id
stringlengths
9
13
submitter
stringlengths
1
64
authors
stringlengths
5
22.9k
title
stringlengths
4
245
comments
stringlengths
1
548
journal-ref
stringlengths
4
362
doi
stringlengths
12
82
report-no
stringlengths
2
281
categories
stringclasses
793 values
license
stringclasses
9 values
orig_abstract
stringlengths
24
1.95k
versions
listlengths
1
30
update_date
stringlengths
10
10
authors_parsed
listlengths
1
1.74k
abstract
stringlