the momentum is zero) has negative mass
density and a uniaxial stress tensor, and possibly other "luminal" regions
where there is no rest frame. The torsion vector field is inhomogeneous
throughout spacetime, and possibly turbulent. Numerical simulations should
reveal whether or not the equations are consistent with cosmological
observations of dark matter and dark energy.
| [
{
"created": "Wed, 25 Mar 2020 19:09:42 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Mar 2020 17:56:53 GMT",
"version": "v2"
},
{
"created": "Fri, 17 Apr 2020 18:53:14 GMT",
"version": "v3"
},
{
"created": "Sun, 21 Mar 2021 20:28:48 GMT",
"version": "v4"
},
{
"created": "Fri, 25 Mar 2022 16:40:58 GMT",
"version": "v5"
}
] | 2022-03-28 | [
[
"Milton",
"Graeme W.",
""
]
] | A simple gravitational model with torsion is studied, and it is suggested that it could explain the dark matter and dark energy in the universe. It can be reinterpreted as a model using the Einstein gravitational equations where spacetime has regions filled with a perfect fluid with negative energy (pressure) and positive mass density, other regions containing an anisotropic substance that in the rest frame (where the momentum is zero) has negative mass density and a uniaxial stress tensor, and possibly other "luminal" regions where there is no rest frame. The torsion vector field is inhomogeneous throughout spacetime, and possibly turbulent. Numerical simulations should reveal whether or not the equations are consistent with cosmological observations of dark matter and dark energy. |
2004.03947 | Sergey L Cherkas | Sergey L. Cherkas and Vladimir L. Kalashnikov | Eicheons instead of Black holes | 18 pages. The term "eicheon" refers to the fundamental work
"Gravitation und Elektrizitat" by Hermann Weyl where the concept of gauge
field theory ("Eichfeldtheorie") was invented for the first time | Phys. Scr. 95 (2020) 085009 | 10.1088/1402-4896/aba3aa | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new spherically-symmetric solution for a gravitational field is found in
the conformally-unimodular metric. It is shown, that the surface of the black
hole horizon in the standard Schwarzschild metric can be squeezed to a point by
converting coordinates to the conformally-unimodular metric. In this new
metric, there is no black hole horizon, while the naked singularity corresponds
to a point massive particle. The reason for the study of this particular gauge
(i.e., conformally-unimodular metric) is its relation to the vacuum energy
problem. That aims to relate it to other physical phenomena (including black
holes), and one could argue that they should be considered in this particular
metric. That means the violation of the gauge invariance of the general theory
of relativity. As a result, the nonsingular "eicheons" appear as the non-point
compact objects with different masses and structures. They are a final product
of the stellar collapse, with the masses exceeding the
Tolman-Oppenheimer-Volkoff limit.
| [
{
"created": "Wed, 8 Apr 2020 11:42:35 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jun 2020 08:16:39 GMT",
"version": "v2"
},
{
"created": "Sat, 11 Jul 2020 10:20:54 GMT",
"version": "v3"
}
] | 2020-08-24 | [
[
"Cherkas",
"Sergey L.",
""
],
[
"Kalashnikov",
"Vladimir L.",
""
]
] | A new spherically-symmetric solution for a gravitational field is found in the conformally-unimodular metric. It is shown, that the surface of the black hole horizon in the standard Schwarzschild metric can be squeezed to a point by converting coordinates to the conformally-unimodular metric. In this new metric, there is no black hole horizon, while the naked singularity corresponds to a point massive particle. The reason for the study of this particular gauge (i.e., conformally-unimodular metric) is its relation to the vacuum energy problem. That aims to relate it to other physical phenomena (including black holes), and one could argue that they should be considered in this particular metric. That means the violation of the gauge invariance of the general theory of relativity. As a result, the nonsingular "eicheons" appear as the non-point compact objects with different masses and structures. They are a final product of the stellar collapse, with the masses exceeding the Tolman-Oppenheimer-Volkoff limit. |
2310.09539 | Gabriele Gionti S.J. | Gabriele Gionti S.J., Matteo Galaverni | On the canonical equivalence between Jordan and Einstein frames | 18 pages, 2 figures, references added; accepted for publication | null | null | null | gr-qc hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A longstanding issue is the classical equivalence between the Jordan and the
Einstein frames, which is considered just a field redefinition of the metric
tensor and the scalar field. In this work, based on the previous result that
the Hamiltonian transformations from the Jordan to the Einstein frame are not
canonical on the extended phase space, we study the possibility of the
existence of canonical transformations. We show that on the reduced phase space
-- defined by suitable gauge fixing of the lapse and shifts functions -- these
transformations are Hamiltonian canonical. Poisson brackets are replaced by
Dirac's brackets following the Bergman-Dirac's procedure. The Hamiltonian
canonical transformations map solutions of the equations of motion in the
Jordan frame into solutions of the equations of motion in the Einstein frame.
| [
{
"created": "Sat, 14 Oct 2023 09:27:51 GMT",
"version": "v1"
},
{
"created": "Sat, 24 Feb 2024 11:04:14 GMT",
"version": "v2"
}
] | 2024-02-27 | [
[
"J.",
"Gabriele Gionti S.",
""
],
[
"Galaverni",
"Matteo",
""
]
] | A longstanding issue is the classical equivalence between the Jordan and the Einstein frames, which is considered just a field redefinition of the metric tensor and the scalar field. In this work, based on the previous result that the Hamiltonian transformations from the Jordan to the Einstein frame are not canonical on the extended phase space, we study the possibility of the existence of canonical transformations. We show that on the reduced phase space -- defined by suitable gauge fixing of the lapse and shifts functions -- these transformations are Hamiltonian canonical. Poisson brackets are replaced by Dirac's brackets following the Bergman-Dirac's procedure. The Hamiltonian canonical transformations map solutions of the equations of motion in the Jordan frame into solutions of the equations of motion in the Einstein frame. |
1308.2385 | Christian Wiesendanger | C. Wiesendanger | General Relativity as the Classical Limit of the Renormalizable Gauge
Theory of Volume Preserving Diffeomorphisms | 16 pages | null | 10.4236/jmp.2014.510098 | null | gr-qc hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The different roles and natures of spacetime appearing in a quantum field
theory and in classical physics are analyzed implying that a quantum theory of
gravitation is not necessarily a quantum theory of curved spacetime. Developing
an alternative approach to quantum gravity starts with the postulate that
inertial and gravitational energy-momentum need not be the same for virtual
quantum states. Separating their roles naturally leads to the quantum gauge
field theory of volume-preserving diffeomorphisms of an inner four-dimensional
space. The classical limit of this theory coupled to a quantized scalar field
is derived for an on-shell particle where inertial and gravitational
energy-momentum coincide. In that process the symmetry under volume-preserving
diffeomorphisms disappears and a new symmetry group emerges: the group of
coordinate transformations of four-dimensional spacetime and with it General
Relativity coupled to a classical relativistic point particle.
| [
{
"created": "Sun, 11 Aug 2013 12:10:16 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Oct 2013 14:14:39 GMT",
"version": "v2"
}
] | 2015-06-16 | [
[
"Wiesendanger",
"C.",
""
]
] | The different roles and natures of spacetime appearing in a quantum field theory and in classical physics are analyzed implying that a quantum theory of gravitation is not necessarily a quantum theory of curved spacetime. Developing an alternative approach to quantum gravity starts with the postulate that inertial and gravitational energy-momentum need not be the same for virtual quantum states. Separating their roles naturally leads to the quantum gauge field theory of volume-preserving diffeomorphisms of an inner four-dimensional space. The classical limit of this theory coupled to a quantized scalar field is derived for an on-shell particle where inertial and gravitational energy-momentum coincide. In that process the symmetry under volume-preserving diffeomorphisms disappears and a new symmetry group emerges: the group of coordinate transformations of four-dimensional spacetime and with it General Relativity coupled to a classical relativistic point particle. |
1908.02595 | Valerio Faraoni | Jeremy C\^ot\'e, Marianne Lapierre-L\'eonard, and Valerio Faraoni | Spacetime mappings of the Brown-York quasilocal energy | 6 pages, to appear in Eur. Phys. J. C | null | 10.1140/epjc/s10052-019-7205-6 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In several areas of theoretical physics it is useful to know how a quasilocal
energy transforms under conformal rescalings or generalized Kerr-Schild
mappings. We derive the transformation properties of the Brown-York quasilocal
energy in spherical symmetry and we contrast them with those of the
Misner-Sharp-Hernandez energy.
| [
{
"created": "Wed, 7 Aug 2019 12:43:11 GMT",
"version": "v1"
}
] | 2019-09-04 | [
[
"Côté",
"Jeremy",
""
],
[
"Lapierre-Léonard",
"Marianne",
""
],
[
"Faraoni",
"Valerio",
""
]
] | In several areas of theoretical physics it is useful to know how a quasilocal energy transforms under conformal rescalings or generalized Kerr-Schild mappings. We derive the transformation properties of the Brown-York quasilocal energy in spherical symmetry and we contrast them with those of the Misner-Sharp-Hernandez energy. |
0907.3163 | Luisa T. Buchman | Luisa T. Buchman, Harald P. Pfeiffer, and James M. Bardeen | Black hole initial data on hyperboloidal slices | version for publication in Phys. Rev. D | Phys.Rev.D80:084024,2009 | 10.1103/PhysRevD.80.084024 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We generalize Bowen-York black hole initial data to hyperboloidal constant
mean curvature slices which extend to future null infinity. We solve this
initial value problem numerically for several cases, including unequal mass
binary black holes with spins and boosts. The singularity at null infinity in
the Hamiltonian constraint associated with a constant mean curvature
hypersurface does not pose any particular difficulties. The inner boundaries of
our slices are minimal surfaces. Trumpet configurations are explored both
analytically and numerically.
| [
{
"created": "Fri, 17 Jul 2009 23:16:04 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Oct 2009 05:39:37 GMT",
"version": "v2"
}
] | 2009-11-05 | [
[
"Buchman",
"Luisa T.",
""
],
[
"Pfeiffer",
"Harald P.",
""
],
[
"Bardeen",
"James M.",
""
]
] | We generalize Bowen-York black hole initial data to hyperboloidal constant mean curvature slices which extend to future null infinity. We solve this initial value problem numerically for several cases, including unequal mass binary black holes with spins and boosts. The singularity at null infinity in the Hamiltonian constraint associated with a constant mean curvature hypersurface does not pose any particular difficulties. The inner boundaries of our slices are minimal surfaces. Trumpet configurations are explored both analytically and numerically. |
1510.05055 | Eric Greenwood | Eric Greenwood | Classical and Quantum Equations of Motion of an n-dimesional BTZ Black
Hole | 10 pages. arXiv admin note: text overlap with arXiv:0912.1860 | null | 10.1016/j.physletb.2016.03.041 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the gravitational collapse of a non-rotating $n$-dimensional
BTZ black hole in AdS space in the context of both classical and quantum
mechanics. This is done by first deriving the conserved mass of a "spherically"
symmetric domain wall, which is taken as the classical Hamiltonian of the black
hole. Upon deriving the conserved mass, we also point out that, for a
"spherically" symmetric shell, there is an easy and straight-forward way of
determining the conserved mass, which is related to the proper time derivative
of the interior and exterior times. This method for determining the conserved
mass is generic to any situation (i.e. any equation of state), since it only
depends on the energy per unit area, $\sigma$, of the shell.
Classically, we show that the time taken for gravitational collapse follows
that of the typical formation of a black hole via gravitational collapse, that
is, an asymptotic observer will see that the collapse takes an infinite amount
of time to occur, while an infalling observer will see the collapse to both the
horizon and the classical singularity occur in a finite amount of time. Quantum
mechanically, we take primary interest in the behavior of the collapse near the
horizon and near the classical singularity from the point of view of both
asymptotic and infalling observers. In the absence of radiation and
fluctuations of the metric, quantum effects near the horizon do not change the
classical conclusions for an asymptotic observer. The most interesting quantum
mechanical effect comes in when investigating near the classical singularity.
Here, we find, that the quantum effects in this region are able to remove the
classical singularity at the origin, since the wave function is non-singular,
and is also displays non-local effects, which depend on the energy density of
the domain wall.
| [
{
"created": "Sat, 17 Oct 2015 00:45:15 GMT",
"version": "v1"
}
] | 2016-04-20 | [
[
"Greenwood",
"Eric",
""
]
] | We investigate the gravitational collapse of a non-rotating $n$-dimensional BTZ black hole in AdS space in the context of both classical and quantum mechanics. This is done by first deriving the conserved mass of a "spherically" symmetric domain wall, which is taken as the classical Hamiltonian of the black hole. Upon deriving the conserved mass, we also point out that, for a "spherically" symmetric shell, there is an easy and straight-forward way of determining the conserved mass, which is related to the proper time derivative of the interior and exterior times. This method for determining the conserved mass is generic to any situation (i.e. any equation of state), since it only depends on the energy per unit area, $\sigma$, of the shell. Classically, we show that the time taken for gravitational collapse follows that of the typical formation of a black hole via gravitational collapse, that is, an asymptotic observer will see that the collapse takes an infinite amount of time to occur, while an infalling observer will see the collapse to both the horizon and the classical singularity occur in a finite amount of time. Quantum mechanically, we take primary interest in the behavior of the collapse near the horizon and near the classical singularity from the point of view of both asymptotic and infalling observers. In the absence of radiation and fluctuations of the metric, quantum effects near the horizon do not change the classical conclusions for an asymptotic observer. The most interesting quantum mechanical effect comes in when investigating near the classical singularity. Here, we find, that the quantum effects in this region are able to remove the classical singularity at the origin, since the wave function is non-singular, and is also displays non-local effects, which depend on the energy density of the domain wall. |
0912.2461 | L. C. Garcia de Andrade | L Garcia de Andrade | Mean-field cosmological dynamo curvature vs turbulence spectrum in
Riemannian space | Departamento de Fisica Teorica-IF-UERJ-Rio-RJ-Brasil | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Previous attempts for building a cosmic dynamo including preheating in
inflationary universes [Bassett et al Phys Rev (2001)] has not included mean
field dynamos. Here, a mean field dynamo in cosmic scales on a Riemannian
spatial cosmological section background, is set up. When magnetic fields and
flow velocities are parallel propagated along the Riemannian space dynamo
action is obtained. Turbulent diffusivity ${\beta}$ is coupled with the Ricci
magnetic curvature, as in Marklund and Clarkson [MNRAS (2005)], GR-MHD dynamo
equation. Mean electric field possesses an extra term due to Ricci tensor
coupling with magnetic vector potential in Ohm's law. Goedel universe induces a
mean field dynamo growth rate ${\gamma}=2{\omega}^{2}{\beta}$. In this frame
kinetic helicity vanishes. By considering a universe vorticity,
${\omega}\approx{10^{-16}s^{-1}}$ for galactic dynamos, thus
${\gamma}=2.10^{-32}{\beta}$, and since ${\beta}\approx{10^{26}cm^{2}s^{-1}}$,
the growth rate ${\gamma}\approx{10^{-6}s^{-1}}$. In non-comoving the magnetic
field is expressed as
$B\approx{\sqrt{\frac{2{\beta}}{\gamma}}{\times}10^{-6}G}\approx{10^{10}G}$ a
magnetic field found in the nucleosynthesis era. The Ricci scalar turbulence
spectrum of the cosmic dynamos is computed from the GR-MHD dynamo equation. By
analyzing the Fourier modes of the Ricci scalar, one shows that the energy
spectrum of the curvature turbulent dynamo is similar to the Kolmogorov
spectrum. Similar enhancements of turbulence in Friedmann cosmology have been
obtained by Brandenburg et al [Phys Rev D (1997)].
| [
{
"created": "Sat, 12 Dec 2009 23:08:07 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Dec 2009 02:33:50 GMT",
"version": "v2"
},
{
"created": "Thu, 31 Dec 2009 02:41:18 GMT",
"version": "v3"
}
] | 2009-12-31 | [
[
"de Andrade",
"L Garcia",
""
]
] | Previous attempts for building a cosmic dynamo including preheating in inflationary universes [Bassett et al Phys Rev (2001)] has not included mean field dynamos. Here, a mean field dynamo in cosmic scales on a Riemannian spatial cosmological section background, is set up. When magnetic fields and flow velocities are parallel propagated along the Riemannian space dynamo action is obtained. Turbulent diffusivity ${\beta}$ is coupled with the Ricci magnetic curvature, as in Marklund and Clarkson [MNRAS (2005)], GR-MHD dynamo equation. Mean electric field possesses an extra term due to Ricci tensor coupling with magnetic vector potential in Ohm's law. Goedel universe induces a mean field dynamo growth rate ${\gamma}=2{\omega}^{2}{\beta}$. In this frame kinetic helicity vanishes. By considering a universe vorticity, ${\omega}\approx{10^{-16}s^{-1}}$ for galactic dynamos, thus ${\gamma}=2.10^{-32}{\beta}$, and since ${\beta}\approx{10^{26}cm^{2}s^{-1}}$, the growth rate ${\gamma}\approx{10^{-6}s^{-1}}$. In non-comoving the magnetic field is expressed as $B\approx{\sqrt{\frac{2{\beta}}{\gamma}}{\times}10^{-6}G}\approx{10^{10}G}$ a magnetic field found in the nucleosynthesis era. The Ricci scalar turbulence spectrum of the cosmic dynamos is computed from the GR-MHD dynamo equation. By analyzing the Fourier modes of the Ricci scalar, one shows that the energy spectrum of the curvature turbulent dynamo is similar to the Kolmogorov spectrum. Similar enhancements of turbulence in Friedmann cosmology have been obtained by Brandenburg et al [Phys Rev D (1997)]. |
gr-qc/9604001 | Alan Rendall | Alan D. Rendall | An introduction to the Einstein-Vlasov system | 36 pages. Lectures given at the Banach centre, Warsaw, March 1996 | null | null | AEI 005 | gr-qc | null | These lectures are designed to provide a general introduction to the
Einstein-Vlasov system and to the global Cauchy problem for these equations. To
start with some general facts are collected and a local existence theorem for
the Cauchy problem stated. Next the case of spherically symmetric
asymptotically flat solutions is examined in detail. The approach taken, using
maximal-isotropic coordinates, is new. It is shown that if a singularity occurs
in the time evolution of spherically symmetric initial data, the first
singularity (as measured by a maximal time coordinate) occurs at the centre.
Then it is shown that for small initial data the solution exists globally in
time and is geodesically complete. Finally, the proof of the general local
existence theorem is sketched. This is intended to be an informal introduction
to some of the ideas which are important in proving such theorems rather than a
formal proof.
| [
{
"created": "Mon, 1 Apr 1996 08:54:09 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Rendall",
"Alan D.",
""
]
] | These lectures are designed to provide a general introduction to the Einstein-Vlasov system and to the global Cauchy problem for these equations. To start with some general facts are collected and a local existence theorem for the Cauchy problem stated. Next the case of spherically symmetric asymptotically flat solutions is examined in detail. The approach taken, using maximal-isotropic coordinates, is new. It is shown that if a singularity occurs in the time evolution of spherically symmetric initial data, the first singularity (as measured by a maximal time coordinate) occurs at the centre. Then it is shown that for small initial data the solution exists globally in time and is geodesically complete. Finally, the proof of the general local existence theorem is sketched. This is intended to be an informal introduction to some of the ideas which are important in proving such theorems rather than a formal proof. |
1007.1358 | M. D. Maia | M. D. Maia | Gravitational Waves from Coalescing Binary Sources | 4 pages, awarded a honorable mention from the Gravity Research
Foundation 2010 | Int.J.Mod.Phys.D19:2295-2298,2010 | 10.1142/S0218271810018499 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Coalescing binary systems (eg pulsars, neutron stars and black holes) are the
most likely sources of gravitational radiation, yet to be detected on or near
Earth, where the local gravitational field is negligible and the Poincar\'e
symmetry rules. On the other hand, the general theory of gravitational waves
emitted by axially symmetric rotating sources predicts the existence of a
non-vanishing news function. The existence of such function implies that, for a
distant observer, the asymptotic group of isometries, the BMS group, has a
translational symmetry that depends on the orbit periodicity of the source,
thus breaking the isotropy o the Poincar\'e translations. These results suggest
the application of the asymptotic BMS-covariant wave equation to obtain a
proper theoretical basis for the gravitational waves observations.
| [
{
"created": "Thu, 8 Jul 2010 12:44:30 GMT",
"version": "v1"
}
] | 2011-01-25 | [
[
"Maia",
"M. D.",
""
]
] | Coalescing binary systems (eg pulsars, neutron stars and black holes) are the most likely sources of gravitational radiation, yet to be detected on or near Earth, where the local gravitational field is negligible and the Poincar\'e symmetry rules. On the other hand, the general theory of gravitational waves emitted by axially symmetric rotating sources predicts the existence of a non-vanishing news function. The existence of such function implies that, for a distant observer, the asymptotic group of isometries, the BMS group, has a translational symmetry that depends on the orbit periodicity of the source, thus breaking the isotropy o the Poincar\'e translations. These results suggest the application of the asymptotic BMS-covariant wave equation to obtain a proper theoretical basis for the gravitational waves observations. |
gr-qc/0210088 | Makoto Narita | Makoto Narita | On the existence of global solutions for $T^{3}$-Gowdy spacetimes with
stringy matter | 10 pages, to appear in Classical and Quantum Gravity | Class.Quant.Grav. 19 (2002) 6279-6288 | 10.1088/0264-9381/19/24/301 | null | gr-qc math-ph math.AP math.MP | null | We show a global existence theorem for Einstein-matter equations of
$T^{3}$-Gowdy symmetric spacetimes with stringy matter. The areal time
coordinate is used. It is shown that this spacetime has a crushing singularity
into the past. From these results we can show that the spacetime is foliated by
compact hypersurfaces of constant mean curvature.
| [
{
"created": "Fri, 25 Oct 2002 09:58:30 GMT",
"version": "v1"
}
] | 2022-05-04 | [
[
"Narita",
"Makoto",
""
]
] | We show a global existence theorem for Einstein-matter equations of $T^{3}$-Gowdy symmetric spacetimes with stringy matter. The areal time coordinate is used. It is shown that this spacetime has a crushing singularity into the past. From these results we can show that the spacetime is foliated by compact hypersurfaces of constant mean curvature. |
1202.2788 | Francesco Salemi | the LIGO Scientific Collaboration, the Virgo Collaboration: J. Abadie,
B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese,
C. Adams, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B.
Allen, E. Amador Ceron, D. Amariutei, S. B. Anderson, W. G. Anderson, K.
Arai, M. A. Arain, M. C. Araya, S. M. Aston, P. Astone, D. Atkinson, P.
Aufmuth, C. Aulbert, B. E. Aylott, S. Babak, P. Baker, G. Ballardin, S.
Ballmer, J. C. B. Barayoga, D. Barker, F. Barone, B. Barr, L. Barsotti, M.
Barsuglia, M. A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, A. Basti, J.
Batch, J. Bauchrowitz, Th. S. Bauer, M. Bebronne, D. Beck, B. Behnke, M.
Bejger, M.G. Beker, A. S. Bell, A. Belletoile, I. Belopolski, M. Benacquista,
J. M. Berliner, A. Bertolini, J. Betzwieser, N. Beveridge, P. T. Beyersdorf,
I. A. Bilenko, G. Billingsley, J. Birch, R. Biswas, M. Bitossi, M. A.
Bizouard, E. Black, J. K. Blackburn, L. Blackburn, D. Blair, B. Bland, M.
Blom, O. Bock, T. P. Bodiya, C. Bogan, R. Bondarescu, F. Bondu, L. Bonelli,
R. Bonnand, R. Bork, M. Born, V. Boschi, S. Bose, L. Bosi, B. Bouhou, S.
Braccini, C. Bradaschia, P. R. Brady, V. B. Braginsky, M. Branchesi, J. E.
Brau, J. Breyer, T. Briant, D. O. Bridges, A. Brillet, M. Brinkmann, V.
Brisson, M. Britzger, A. F. Brooks, D. A. Brown, T. Bulik, H. J. Bulten, A.
Buonanno, J. Burguet-Castell, D. Buskulic, C. Buy, R. L. Byer, L. Cadonati,
G. Cagnoli, E. Calloni, J. B. Camp, P. Campsie, J. Cannizzo, K. Cannon, B.
Canuel, J. Cao, C. D. Capano, F. Carbognani, L. Carbone, S. Caride, S.
Caudill, M. Cavaglia, F. Cavalier, R. Cavalieri, G. Cella, C. Cepeda, E.
Cesarini, O. Chaibi, T. Chalermsongsak, P. Charlton, E. Chassande-Mottin, S.
Chelkowski, W. Chen, X. Chen, Y. Chen, A. Chincarini, A. Chiummo, H. Cho, J.
Chow, N. Christensen, S. S. Y. Chua, C. T. Y. Chung, S. Chung, G. Ciani, D.
E. Clark, J. Clark, J. H. Clayton, F. Cleva, E. Coccia, P.-F. Cohadon, C. N.
Colacino, J. Colas, A. Colla, M. Colombini, A. Conte, R. Conte, D. Cook, T.
R. Corbitt, M. Cordier, N. Cornish, A. Corsi, C. A. Costa, M. Coughlin, J.-P.
Coulon, P. Couvares, D. M. Coward, M. Cowart, D. C. Coyne, J. D. E.
Creighton, T. D. Creighton, A. M. Cruise, A. Cumming, L. Cunningham, E.
Cuoco, R. M. Cutler, K. Dahl, S. L. Danilishin, R. Dannenberg, S. D'Antonio,
K. Danzmann, V. Dattilo, B. Daudert, H. Daveloza, M. Davier, E. J. Daw, R.
Day, T. Dayanga, R. De Rosa, D. DeBra, G. Debreczeni, W. Del Pozzo, M. del
Prete, T. Dent, V. Dergachev, R. DeRosa, R. DeSalvo, S. Dhurandhar, L. Di
Fiore, A. Di Lieto, I. Di Palma, M. Di Paolo Emilio, A. Di Virgilio, M. Diaz,
A. Dietz, F. Donovan, K. L. Dooley, M. Drago, R. W. P. Drever, J. C.
Driggers, Z. Du, J.-C. Dumas, T. Eberle, M. Edgar, M. Edwards, A. Effler, P.
Ehrens, G. Endroczi, R. Engel, T. Etzel, K. Evans, M. Evans, T. Evans, M.
Factourovich, V. Fafone, S. Fairhurst, Y. Fan, B. F. Farr, D. Fazi, H.
Fehrmann, D. Feldbaum, F. Feroz, I. Ferrante, F. Fidecaro, L. S. Finn, I.
Fiori, R. P. Fisher, R. Flaminio, M. Flanigan, S. Foley, E. Forsi, L. A.
Forte, N. Fotopoulos, J.-D. Fournier, J. Franc, S. Frasca, F. Frasconi, M.
Frede, M. Frei, Z. Frei, A. Freise, R. Frey, T. T. Fricke, D. Friedrich, P.
Fritschel, V. V. Frolov, M.-K. Fujimoto, P. J. Fulda, M. Fyffe, J. Gair, M.
Galimberti, L. Gammaitoni, J. Garcia, F. Garufi, M. E. Gaspar, G. Gemme, R.
Geng, E. Genin, A. Gennai, L. A. Gergely, S. Ghosh, J. A. Giaime, S.
Giampanis, K. D. Giardina, A. Giazotto, S. Gil, C. Gill, J. Gleason, E.
Goetz, L. M. Goggin, G. Gonzalez, M. L. Gorodetsky, S. Gossler, R. Gouaty, C.
Graef, P. B. Graff, M. Granata, A. Grant, S. Gras, C. Gray, N. Gray, R. J. S.
Greenhalgh, A. M. Gretarsson, C. Greverie, R. Grosso, H. Grote, S. Grunewald,
G. M. Guidi, R. Gupta, E. K. Gustafson, R. Gustafson, T. Ha, J. M. Hallam, D.
Hammer, G. Hammond, J. Hanks, C. Hanna, J. Hanson, A. Hardt, J. Harms, G. M.
Harry, I. W. Harry, E. D. Harstad, M. T. Hartman, K. Haughian, K. Hayama,
J.-F. Hayau, J. Heefner, A. Heidmann, M. C. Heintze, H. Heitmann, P. Hello,
M. A. Hendry, I. S. Heng, A. W. Heptonstall, V. Herrera, M. Hewitson, S.
Hild, D. Hoak, K. A. Hodge, K. Holt, M. Holtrop, T. Hong, S. Hooper, D. J.
Hosken, J. Hough, E. J. Howell, B. Hughey, S. Husa, S. H. Huttner, R. Inta,
T. Isogai, A. Ivanov, K. Izumi, M. Jacobson, E. James, Y. J. Jang, P.
Jaranowski, E. Jesse, W. W. Johnson, D. I. Jones, G. Jones, R. Jones, L. Ju,
P. Kalmus, V. Kalogera, S. Kandhasamy, G. Kang, J. B. Kanner, R. Kasturi, E.
Katsavounidis, W. Katzman, H. Kaufer, K. Kawabe, S. Kawamura, F. Kawazoe, D.
Kelley, W. Kells, D. G. Keppel, Z. Keresztes, A. Khalaidovski, F. Y. Khalili,
E. A. Khazanov, B. Kim, C. Kim, H. Kim, K. Kim, N. Kim, Y. -M. Kim, P. J.
King, D. L. Kinzel, J. S. Kissel, S. Klimenko, K. Kokeyama, V. Kondrashov, S.
Koranda, W. Z. Korth, I. Kowalska, D. Kozak, O. Kranz, V. Kringel, S.
Krishnamurthy, B. Krishnan, A. Krolak, G. Kuehn, R. Kumar, P. Kwee, P. K.
Lam, M. Landry, B. Lantz, N. Lastzka, C. Lawrie, A. Lazzarini, P. Leaci, C.
H. Lee, H. K. Lee, H. M. Lee, J. R. Leong, I. Leonor, N. Leroy, N. Letendre,
J. Li, T. G. F. Li, N. Liguori, P. E. Lindquist, Y. Liu, Z. Liu, N. A.
Lockerbie, D. Lodhia, M. Lorenzini, V. Loriette, M. Lormand, G. Losurdo, J.
Lough, J. Luan, M. Lubinski, H. Luck, A. P. Lundgren, E. Macdonald, B.
Machenschalk, M. MacInnis, D. M. Macleod, M. Mageswaran, K. Mailand, E.
Majorana, I. Maksimovic, N. Man, I. Mandel, V. Mandic, M. Mantovani, A.
Marandi, F. Marchesoni, F. Marion, S. Marka, Z. Marka, A. Markosyan, E.
Maros, J. Marque, F. Martelli, I. W. Martin, R. M. Martin, J. N. Marx, K.
Mason, A. Masserot, F. Matichard, L. Matone, R. A. Matzner, N. Mavalvala, G.
Mazzolo, R. McCarthy, D. E. McClelland, S. C. McGuire, G. McIntyre, J.
McIver, D. J. A. McKechan, S. McWilliams, G. D. Meadors, M. Mehmet, T. Meier,
A. Melatos, A. C. Melissinos, G. Mendell, R. A. Mercer, S. Meshkov, C.
Messenger, M. S. Meyer, C. Michel, L. Milano, J. Miller, Y. Minenkov, V. P.
Mitrofanov, G. Mitselmakher, R. Mittleman, O. Miyakawa, B. Moe, M. Mohan, S.
D. Mohanty, S. R. P. Mohapatra, G. Moreno, N. Morgado, A. Morgia, T. Mori, S.
R. Morriss, S. Mosca, K. Mossavi, B. Mours, C. M. Mow-Lowry, C. L. Mueller,
G. Mueller, S. Mukherjee, A. Mullavey, H. Muller-Ebhardt, J. Munch, D.
Murphy, P. G. Murray, A. Mytidis, T. Nash, L. Naticchioni, V. Necula, J.
Nelson, G. Newton, T. Nguyen, A. Nishizawa, A. Nitz, F. Nocera, D. Nolting,
M. E. Normandin, L. Nuttall, E. Ochsner, J. O'Dell, E. Oelker, G. H. Ogin, J.
J. Oh, S. H. Oh, B. O'Reilly, R. O'Shaughnessy, C. Osthelder, C. D. Ott, D.
J. Ottaway, R. S. Ottens, H. Overmier, B. J. Owen, A. Page, G. Pagliaroli, L.
Palladino, C. Palomba, Y. Pan, C. Pankow, F. Paoletti, M. A. Papa, M. Parisi,
A. Pasqualetti, R. Passaquieti, D. Passuello, P. Patel, M. Pedraza, P.
Peiris, L. Pekowsky, S. Penn, A. Perreca, G. Persichetti, M. Phelps, M.
Pickenpack, F. Piergiovanni, M. Pietka, L. Pinard, I. M. Pinto, M. Pitkin, H.
J. Pletsch, M. V. Plissi, R. Poggiani, J. Pold, F. Postiglione, M. Prato, V.
Predoi, T. Prestegard, L. R. Price, M. Prijatelj, M. Principe, S. Privitera,
R. Prix, G. A. Prodi, L. G. Prokhorov, O. Puncken, M. Punturo, P. Puppo, V.
Quetschke, R. Quitzow-James, F. J. Raab, D. S. Rabeling, I. Racz, H. Radkins,
P. Raffai, M. Rakhmanov, B. Rankins, P. Rapagnani, V. Raymond, V. Re, K.
Redwine, C. M. Reed, T. Reed, T. Regimbau, S. Reid, D. H. Reitze, F. Ricci,
R. Riesen, K. Riles, N. A. Robertson, F. Robinet, C. Robinson, E. L.
Robinson, A. Rocchi, S. Roddy, C. Rodriguez, M. Rodruck, L. Rolland, J. G.
Rollins, J. D. Romano, R. Romano, J. H. Romie, D. Rosinska, C. Rover, S.
Rowan, A. Rudiger, P. Ruggi, K. Ryan, P. Sainathan, F. Salemi, L. Sammut, V.
Sandberg, V. Sannibale, L. Santamaria, I. Santiago-Prieto, G. Santostasi, B.
Sassolas, B. S. Sathyaprakash, S. Sato, P. R. Saulson, R. L. Savage, R.
Schilling, R. Schnabel, R. M. S. Schofield, E. Schreiber, B. Schulz, B. F.
Schutz, P. Schwinberg, J. Scott, S. M. Scott, F. Seifert, D. Sellers, D.
Sentenac, A. Sergeev, D. A. Shaddock, M. Shaltev, B. Shapiro, P. Shawhan, D.
H. Shoemaker, A. Sibley, X. Siemens, D. Sigg, A. Singer, L. Singer, A. M.
Sintes, G. R. Skelton, B. J. J. Slagmolen, J. Slutsky, J. R. Smith, M. R.
Smith, R. J. E. Smith, N. D. Smith-Lefebvre, K. Somiya, B. Sorazu, J. Soto,
F. C. Speirits, L. Sperandio, M. Stefszky, A. J. Stein, L. C. Stein, E.
Steinert, J. Steinlechner, S. Steinlechner, S. Steplewski, A. Stochino, R.
Stone, K. A. Strain, S. E. Strigin, A. S. Stroeer, R. Sturani, A. L. Stuver,
T. Z. Summerscales, M. Sung, S. Susmithan, P. J. Sutton, B. Swinkels, M.
Tacca, L. Taffarello, D. Talukder, D. B. Tanner, S. P. Tarabrin, J. R.
Taylor, R. Taylor, P. Thomas, K. A. Thorne, K. S. Thorne, E. Thrane, A.
Thuring, K. V. Tokmakov, C. Tomlinson, A. Toncelli, M. Tonelli, O. Torre, C.
Torres, C. I. Torrie, E. Tournefier, F. Travasso, G. Traylor, K. Tseng, E.
Tucker, D. Ugolini, H. Vahlbruch, G. Vajente, J. F. J. van den Brand, C. Van
Den Broeck, S. van der Putten, A. A. van Veggel, S. Vass, M. Vasuth, R.
Vaulin, M. Vavoulidis, A. Vecchio, G. Vedovato, J. Veitch, P. J. Veitch, C.
Veltkamp, D. Verkindt, F. Vetrano, A. Vicere, A. E. Villar, J.-Y. Vinet, S.
Vitale, S. Vitale, H. Vocca, C. Vorvick, S. P. Vyatchanin, A. Wade, L. Wade,
M. Wade, S. J. Waldman, L. Wallace, Y. Wan, M. Wang, X. Wang, Z. Wang, A.
Wanner, R. L. Ward, M. Was, M. Weinert, A. J. Weinstein, R. Weiss, L. Wen, P.
Wessels, M. West, T. Westphal, K. Wette, J. T. Whelan, S. E. Whitcomb, D. J.
White, B. F. Whiting, C. Wilkinson, P. A. Willems, L. Williams, R. Williams,
B. Willke, L. Winkelmann, W. Winkler, C. C. Wipf, A. G. Wiseman, H. Wittel,
G. Woan, R. Wooley, J. Worden, I. Yakushin, H. Yamamoto, K. Yamamoto, K.
Yamamoto, C. C. Yancey, H. Yang, D. Yeaton-Massey, S. Yoshida, P. Yu, M.
Yvert, A. Zadrozny, M. Zanolin, J.-P. Zendri, F. Zhang, L. Zhang, W. Zhang,
C. Zhao, N. Zotov, M. E. Zucker, J. Zweizig | All-sky search for gravitational-wave bursts in the second joint
LIGO-Virgo run | 15 pages, 7 figures: data for plots and archived public version at
https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=70814&version=19, see
also the public announcement at
http://www.ligo.org/science/Publication-S6BurstAllSky/ | null | 10.1103/PhysRevD.85.122007 | LIGO-P1100118 | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present results from a search for gravitational-wave bursts in the data
collected by the LIGO and Virgo detectors between July 7, 2009 and October 20,
2010: data are analyzed when at least two of the three LIGO-Virgo detectors are
in coincident operation, with a total observation time of 207 days. The
analysis searches for transients of duration < 1 s over the frequency band
64-5000 Hz, without other assumptions on the signal waveform, polarization,
direction or occurrence time. All identified events are consistent with the
expected accidental background. We set frequentist upper limits on the rate of
gravitational-wave bursts by combining this search with the previous LIGO-Virgo
search on the data collected between November 2005 and October 2007. The upper
limit on the rate of strong gravitational-wave bursts at the Earth is 1.3
events per year at 90% confidence. We also present upper limits on source rate
density per year and Mpc^3 for sample populations of standard-candle sources.
As in the previous joint run, typical sensitivities of the search in terms of
the root-sum-squared strain amplitude for these waveforms lie in the range 5
10^-22 Hz^-1/2 to 1 10^-20 Hz^-1/2. The combination of the two joint runs
entails the most sensitive all-sky search for generic gravitational-wave bursts
and synthesizes the results achieved by the initial generation of
interferometric detectors.
| [
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"C.",
""
],
[
"Robinson",
"E. L.",
""
],
[
"Rocchi",
"A.",
""
],
[
"Roddy",
"S.",
""
],
[
"Rodriguez",
"C.",
""
],
[
"Rodruck",
"M.",
""
],
[
"Rolland",
"L.",
""
],
[
"Rollins",
"J. G.",
""
],
[
"Romano",
"J. D.",
""
],
[
"Romano",
"R.",
""
],
[
"Romie",
"J. H.",
""
],
[
"Rosinska",
"D.",
""
],
[
"Rover",
"C.",
""
],
[
"Rowan",
"S.",
""
],
[
"Rudiger",
"A.",
""
],
[
"Ruggi",
"P.",
""
],
[
"Ryan",
"K.",
""
],
[
"Sainathan",
"P.",
""
],
[
"Salemi",
"F.",
""
],
[
"Sammut",
"L.",
""
],
[
"Sandberg",
"V.",
""
],
[
"Sannibale",
"V.",
""
],
[
"Santamaria",
"L.",
""
],
[
"Santiago-Prieto",
"I.",
""
],
[
"Santostasi",
"G.",
""
],
[
"Sassolas",
"B.",
""
],
[
"Sathyaprakash",
"B. S.",
""
],
[
"Sato",
"S.",
""
],
[
"Saulson",
"P. R.",
""
],
[
"Savage",
"R. L.",
""
],
[
"Schilling",
"R.",
""
],
[
"Schnabel",
"R.",
""
],
[
"Schofield",
"R. M. S.",
""
],
[
"Schreiber",
"E.",
""
],
[
"Schulz",
"B.",
""
],
[
"Schutz",
"B. F.",
""
],
[
"Schwinberg",
"P.",
""
],
[
"Scott",
"J.",
""
],
[
"Scott",
"S. M.",
""
],
[
"Seifert",
"F.",
""
],
[
"Sellers",
"D.",
""
],
[
"Sentenac",
"D.",
""
],
[
"Sergeev",
"A.",
""
],
[
"Shaddock",
"D. A.",
""
],
[
"Shaltev",
"M.",
""
],
[
"Shapiro",
"B.",
""
],
[
"Shawhan",
"P.",
""
],
[
"Shoemaker",
"D. H.",
""
],
[
"Sibley",
"A.",
""
],
[
"Siemens",
"X.",
""
],
[
"Sigg",
"D.",
""
],
[
"Singer",
"A.",
""
],
[
"Singer",
"L.",
""
],
[
"Sintes",
"A. M.",
""
],
[
"Skelton",
"G. R.",
""
],
[
"Slagmolen",
"B. J. J.",
""
],
[
"Slutsky",
"J.",
""
],
[
"Smith",
"J. R.",
""
],
[
"Smith",
"M. R.",
""
],
[
"Smith",
"R. J. E.",
""
],
[
"Smith-Lefebvre",
"N. D.",
""
],
[
"Somiya",
"K.",
""
],
[
"Sorazu",
"B.",
""
],
[
"Soto",
"J.",
""
],
[
"Speirits",
"F. C.",
""
],
[
"Sperandio",
"L.",
""
],
[
"Stefszky",
"M.",
""
],
[
"Stein",
"A. J.",
""
],
[
"Stein",
"L. C.",
""
],
[
"Steinert",
"E.",
""
],
[
"Steinlechner",
"J.",
""
],
[
"Steinlechner",
"S.",
""
],
[
"Steplewski",
"S.",
""
],
[
"Stochino",
"A.",
""
],
[
"Stone",
"R.",
""
],
[
"Strain",
"K. A.",
""
],
[
"Strigin",
"S. E.",
""
],
[
"Stroeer",
"A. S.",
""
],
[
"Sturani",
"R.",
""
],
[
"Stuver",
"A. L.",
""
],
[
"Summerscales",
"T. Z.",
""
],
[
"Sung",
"M.",
""
],
[
"Susmithan",
"S.",
""
],
[
"Sutton",
"P. J.",
""
],
[
"Swinkels",
"B.",
""
],
[
"Tacca",
"M.",
""
],
[
"Taffarello",
"L.",
""
],
[
"Talukder",
"D.",
""
],
[
"Tanner",
"D. B.",
""
],
[
"Tarabrin",
"S. P.",
""
],
[
"Taylor",
"J. R.",
""
],
[
"Taylor",
"R.",
""
],
[
"Thomas",
"P.",
""
],
[
"Thorne",
"K. A.",
""
],
[
"Thorne",
"K. S.",
""
],
[
"Thrane",
"E.",
""
],
[
"Thuring",
"A.",
""
],
[
"Tokmakov",
"K. V.",
""
],
[
"Tomlinson",
"C.",
""
],
[
"Toncelli",
"A.",
""
],
[
"Tonelli",
"M.",
""
],
[
"Torre",
"O.",
""
],
[
"Torres",
"C.",
""
],
[
"Torrie",
"C. I.",
""
],
[
"Tournefier",
"E.",
""
],
[
"Travasso",
"F.",
""
],
[
"Traylor",
"G.",
""
],
[
"Tseng",
"K.",
""
],
[
"Tucker",
"E.",
""
],
[
"Ugolini",
"D.",
""
],
[
"Vahlbruch",
"H.",
""
],
[
"Vajente",
"G.",
""
],
[
"Brand",
"J. F. J. van den",
""
],
[
"Broeck",
"C. Van Den",
""
],
[
"van der Putten",
"S.",
""
],
[
"van Veggel",
"A. A.",
""
],
[
"Vass",
"S.",
""
],
[
"Vasuth",
"M.",
""
],
[
"Vaulin",
"R.",
""
],
[
"Vavoulidis",
"M.",
""
],
[
"Vecchio",
"A.",
""
],
[
"Vedovato",
"G.",
""
],
[
"Veitch",
"J.",
""
],
[
"Veitch",
"P. J.",
""
],
[
"Veltkamp",
"C.",
""
],
[
"Verkindt",
"D.",
""
],
[
"Vetrano",
"F.",
""
],
[
"Vicere",
"A.",
""
],
[
"Villar",
"A. E.",
""
],
[
"Vinet",
"J. -Y.",
""
],
[
"Vitale",
"S.",
""
],
[
"Vitale",
"S.",
""
],
[
"Vocca",
"H.",
""
],
[
"Vorvick",
"C.",
""
],
[
"Vyatchanin",
"S. P.",
""
],
[
"Wade",
"A.",
""
],
[
"Wade",
"L.",
""
],
[
"Wade",
"M.",
""
],
[
"Waldman",
"S. J.",
""
],
[
"Wallace",
"L.",
""
],
[
"Wan",
"Y.",
""
],
[
"Wang",
"M.",
""
],
[
"Wang",
"X.",
""
],
[
"Wang",
"Z.",
""
],
[
"Wanner",
"A.",
""
],
[
"Ward",
"R. L.",
""
],
[
"Was",
"M.",
""
],
[
"Weinert",
"M.",
""
],
[
"Weinstein",
"A. J.",
""
],
[
"Weiss",
"R.",
""
],
[
"Wen",
"L.",
""
],
[
"Wessels",
"P.",
""
],
[
"West",
"M.",
""
],
[
"Westphal",
"T.",
""
],
[
"Wette",
"K.",
""
],
[
"Whelan",
"J. T.",
""
],
[
"Whitcomb",
"S. E.",
""
],
[
"White",
"D. J.",
""
],
[
"Whiting",
"B. F.",
""
],
[
"Wilkinson",
"C.",
""
],
[
"Willems",
"P. A.",
""
],
[
"Williams",
"L.",
""
],
[
"Williams",
"R.",
""
],
[
"Willke",
"B.",
""
],
[
"Winkelmann",
"L.",
""
],
[
"Winkler",
"W.",
""
],
[
"Wipf",
"C. C.",
""
],
[
"Wiseman",
"A. G.",
""
],
[
"Wittel",
"H.",
""
],
[
"Woan",
"G.",
""
],
[
"Wooley",
"R.",
""
],
[
"Worden",
"J.",
""
],
[
"Yakushin",
"I.",
""
],
[
"Yamamoto",
"H.",
""
],
[
"Yamamoto",
"K.",
""
],
[
"Yamamoto",
"K.",
""
],
[
"Yancey",
"C. C.",
""
],
[
"Yang",
"H.",
""
],
[
"Yeaton-Massey",
"D.",
""
],
[
"Yoshida",
"S.",
""
],
[
"Yu",
"P.",
""
],
[
"Yvert",
"M.",
""
],
[
"Zadrozny",
"A.",
""
],
[
"Zanolin",
"M.",
""
],
[
"Zendri",
"J. -P.",
""
],
[
"Zhang",
"F.",
""
],
[
"Zhang",
"L.",
""
],
[
"Zhang",
"W.",
""
],
[
"Zhao",
"C.",
""
],
[
"Zotov",
"N.",
""
],
[
"Zucker",
"M. E.",
""
],
[
"Zweizig",
"J.",
""
]
] | We present results from a search for gravitational-wave bursts in the data collected by the LIGO and Virgo detectors between July 7, 2009 and October 20, 2010: data are analyzed when at least two of the three LIGO-Virgo detectors are in coincident operation, with a total observation time of 207 days. The analysis searches for transients of duration < 1 s over the frequency band 64-5000 Hz, without other assumptions on the signal waveform, polarization, direction or occurrence time. All identified events are consistent with the expected accidental background. We set frequentist upper limits on the rate of gravitational-wave bursts by combining this search with the previous LIGO-Virgo search on the data collected between November 2005 and October 2007. The upper limit on the rate of strong gravitational-wave bursts at the Earth is 1.3 events per year at 90% confidence. We also present upper limits on source rate density per year and Mpc^3 for sample populations of standard-candle sources. As in the previous joint run, typical sensitivities of the search in terms of the root-sum-squared strain amplitude for these waveforms lie in the range 5 10^-22 Hz^-1/2 to 1 10^-20 Hz^-1/2. The combination of the two joint runs entails the most sensitive all-sky search for generic gravitational-wave bursts and synthesizes the results achieved by the initial generation of interferometric detectors. |
gr-qc/0104025 | David Apsel | David Apsel | Pulsars and Redshifts | 3 pages no figures | null | null | null | gr-qc astro-ph | null | Gravitational redshifts of neutron stars have a theoretical upper limit of
z=0.62. Also, it is generally believed that neutron stars have magnetic fields
on the order of ten to the twelfth to ten to the thirteenth G. A previously
predicted electromagnetic time dilation effect has been shown to correctly
predict decay lifetimes of muons bound to atomic nuclei. In this paper it is
shown that the electromagnetic time dilation effect, along with the
gravitational time dilation effect, can produce total neutron star redshifts
that are substantially larger than 0.62. For instance, the redshift can cutoff
radiation for B on the order of ten to the thirteenth G. Consequently, we can
have a neutron star that is unobservable except for localized surface regions
where the cutoff condition does not hold. Assuming coherent radiation, a
surface region of this kind that does not include the star's rotation axis will
emit a lighthouse type beam. Since the magnetic field in these regions will
usually be strong enough to cause significant redshifts, and there is no reason
to expect these regions to always be of constant size, shape, or field
strength, this model explains the predominance of radio waves, and the
existence of pulse variations, (e.g. nulling and drifting) in pulsars.
| [
{
"created": "Mon, 9 Apr 2001 14:34:55 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Apsel",
"David",
""
]
] | Gravitational redshifts of neutron stars have a theoretical upper limit of z=0.62. Also, it is generally believed that neutron stars have magnetic fields on the order of ten to the twelfth to ten to the thirteenth G. A previously predicted electromagnetic time dilation effect has been shown to correctly predict decay lifetimes of muons bound to atomic nuclei. In this paper it is shown that the electromagnetic time dilation effect, along with the gravitational time dilation effect, can produce total neutron star redshifts that are substantially larger than 0.62. For instance, the redshift can cutoff radiation for B on the order of ten to the thirteenth G. Consequently, we can have a neutron star that is unobservable except for localized surface regions where the cutoff condition does not hold. Assuming coherent radiation, a surface region of this kind that does not include the star's rotation axis will emit a lighthouse type beam. Since the magnetic field in these regions will usually be strong enough to cause significant redshifts, and there is no reason to expect these regions to always be of constant size, shape, or field strength, this model explains the predominance of radio waves, and the existence of pulse variations, (e.g. nulling and drifting) in pulsars. |
gr-qc/0609003 | Reinoud Slagter | Reinoud J. Slagter | On A 5-Dimensional Spinning Cosmic String | 15 pages 32 figures. Improvement of numerical solutions | null | null | null | gr-qc | null | We present a numerical solution of a stationary 5-dimensional spinning cosmic
string in the Einstein-Yang-Mills (EYM) model, where the extra bulk coordinate
$\psi$ is periodic. It turns out that when $g_{\psi\psi}$ approaches zero,
i.e., a closed time-like curve (CTC) would appear, the solution becomes
singular. When a negative cosmological constant is incorporated in the model,
the solution becomes regular everywhere with angle deficit$<2\pi$. However, the
cosmic string-like object has not all the desired asymptotic properties of the
counterpart Abelian Nielsen-Olesen string. When we use a two point boundary
value routine with the correct cosmic string features far from the core, then
again a negative $\Lambda$ results in an acceptable string-like solution.
We also investigated the possibility of a Gott space time structure of the
static 5D cosmic string. The matching condition yields no obstruction for an
effective angle deficit. Moreover, by considering the angular momentum in bulk
space, no helical structure of time is necessary. Two opposite moving 5D
strings could, in contrast with the 4D case, fulfil the Gott condition.
| [
{
"created": "Thu, 31 Aug 2006 21:55:05 GMT",
"version": "v1"
},
{
"created": "Sun, 2 Mar 2008 09:58:06 GMT",
"version": "v2"
}
] | 2008-03-03 | [
[
"Slagter",
"Reinoud J.",
""
]
] | We present a numerical solution of a stationary 5-dimensional spinning cosmic string in the Einstein-Yang-Mills (EYM) model, where the extra bulk coordinate $\psi$ is periodic. It turns out that when $g_{\psi\psi}$ approaches zero, i.e., a closed time-like curve (CTC) would appear, the solution becomes singular. When a negative cosmological constant is incorporated in the model, the solution becomes regular everywhere with angle deficit$<2\pi$. However, the cosmic string-like object has not all the desired asymptotic properties of the counterpart Abelian Nielsen-Olesen string. When we use a two point boundary value routine with the correct cosmic string features far from the core, then again a negative $\Lambda$ results in an acceptable string-like solution. We also investigated the possibility of a Gott space time structure of the static 5D cosmic string. The matching condition yields no obstruction for an effective angle deficit. Moreover, by considering the angular momentum in bulk space, no helical structure of time is necessary. Two opposite moving 5D strings could, in contrast with the 4D case, fulfil the Gott condition. |
gr-qc/9605022 | Alan Rendall | Alan D. Rendall | Existence of constant mean curvature foliations in spacetimes with
two-dimensional local symmetry | 22 pages | Commun.Math.Phys. 189 (1997) 145-164 | 10.1007/s002200050194 | null | gr-qc dg-ga math.DG | null | It is shown that in a class of maximal globally hyperbolic spacetimes
admitting two local Killing vectors, the past (defined with respect to an
appropriate time orientation) of any compact constant mean curvature
hypersurface can be covered by a foliation of compact constant mean curvature
hypersurfaces. Moreover, the mean curvature of the leaves of this foliation
takes on arbitrarily negative values and so the initial singularity in these
spacetimes is a crushing singularity. The simplest examples occur when the
spatial topology is that of a torus, with the standard global Killing vectors,
but more exotic topologies are also covered. In the course of the proof it is
shown that in this class of spacetimes a kind of positive mass theorem holds.
The symmetry singles out a compact surface passing through any given point of
spacetime and the Hawking mass of any such surface is non-negative. If the
Hawking mass of any one of these surfaces is zero then the entire spacetime is
flat.
| [
{
"created": "Fri, 10 May 1996 11:52:01 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Rendall",
"Alan D.",
""
]
] | It is shown that in a class of maximal globally hyperbolic spacetimes admitting two local Killing vectors, the past (defined with respect to an appropriate time orientation) of any compact constant mean curvature hypersurface can be covered by a foliation of compact constant mean curvature hypersurfaces. Moreover, the mean curvature of the leaves of this foliation takes on arbitrarily negative values and so the initial singularity in these spacetimes is a crushing singularity. The simplest examples occur when the spatial topology is that of a torus, with the standard global Killing vectors, but more exotic topologies are also covered. In the course of the proof it is shown that in this class of spacetimes a kind of positive mass theorem holds. The symmetry singles out a compact surface passing through any given point of spacetime and the Hawking mass of any such surface is non-negative. If the Hawking mass of any one of these surfaces is zero then the entire spacetime is flat. |
2203.14866 | Genly Le\'on | Genly Leon (Catolica del Norte U. and DUT, Durban), Andronikos
Paliathanasis (DUT, Durban, and Chile Austral U., Valdivia), Emmanuel N.
Saridakis (Athens Observ. and USTC, Hefei and CUST, SKLPDE and Hefei, CUST),
and Spyros Basilakos (Athens Observ., Athens Academy and European University
Cyprus) | Unified dark sectors in scalar-torsion theories of gravity | 12 pages, 4 figures | null | 10.1103/PhysRevD.106.024055 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a unified description of the matter and dark energy epochs, using
a class of scalar-torsion theories. We provide a Hamiltonian description, and
by applying Noether's theorem and by requiring the field equations to admit
linear-in-momentum conservation laws we obtain two specific classes of
scalar-field potentials. We extract analytic solutions and we perform a
detailed dynamical analysis. We show that the system possesses critical points
that correspond to scaling solutions in which the effective, total
equation-of-state parameter is close to zero and points in which it is equal to
the cosmological constant value $-1$. Therefore, during evolution, the Universe
remains for sufficiently long times at the epoch corresponding to dust-matter
domination, while at later times it enters the accelerated epoch and it
eventually results in the de Sitter phase. Finally, in contrast to other
unified scenarios, such as Chaplygin gas-based models as well as
Horndeski-based constructions, the present scenario is free from instabilities
and pathologies at the perturbative level.
| [
{
"created": "Mon, 28 Mar 2022 16:14:27 GMT",
"version": "v1"
}
] | 2022-08-17 | [
[
"Leon",
"Genly",
"",
"Catolica del Norte U. and DUT, Durban"
],
[
"Paliathanasis",
"Andronikos",
"",
"DUT, Durban, and Chile Austral U., Valdivia"
],
[
"Saridakis",
"Emmanuel N.",
"",
"Athens Observ. and USTC, Hefei and CUST, SKLPDE and Hefei, CUST"
],
[
"Basilakos",
"Spyros",
"",
"Athens Observ., Athens Academy and European University\n Cyprus"
]
] | We present a unified description of the matter and dark energy epochs, using a class of scalar-torsion theories. We provide a Hamiltonian description, and by applying Noether's theorem and by requiring the field equations to admit linear-in-momentum conservation laws we obtain two specific classes of scalar-field potentials. We extract analytic solutions and we perform a detailed dynamical analysis. We show that the system possesses critical points that correspond to scaling solutions in which the effective, total equation-of-state parameter is close to zero and points in which it is equal to the cosmological constant value $-1$. Therefore, during evolution, the Universe remains for sufficiently long times at the epoch corresponding to dust-matter domination, while at later times it enters the accelerated epoch and it eventually results in the de Sitter phase. Finally, in contrast to other unified scenarios, such as Chaplygin gas-based models as well as Horndeski-based constructions, the present scenario is free from instabilities and pathologies at the perturbative level. |
2403.13608 | Yong-Wan Kim | Soon-Tae Hong, Yong-Wan Kim, Young-Jai Park | Tidal effects based on GUP-induced effective metric | 13 pages, 9 figures, version to appear in Communications in
Theoretical Physics | null | 10.1088/1572-9494/ad51f0 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we study tidal forces in the Schwarzschild black hole whose
metric includes explicitly a generalized uncertainty principle (GUP) effect. We
also investigate interesting features of the geodesic equations and tidal
effects dependent on the GUP parameter $\alpha$ related to a minimum length.
Then, by solving geodesic deviation equations explicitly with appropriate
boundary conditions, we show that $\alpha$ in the effective metric affects both
the radial and angular components of the geodesic equation, particularly near
the singularities.
| [
{
"created": "Wed, 20 Mar 2024 13:59:23 GMT",
"version": "v1"
},
{
"created": "Sun, 2 Jun 2024 07:53:47 GMT",
"version": "v2"
}
] | 2024-06-04 | [
[
"Hong",
"Soon-Tae",
""
],
[
"Kim",
"Yong-Wan",
""
],
[
"Park",
"Young-Jai",
""
]
] | In this paper, we study tidal forces in the Schwarzschild black hole whose metric includes explicitly a generalized uncertainty principle (GUP) effect. We also investigate interesting features of the geodesic equations and tidal effects dependent on the GUP parameter $\alpha$ related to a minimum length. Then, by solving geodesic deviation equations explicitly with appropriate boundary conditions, we show that $\alpha$ in the effective metric affects both the radial and angular components of the geodesic equation, particularly near the singularities. |
1307.1422 | Richard Woodard | P. J. Mora (Florida), N. C. Tsamis (Crete) and R. P. Woodard (Florida) | Hartree Approximation to the One Loop Quantum Gravitational Correction
to the Graviton Mode Function on de Sitter | 23 pages, uses LaTeX2e, version 2 expanded (by 7 pages) for
publication to define the effective mode equation and compare the exact one
loop result for it with the Hartree approximation | JCAP 10 (2013) 018 | 10.1088/1475-7516/2013/10/018 | UFIFT-QG-13-04 | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the Hartree approximation to the Einstein equation on de Sitter
background to solve for the one loop correction to the graviton mode function.
This should give a reasonable approximation to how the ensemble of inflationary
gravitons affects a single external graviton. At late times we find that the
one loop correction to the plane wave mode function $u(\eta,k)$ goes like $G
H^2 \ln(a)/a^2$, where $a$ is the inflationary scale factor. One consequence is
that the one loop corrections to the "electric" components of the linearized
Weyl tensor grow compared to the tree order result.
| [
{
"created": "Thu, 4 Jul 2013 17:34:57 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Oct 2013 23:19:06 GMT",
"version": "v2"
}
] | 2013-10-15 | [
[
"Mora",
"P. J.",
"",
"Florida"
],
[
"Tsamis",
"N. C.",
"",
"Crete"
],
[
"Woodard",
"R. P.",
"",
"Florida"
]
] | We use the Hartree approximation to the Einstein equation on de Sitter background to solve for the one loop correction to the graviton mode function. This should give a reasonable approximation to how the ensemble of inflationary gravitons affects a single external graviton. At late times we find that the one loop correction to the plane wave mode function $u(\eta,k)$ goes like $G H^2 \ln(a)/a^2$, where $a$ is the inflationary scale factor. One consequence is that the one loop corrections to the "electric" components of the linearized Weyl tensor grow compared to the tree order result. |
2306.15486 | Boran Yesilyurt | C. Litos, R. P. Woodard, B. Yesilyurt | Large Inflationary Logarithms in a Nontrivial Nonlinear Sigma Model | 17 pages, 7 figures, uses LaTex 2e, Version 2 revised for publication
with 7 figures and length of 19 pages | Phys. Rev. D108 (2023) 065001 | 10.1103/PhysRevD.108.065001 | UFIFT-QG-23-07 | gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | Loops of inflationary gravitons are known to induce large temporal and
spatial logarithms which can cause perturbation theory to break down. Nonlinear
sigma models possess the same kind of derivative interactions and induce the
same sorts of large logarithms, without the complicated index structure and
potential gauge problem. Previous studies have examined models with zero field
space curvature which can be reduced to free field theories by local,
invertible field redefinitions. Here we study a model which cannot be so
reduced and still shows the same sorts of large logarithms. We compute the
evolution of the background at 1-loop and 2-loop orders, and we find the 1-loop
$\beta$ and $\gamma$ functions.
| [
{
"created": "Tue, 27 Jun 2023 14:08:23 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Sep 2023 02:25:40 GMT",
"version": "v2"
}
] | 2023-09-11 | [
[
"Litos",
"C.",
""
],
[
"Woodard",
"R. P.",
""
],
[
"Yesilyurt",
"B.",
""
]
] | Loops of inflationary gravitons are known to induce large temporal and spatial logarithms which can cause perturbation theory to break down. Nonlinear sigma models possess the same kind of derivative interactions and induce the same sorts of large logarithms, without the complicated index structure and potential gauge problem. Previous studies have examined models with zero field space curvature which can be reduced to free field theories by local, invertible field redefinitions. Here we study a model which cannot be so reduced and still shows the same sorts of large logarithms. We compute the evolution of the background at 1-loop and 2-loop orders, and we find the 1-loop $\beta$ and $\gamma$ functions. |
1708.01742 | Nan Li | Ze-Wei Zhao, Chun-Kai Yu, Nan Li | The black ring entropy from the Weyl tensor | 9 pages | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A black ring is an asymptotically flat vacuum solution of the Einstein
equations with an event horizon of topology $S^1\times S^2$. A connection
between the black ring entropy and its Weyl tensor $C_{\mu\nu\lambda\rho}$ is
explored by interpreting the Weyl scalar invariant $C_{\mu\nu\lambda\rho}
C^{\mu\nu\lambda\rho}$ as the entropy density in 5-dimensional space-time. We
calculate the proper volume integral of $C_{\mu\nu\lambda\rho}
C^{\mu\nu\lambda\rho}$ for a neutral black ring and prove that it is
proportional to the entropy of a thin black ring. Similar calculations are
extended to more general cases: the black string, the black ring with two
angular momenta, and the black ring with a cosmological constant. The
proportionality still maintains or is valid at least at the leading order.
| [
{
"created": "Sat, 5 Aug 2017 09:41:23 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Aug 2018 02:07:14 GMT",
"version": "v2"
}
] | 2018-08-08 | [
[
"Zhao",
"Ze-Wei",
""
],
[
"Yu",
"Chun-Kai",
""
],
[
"Li",
"Nan",
""
]
] | A black ring is an asymptotically flat vacuum solution of the Einstein equations with an event horizon of topology $S^1\times S^2$. A connection between the black ring entropy and its Weyl tensor $C_{\mu\nu\lambda\rho}$ is explored by interpreting the Weyl scalar invariant $C_{\mu\nu\lambda\rho} C^{\mu\nu\lambda\rho}$ as the entropy density in 5-dimensional space-time. We calculate the proper volume integral of $C_{\mu\nu\lambda\rho} C^{\mu\nu\lambda\rho}$ for a neutral black ring and prove that it is proportional to the entropy of a thin black ring. Similar calculations are extended to more general cases: the black string, the black ring with two angular momenta, and the black ring with a cosmological constant. The proportionality still maintains or is valid at least at the leading order. |
1803.00549 | Lukas Weih | Elias R. Most, Lukas R. Weih, Luciano Rezzolla, and J\"urgen
Schaffner-Bielich | New constraints on radii and tidal deformabilities of neutron stars from
GW170817 | Added discussion on EOSs with phase transitions; no changes for
purely hadronic EOSs; matches version accepted by PRL | Phys. Rev. Lett. 120, 261103 (2018) | 10.1103/PhysRevLett.120.261103 | null | gr-qc astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore in a parameterized manner a very large range of physically
plausible equations of state (EOSs) for compact stars for matter that is either
purely hadronic or that exhibits a phase transition. In particular, we produce
two classes of EOSs with and without phase transitions, each containing one
million EOSs. We then impose constraints on the maximum mass, ($M < 2.16
M_{\odot}$), and on the dimensionless tidal deformability ($\tilde{\Lambda}
<800$) deduced from GW170817, together with recent suggestions of lower limits
on $\tilde{\Lambda}$. Exploiting more than $10^9$ equilibrium models for each
class of EOSs, we produce distribution functions of all the stellar properties
and determine, among other quantities, the radius that is statistically most
probable for any value of the stellar mass. In this way, we deduce that the
radius of a purely hadronic neutron star with a representative mass of
$1.4\,M_{\odot}$ is constrained to be $12.00\!<\!R_{1.4}/{\rm km}\!<\!13.45$ at
a $2$-$\sigma$ confidence level, with a most likely value of
$\bar{R}_{1.4}=12.39\,{\rm km}$; similarly, the smallest dimensionless tidal
deformability is $\tilde{\Lambda}_{1.4}\!>\!375$, again at a $2$-$\sigma$
level. On the other hand, because EOSs with a phase transition allow for very
compact stars on the so-called `twin-star' branch, small radii are possible
with such EOSs although not probable, i.e. $8.53\!<\!R_{1.4}/{\rm
km}\!<\!13.74$ and $\bar{R}_{1.4}=13.06\,{\rm km}$ at a $2$-$\sigma$ level,
with $\tilde{\Lambda}_{1.4}\!>\!35.5$ at a $3$-$\sigma$ level. Finally, since
these EOSs exhibit upper limits on $\tilde{\Lambda}$, the detection of a binary
with total mass of $3.4\,M_{\odot}$ and $\tilde{\Lambda}_{1.7}\!>\!461$ can
rule out twin-star solutions.
| [
{
"created": "Thu, 1 Mar 2018 18:36:24 GMT",
"version": "v1"
},
{
"created": "Thu, 31 May 2018 11:15:49 GMT",
"version": "v2"
}
] | 2018-07-04 | [
[
"Most",
"Elias R.",
""
],
[
"Weih",
"Lukas R.",
""
],
[
"Rezzolla",
"Luciano",
""
],
[
"Schaffner-Bielich",
"Jürgen",
""
]
] | We explore in a parameterized manner a very large range of physically plausible equations of state (EOSs) for compact stars for matter that is either purely hadronic or that exhibits a phase transition. In particular, we produce two classes of EOSs with and without phase transitions, each containing one million EOSs. We then impose constraints on the maximum mass, ($M < 2.16 M_{\odot}$), and on the dimensionless tidal deformability ($\tilde{\Lambda} <800$) deduced from GW170817, together with recent suggestions of lower limits on $\tilde{\Lambda}$. Exploiting more than $10^9$ equilibrium models for each class of EOSs, we produce distribution functions of all the stellar properties and determine, among other quantities, the radius that is statistically most probable for any value of the stellar mass. In this way, we deduce that the radius of a purely hadronic neutron star with a representative mass of $1.4\,M_{\odot}$ is constrained to be $12.00\!<\!R_{1.4}/{\rm km}\!<\!13.45$ at a $2$-$\sigma$ confidence level, with a most likely value of $\bar{R}_{1.4}=12.39\,{\rm km}$; similarly, the smallest dimensionless tidal deformability is $\tilde{\Lambda}_{1.4}\!>\!375$, again at a $2$-$\sigma$ level. On the other hand, because EOSs with a phase transition allow for very compact stars on the so-called `twin-star' branch, small radii are possible with such EOSs although not probable, i.e. $8.53\!<\!R_{1.4}/{\rm km}\!<\!13.74$ and $\bar{R}_{1.4}=13.06\,{\rm km}$ at a $2$-$\sigma$ level, with $\tilde{\Lambda}_{1.4}\!>\!35.5$ at a $3$-$\sigma$ level. Finally, since these EOSs exhibit upper limits on $\tilde{\Lambda}$, the detection of a binary with total mass of $3.4\,M_{\odot}$ and $\tilde{\Lambda}_{1.7}\!>\!461$ can rule out twin-star solutions. |
1912.10210 | Kimihiro Nomura | Kimihiro Nomura, Asuka Ito, Jiro Soda | Pulsar timing residual induced by ultralight vector dark matter | 9 pages, 2 figures | Eur. Phys. J. C 80, 419 (2020) | 10.1140/epjc/s10052-020-7990-y | KOBE-COSMO-19-21 | gr-qc astro-ph.CO hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the ultralight vector dark matter with a mass around
$10^{-23}\,\mathrm{eV}$. The vector field oscillating coherently on galactic
scales induces oscillations of the spacetime metric with a frequency around
nHz, which is detectable by pulsar timing arrays. We find that the pulsar
timing signal due to the vector dark matter has nontrivial angular dependence
unlike the scalar dark matter and the maximal amplitude is three times larger
than that of the scalar dark matter.
| [
{
"created": "Sat, 21 Dec 2019 06:48:32 GMT",
"version": "v1"
},
{
"created": "Wed, 20 May 2020 11:53:03 GMT",
"version": "v2"
}
] | 2020-05-21 | [
[
"Nomura",
"Kimihiro",
""
],
[
"Ito",
"Asuka",
""
],
[
"Soda",
"Jiro",
""
]
] | We study the ultralight vector dark matter with a mass around $10^{-23}\,\mathrm{eV}$. The vector field oscillating coherently on galactic scales induces oscillations of the spacetime metric with a frequency around nHz, which is detectable by pulsar timing arrays. We find that the pulsar timing signal due to the vector dark matter has nontrivial angular dependence unlike the scalar dark matter and the maximal amplitude is three times larger than that of the scalar dark matter. |
1106.3666 | Kayll Lake | Kayll Lake and Majd Abdelqader | More on McVittie's Legacy: A Schwarzschild - de Sitter black and white
hole embedded in an asymptotically $\Lambda$CDM cosmology | 21 pages 17 figures revtex4-1 Final Form to appear in Phys. Rev. D | Phys.Rev.D84:044045,2011 | 10.1103/PhysRevD.84.044045 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently Kaloper, Kleban and Martin reexamined the McVittie solution and
argued, contrary to a very widely held belief, that the solution contains a
black hole in an expanding universe. Here we corroborate their main conclusion
but go on to examine, in some detail, a specific solution that asymptotes to
the $\Lambda$CDM cosmology. We show that part of the boundary of the solution
contains the inner bifurcation two - sphere of the Schwarzschild - de Sitter
spacetime and so both the black and white hole horizons together form a partial
boundary of this McVittie solution. We go on to show that the null and weak
energy conditions are satisfied and that the dominant energy condition is
satisfied almost everywhere in the solution. The solution is understood here by
way of a systematic construction of a conformal diagram based on detailed
numerical integrations of the null geodesic equations. We find that the
McVittie solution admits a degenerate limit in which the bifurcation two -
sphere disappears. For solutions with zero cosmological constant, we find no
evidence for the development of a weak null singularity. Rather, we find that
in this case there is either a black hole to the future of an initial
singularity or a white hole to its past.
| [
{
"created": "Sat, 18 Jun 2011 16:07:03 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jul 2011 18:25:56 GMT",
"version": "v2"
}
] | 2011-09-21 | [
[
"Lake",
"Kayll",
""
],
[
"Abdelqader",
"Majd",
""
]
] | Recently Kaloper, Kleban and Martin reexamined the McVittie solution and argued, contrary to a very widely held belief, that the solution contains a black hole in an expanding universe. Here we corroborate their main conclusion but go on to examine, in some detail, a specific solution that asymptotes to the $\Lambda$CDM cosmology. We show that part of the boundary of the solution contains the inner bifurcation two - sphere of the Schwarzschild - de Sitter spacetime and so both the black and white hole horizons together form a partial boundary of this McVittie solution. We go on to show that the null and weak energy conditions are satisfied and that the dominant energy condition is satisfied almost everywhere in the solution. The solution is understood here by way of a systematic construction of a conformal diagram based on detailed numerical integrations of the null geodesic equations. We find that the McVittie solution admits a degenerate limit in which the bifurcation two - sphere disappears. For solutions with zero cosmological constant, we find no evidence for the development of a weak null singularity. Rather, we find that in this case there is either a black hole to the future of an initial singularity or a white hole to its past. |
gr-qc/0112051 | Hossein Farajollahi | Hossein Farajollahi and Hugh Luckock | Dirac observables and the phase space of general relativity | Latex,18 pages,no figures | Gen.Rel.Grav. 34 (2002) 1685-1699 | null | null | gr-qc | null | In the canonical approach to general relativity it is customary to
parametrize the phase space by initial data on spacelike hypersurfaces.
However, if one seeks a theory dealing with observations that can be made by a
single localized observer, it is natural to use a different description of the
phase space. This results in a different set of Dirac observables from that
appearing in the conventional formulation. It also suggests a possible solution
to the problem of time, which has been one of the obstacles to the development
of a satisfactory quantum theory of gravity.
| [
{
"created": "Thu, 20 Dec 2001 06:10:37 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Dec 2001 01:49:16 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Farajollahi",
"Hossein",
""
],
[
"Luckock",
"Hugh",
""
]
] | In the canonical approach to general relativity it is customary to parametrize the phase space by initial data on spacelike hypersurfaces. However, if one seeks a theory dealing with observations that can be made by a single localized observer, it is natural to use a different description of the phase space. This results in a different set of Dirac observables from that appearing in the conventional formulation. It also suggests a possible solution to the problem of time, which has been one of the obstacles to the development of a satisfactory quantum theory of gravity. |
2203.08841 | Alejandro C\'ardenas-Avenda\~no | David Bronicki, Alejandro C\'ardenas-Avenda\~no, Leo C. Stein | Tidally-induced nonlinear resonances in EMRIs with an analogue model | V2. Updated to match published version | Class. Quantum Grav. 40 215015, 2023 | 10.1088/1361-6382/acfcfe | null | gr-qc astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | One of the important targets for the future space-based gravitational wave
observatory LISA is extreme mass ratio inspirals (EMRIs), where long and
accurate waveform modeling is necessary for detection and characterization.
Modeling EMRI dynamics requires accounting for effects such as the ones induced
by an external tidal field, which can break integrability at resonances and
cause significant dephasing. In this paper, we use a Newtonian analogue of a
Kerr black hole to study the effect of an external tidal field on the dynamics
and the gravitational waveform. We have developed a numerical framework that
takes advantage of the integrability of the background system to evolve it with
a symplectic splitting integrator, and compute approximate gravitational
waveforms to estimate the timescale over which the perturbation affects the
dynamics. Comparing this timescale with the characteristic time under radiation
reaction at resonance, we introduce a tool for quantifying the regime in which
tidal effects might be included when modeling EMRI gravitational waves. As an
application of this framework, we perform a detailed analysis of the dynamics
at one resonance to show how different entry points into the resonance in
phase-space can produce substantially different dynamics, and how one can
estimate bounds for the parameter space where tidal effects may become
dominant. Such bounds will scale as $\varepsilon \gtrsim C \, q$, where
$\varepsilon$ measures the strength of the external tidal field, $q$ is the
mass ratio, and $C$ is a number which depends on the resonance and the shape of
the tide. We demonstrate how to estimate $C$ using our framework for the 2:3
radial to polar frequency resonance in our model system. This framework can
serve as a proxy for proper modeling of the tidal perturbation in the fully
relativistic case.
| [
{
"created": "Wed, 16 Mar 2022 18:00:03 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Mar 2023 19:35:15 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Oct 2023 17:35:35 GMT",
"version": "v3"
}
] | 2023-10-11 | [
[
"Bronicki",
"David",
""
],
[
"Cárdenas-Avendaño",
"Alejandro",
""
],
[
"Stein",
"Leo C.",
""
]
] | One of the important targets for the future space-based gravitational wave observatory LISA is extreme mass ratio inspirals (EMRIs), where long and accurate waveform modeling is necessary for detection and characterization. Modeling EMRI dynamics requires accounting for effects such as the ones induced by an external tidal field, which can break integrability at resonances and cause significant dephasing. In this paper, we use a Newtonian analogue of a Kerr black hole to study the effect of an external tidal field on the dynamics and the gravitational waveform. We have developed a numerical framework that takes advantage of the integrability of the background system to evolve it with a symplectic splitting integrator, and compute approximate gravitational waveforms to estimate the timescale over which the perturbation affects the dynamics. Comparing this timescale with the characteristic time under radiation reaction at resonance, we introduce a tool for quantifying the regime in which tidal effects might be included when modeling EMRI gravitational waves. As an application of this framework, we perform a detailed analysis of the dynamics at one resonance to show how different entry points into the resonance in phase-space can produce substantially different dynamics, and how one can estimate bounds for the parameter space where tidal effects may become dominant. Such bounds will scale as $\varepsilon \gtrsim C \, q$, where $\varepsilon$ measures the strength of the external tidal field, $q$ is the mass ratio, and $C$ is a number which depends on the resonance and the shape of the tide. We demonstrate how to estimate $C$ using our framework for the 2:3 radial to polar frequency resonance in our model system. This framework can serve as a proxy for proper modeling of the tidal perturbation in the fully relativistic case. |
1812.03604 | Yun Soo Myung | Yun Soo Myung and De-Cheng Zou | Quasinormal modes of scalarized black holes in the
Einstein-Maxwell-Scalar theory | 19 pages, 12 figures, version to appear in PLB | null | 10.1016/j.physletb.2019.01.046 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform the stability analysis on scalarized charged black holes in the
Einstein-Maxwell-Scalar (EMS) theory by computing quasinormal mode spectrum. It
is noted that the appearance of these black holes with scalar hair is closely
related to the instability of Reissner-Nordstr\"om black holes without scalar
hair in the EMS theory. The scalarized black hole solutions are classified by
the node number of $n=0,1,2,\cdots$, where $n=0$ is called the fundamental
branch and $n=1,2,\cdots$ denote the $n$ excited branches. Here, we show that
the $n=1,2$ excited black holes are unstable against against the $s(l=0)$-mode
scalar perturbation, while the $n=0$ fundamental black hole is stable against
all scalar-vector-tensor perturbations. This is consistent with other
scalarized black holes without charge found in the Einstein-Scalar-Gauss-Bonnet
theory.
| [
{
"created": "Mon, 10 Dec 2018 03:09:19 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Jan 2019 22:59:49 GMT",
"version": "v2"
}
] | 2019-02-06 | [
[
"Myung",
"Yun Soo",
""
],
[
"Zou",
"De-Cheng",
""
]
] | We perform the stability analysis on scalarized charged black holes in the Einstein-Maxwell-Scalar (EMS) theory by computing quasinormal mode spectrum. It is noted that the appearance of these black holes with scalar hair is closely related to the instability of Reissner-Nordstr\"om black holes without scalar hair in the EMS theory. The scalarized black hole solutions are classified by the node number of $n=0,1,2,\cdots$, where $n=0$ is called the fundamental branch and $n=1,2,\cdots$ denote the $n$ excited branches. Here, we show that the $n=1,2$ excited black holes are unstable against against the $s(l=0)$-mode scalar perturbation, while the $n=0$ fundamental black hole is stable against all scalar-vector-tensor perturbations. This is consistent with other scalarized black holes without charge found in the Einstein-Scalar-Gauss-Bonnet theory. |
1407.3849 | Betti Hartmann | Eugenio R. Bezerra de Mello (UFPB, Brazil), Julio C. Fabris (UFES,
Brazil) and Betti Hartmann (UFES, Brazil & Jacobs University Bremen, Germany) | Abelian-Higgs strings in Rastall gravity | 12 pages including 4 figures; v2: statements clarified, typos
corrected; v3: matches version published in Class. Quantum Grav | Class. Quantum Grav. 32 (2015) 085009 | 10.1088/0264-9381/32/8/085009 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we analyze Abelian-Higgs strings in a phenomenological model
that takes quantum effects in curved space-time into account. This model, first
introduced by Rastall, cannot be derived from an action principle. We formulate
phenomenological equations of motion under the guiding principle of minimal
possible deformation of the standard equations. We construct string solutions
that asymptote to a flat space-time with a deficit angle by solving the set of
coupled non-linear ordinary differential equations numerically. Decreasing the
Rastall parameter from its Einstein gravity value we find that the deficit
angle of the space-time increases and becomes equal to $2\pi$ at some critical
value of this parameter that depends on the remaining couplings in the model.
For smaller values the resulting solutions are supermassive string solutions
possessing a singularity at a finite distance from the string core. Assuming
the Higgs boson mass to be on the order of the gauge boson mass we find that
also in Rastall gravity this happens only when the symmetry breaking scale is
on the order of the Planck mass. We also observe that for specific values of
the parameters in the model the energy per unit length becomes proportional to
the winding number, i.e. the degree of the map $S^1 \rightarrow S^1$. Unlike in
the BPS limit in Einstein gravity, this is, however, not connect to an
underlying mathematical structure, but rather constitutes a would-be-BPS bound.
| [
{
"created": "Mon, 14 Jul 2014 23:56:42 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Jul 2014 21:21:10 GMT",
"version": "v2"
},
{
"created": "Thu, 2 Apr 2015 01:45:16 GMT",
"version": "v3"
}
] | 2015-06-22 | [
[
"de Mello",
"Eugenio R. Bezerra",
"",
"UFPB, Brazil"
],
[
"Fabris",
"Julio C.",
"",
"UFES,\n Brazil"
],
[
"Hartmann",
"Betti",
"",
"UFES, Brazil & Jacobs University Bremen, Germany"
]
] | In this paper we analyze Abelian-Higgs strings in a phenomenological model that takes quantum effects in curved space-time into account. This model, first introduced by Rastall, cannot be derived from an action principle. We formulate phenomenological equations of motion under the guiding principle of minimal possible deformation of the standard equations. We construct string solutions that asymptote to a flat space-time with a deficit angle by solving the set of coupled non-linear ordinary differential equations numerically. Decreasing the Rastall parameter from its Einstein gravity value we find that the deficit angle of the space-time increases and becomes equal to $2\pi$ at some critical value of this parameter that depends on the remaining couplings in the model. For smaller values the resulting solutions are supermassive string solutions possessing a singularity at a finite distance from the string core. Assuming the Higgs boson mass to be on the order of the gauge boson mass we find that also in Rastall gravity this happens only when the symmetry breaking scale is on the order of the Planck mass. We also observe that for specific values of the parameters in the model the energy per unit length becomes proportional to the winding number, i.e. the degree of the map $S^1 \rightarrow S^1$. Unlike in the BPS limit in Einstein gravity, this is, however, not connect to an underlying mathematical structure, but rather constitutes a would-be-BPS bound. |
gr-qc/0409084 | Pavlin Savov | Pavlin Savov, Sergey Vyatchanin | Estimate of Tilt Instability of Mesa-Beam and Gaussian-Beam Modes for
Advanced LIGO | 10 pages, 3 figures, 4 tables | Phys.Rev. D74 (2006) 082002 | 10.1103/PhysRevD.74.082002 | null | gr-qc | null | Sidles and Sigg have shown that advanced LIGO interferometers will encounter
a serious tilt instability, in which symmetric tilts of the mirrors of an arm
cavity cause the cavity's light beam to slide sideways, so its radiation
pressure exerts a torque that increases the tilt. Sidles and Sigg showed that
the strength T of this torque is 26.2 times greater for advanced LIGO's
baseline cavities -- nearly flat spherical mirrors which support Gaussian beams
(``FG'' cavities), than for nearly concentric spherical mirrors which support
Gaussian beams with the same diffraction losses as the baseline case -- ``CG''
cavities: T^{FG}/T^{CG} = 26.2. This has motivated a proposal to change the
baseline design to nearly concentric, spherical mirrors. In order to reduce
thermoelastic noise in advanced LIGO, O'Shaughnessy and Thorne have proposed
replacing the spherical mirrors and their Gaussian beams by ``Mexican-Hat''
(MH) shaped mirrors which support flat-topped, ``mesa'' shaped beams. In this
paper we compute the tilt-instability torque for advanced-LIGO cavities with
nearly flat MH mirrors and mesa beams (``FM'' cavities) and nearly concentric
MH mirrors and mesa beams (``CM'' cavities), with the same diffraction losses
as in the baseline FG case. We find that the relative sizes of the restoring
torques are T^{CM}/T^{CG} = 0.91, T^{FM}/T^{CG} = 96, T^{FM}/T^{FG} = 3.67.
Thus, the nearly concentric MH mirrors have a weaker tilt instability than any
other configuration. Their thermoelastic noise is the same as for nearly flat
MH mirrors, and is much lower than for spherical mirrors.
| [
{
"created": "Tue, 21 Sep 2004 23:08:47 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Savov",
"Pavlin",
""
],
[
"Vyatchanin",
"Sergey",
""
]
] | Sidles and Sigg have shown that advanced LIGO interferometers will encounter a serious tilt instability, in which symmetric tilts of the mirrors of an arm cavity cause the cavity's light beam to slide sideways, so its radiation pressure exerts a torque that increases the tilt. Sidles and Sigg showed that the strength T of this torque is 26.2 times greater for advanced LIGO's baseline cavities -- nearly flat spherical mirrors which support Gaussian beams (``FG'' cavities), than for nearly concentric spherical mirrors which support Gaussian beams with the same diffraction losses as the baseline case -- ``CG'' cavities: T^{FG}/T^{CG} = 26.2. This has motivated a proposal to change the baseline design to nearly concentric, spherical mirrors. In order to reduce thermoelastic noise in advanced LIGO, O'Shaughnessy and Thorne have proposed replacing the spherical mirrors and their Gaussian beams by ``Mexican-Hat'' (MH) shaped mirrors which support flat-topped, ``mesa'' shaped beams. In this paper we compute the tilt-instability torque for advanced-LIGO cavities with nearly flat MH mirrors and mesa beams (``FM'' cavities) and nearly concentric MH mirrors and mesa beams (``CM'' cavities), with the same diffraction losses as in the baseline FG case. We find that the relative sizes of the restoring torques are T^{CM}/T^{CG} = 0.91, T^{FM}/T^{CG} = 96, T^{FM}/T^{FG} = 3.67. Thus, the nearly concentric MH mirrors have a weaker tilt instability than any other configuration. Their thermoelastic noise is the same as for nearly flat MH mirrors, and is much lower than for spherical mirrors. |
2109.12037 | Elena Medina | Gabriel \'Alvarez, Luis Mart\'inez Alonso, Elena Medina | Kinetic dominance and the wavefunction of the universe | 26 pages, 6 figures | null | 10.1103/PhysRevD.105.083502 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | We analyze the emergence of classical inflationary universes in a
kinetic-dominated stage using a suitable class of solutions of the Wheeler-De
Witt equation with a constant potential. These solutions are eigenfunctions of
the inflaton momentum operator that are strongly peaked on classical solutions
exhibiting either or both a kinetic dominated period and an inflation period.
Our analysis is based on semiclassical WKB solutions of the Wheeler-De Witt
equation interpreted in the sense of Borel (to perform a correct connection
between classically allowed regions) and on the relationship of these solutions
to the solutions of the classical model. For large values of the scale factor
the WKB Vilenkin tunneling wavefunction and the Hartle-Hawking no-boundary
wavefunctions are recovered as particular instances of our class of
wavefunctions.
| [
{
"created": "Fri, 24 Sep 2021 15:50:34 GMT",
"version": "v1"
}
] | 2022-04-20 | [
[
"Álvarez",
"Gabriel",
""
],
[
"Alonso",
"Luis Martínez",
""
],
[
"Medina",
"Elena",
""
]
] | We analyze the emergence of classical inflationary universes in a kinetic-dominated stage using a suitable class of solutions of the Wheeler-De Witt equation with a constant potential. These solutions are eigenfunctions of the inflaton momentum operator that are strongly peaked on classical solutions exhibiting either or both a kinetic dominated period and an inflation period. Our analysis is based on semiclassical WKB solutions of the Wheeler-De Witt equation interpreted in the sense of Borel (to perform a correct connection between classically allowed regions) and on the relationship of these solutions to the solutions of the classical model. For large values of the scale factor the WKB Vilenkin tunneling wavefunction and the Hartle-Hawking no-boundary wavefunctions are recovered as particular instances of our class of wavefunctions. |
gr-qc/0212054 | Annelies Gerber | P Dolan and A Gerber | The Riemann-Lanczos Problem as an Exterior Differential System with
Examples in 4 and 5 Dimensions | 26 pages, latex, no figures | null | null | null | gr-qc | null | The key problem of the theory of exterior differential systems (EDS) is to
decide whether or not a system is in involution. The special case of EDSs
generated by one-forms (Pfaffian systems) can be adequately illustrated by a
2-dimensional example. In 4 dimensions two such problems arise in a natural
way, namely, the Riemann-Lanczos and the Weyl-Lanczos problems. It is known
from the work of Bampi and Caviglia that the Weyl-Lanczos problem is always in
involution in both 4 and 5 dimensions but that the Riemann-Lanczos problem
fails to be in involution even for 4 dimensions. However, singular solutions of
it can be found. We give examples of singular solutions for the Goedel, Kasner
and Debever-Hubaut spacetimes. It is even possible that the singular solution
can inherit the spacetime symmetries as in the Debever-Hubaut case. We comment
on the Riemann-Lanczos problem in 5 dimensions which is neither in involution
nor does it admit a 5-dimensional involution of Vessiot vector fields in the
generic case.
| [
{
"created": "Thu, 12 Dec 2002 10:13:54 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dolan",
"P",
""
],
[
"Gerber",
"A",
""
]
] | The key problem of the theory of exterior differential systems (EDS) is to decide whether or not a system is in involution. The special case of EDSs generated by one-forms (Pfaffian systems) can be adequately illustrated by a 2-dimensional example. In 4 dimensions two such problems arise in a natural way, namely, the Riemann-Lanczos and the Weyl-Lanczos problems. It is known from the work of Bampi and Caviglia that the Weyl-Lanczos problem is always in involution in both 4 and 5 dimensions but that the Riemann-Lanczos problem fails to be in involution even for 4 dimensions. However, singular solutions of it can be found. We give examples of singular solutions for the Goedel, Kasner and Debever-Hubaut spacetimes. It is even possible that the singular solution can inherit the spacetime symmetries as in the Debever-Hubaut case. We comment on the Riemann-Lanczos problem in 5 dimensions which is neither in involution nor does it admit a 5-dimensional involution of Vessiot vector fields in the generic case. |
0808.1295 | Merab Gogberashvili Dr | Merab Gogberashvili and Ramaz Khomeriki | Trapping of Nonlinear Gravitational Waves by Two-Fluid Systems | 8 pages, the version accepted by Mod. Phys. Lett. A | Mod.Phys.Lett.A24:2761-2768,2009 | 10.1142/S0217732309032083 | null | gr-qc astro-ph hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that the coupled two-fluid gravitating system (e.g. stiff matter and
'vacuum energy') could trap nonlinear gravitational waves (e.g. Einstein-Rosen
waves). The gravitational wave amplitude varies harmonically in time
transferring the energy coherently to the stiff matter wave, and then the
process goes to the backward direction. This process mimics the behaviour of
trapped electromagnetic waves in two-level media. We have defined the limits
for the frequency of this energy transfer oscillations.
| [
{
"created": "Fri, 8 Aug 2008 20:55:44 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Sep 2009 09:07:27 GMT",
"version": "v2"
}
] | 2009-12-08 | [
[
"Gogberashvili",
"Merab",
""
],
[
"Khomeriki",
"Ramaz",
""
]
] | We show that the coupled two-fluid gravitating system (e.g. stiff matter and 'vacuum energy') could trap nonlinear gravitational waves (e.g. Einstein-Rosen waves). The gravitational wave amplitude varies harmonically in time transferring the energy coherently to the stiff matter wave, and then the process goes to the backward direction. This process mimics the behaviour of trapped electromagnetic waves in two-level media. We have defined the limits for the frequency of this energy transfer oscillations. |
0906.1949 | Kostyantyn Ropotenko | Kostyantyn Ropotenko | Quantization of the black hole area as quantization of the angular
momentum component | 4 pages (revtex), no figures; a boundary condition for the
differential equation (15) added; the absent of the remnants in the approach
noted; a reference added; accepted by Physical Review D for publication | Phys.Rev.D80:044022,2009 | 10.1103/PhysRevD.80.044022 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In transforming from Schwarzschild to Euclidean Rindler coordinates the
Schwarzschild time transforms to a periodic angle. As is well-known, this
allows one to introduce the Hawking temperature and is an origin of black hole
thermodynamics. On the other hand, according to quantum mechanics this angle is
conjugate to the $z$ component of the angular momentum. From the commutation
relation and quantization condition for the angular momentum component it is
found that the area of the horizon of a Schwarzschild black hole is quantized
with the quantum $\Delta A = 8\pi l_P^{2}$. It is shown that this conclusion is
also valid for a generic Kerr-Newman black hole.
| [
{
"created": "Wed, 10 Jun 2009 15:46:56 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Jun 2009 14:36:20 GMT",
"version": "v2"
},
{
"created": "Thu, 13 Aug 2009 12:54:42 GMT",
"version": "v3"
}
] | 2009-09-01 | [
[
"Ropotenko",
"Kostyantyn",
""
]
] | In transforming from Schwarzschild to Euclidean Rindler coordinates the Schwarzschild time transforms to a periodic angle. As is well-known, this allows one to introduce the Hawking temperature and is an origin of black hole thermodynamics. On the other hand, according to quantum mechanics this angle is conjugate to the $z$ component of the angular momentum. From the commutation relation and quantization condition for the angular momentum component it is found that the area of the horizon of a Schwarzschild black hole is quantized with the quantum $\Delta A = 8\pi l_P^{2}$. It is shown that this conclusion is also valid for a generic Kerr-Newman black hole. |
2311.04972 | Alex Va\~n\'o-Vi\~nuales | Alex Va\~n\'o-Vi\~nuales | Conformal diagrams for stationary and dynamical strong-field
hyperboloidal slices | 18 pages, 14 figures, matches published version | Classical and Quantum Gravity 41 (2024) 105003 | 10.1088/1361-6382/ad3aca | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Conformal Carter-Penrose diagrams are used for the visualization of
hyperboloidal slices, which are smooth spacelike slices reaching null infinity.
The focus is on the Schwarzschild black hole geometry in spherical symmetry,
whose Penrose diagrams are introduced in a pedagogical way. The stationary
regime involves time-independent slices. In this case, different options are
given for integrating the height function -- the main ingredient for
constructing hyperboloidal foliations. The dynamical regime considers slices
changing in time, which are evolved together with the spacetime using the
eikonal equation. It includes the relaxation of hyperboloidal Schwarzschild
trumpet slices and the collapse of a massless scalar field into a black hole,
for which Penrose diagrams are presented.
| [
{
"created": "Wed, 8 Nov 2023 19:00:03 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Apr 2024 11:49:27 GMT",
"version": "v2"
}
] | 2024-04-24 | [
[
"Vañó-Viñuales",
"Alex",
""
]
] | Conformal Carter-Penrose diagrams are used for the visualization of hyperboloidal slices, which are smooth spacelike slices reaching null infinity. The focus is on the Schwarzschild black hole geometry in spherical symmetry, whose Penrose diagrams are introduced in a pedagogical way. The stationary regime involves time-independent slices. In this case, different options are given for integrating the height function -- the main ingredient for constructing hyperboloidal foliations. The dynamical regime considers slices changing in time, which are evolved together with the spacetime using the eikonal equation. It includes the relaxation of hyperboloidal Schwarzschild trumpet slices and the collapse of a massless scalar field into a black hole, for which Penrose diagrams are presented. |
2101.02019 | Ion I. Cotaescu | Ion I. Cotaescu | Light from Reissner-Nordstrom-de Sitter black holes | 14 pages, 3 figures. arXiv admin note: text overlap with
arXiv:2011.02434 | null | 10.1142/S0217732321501625 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive for the first time the form of the spiral null geodesics around the
photon sphere of the Reissner-Nordstrom black hole in the de Sitter expanding
universe. Moreover, we obtain the principal parameter we need for deriving,
according to our method [I. I. Cot\u aescu. {Eur. Phys. J. C.} (2021) 81:32],
the black hole shadow and the related redshift as measured by a remote observer
situated in the asymptotic zone. We obtain thus a criterion of detecting
charged black holes without peculiar velocities when one knows the mass,
redshift and the black hole shadow.
| [
{
"created": "Wed, 6 Jan 2021 13:36:35 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Jan 2021 13:25:50 GMT",
"version": "v2"
},
{
"created": "Thu, 22 Apr 2021 19:09:08 GMT",
"version": "v3"
}
] | 2021-08-11 | [
[
"Cotaescu",
"Ion I.",
""
]
] | We derive for the first time the form of the spiral null geodesics around the photon sphere of the Reissner-Nordstrom black hole in the de Sitter expanding universe. Moreover, we obtain the principal parameter we need for deriving, according to our method [I. I. Cot\u aescu. {Eur. Phys. J. C.} (2021) 81:32], the black hole shadow and the related redshift as measured by a remote observer situated in the asymptotic zone. We obtain thus a criterion of detecting charged black holes without peculiar velocities when one knows the mass, redshift and the black hole shadow. |
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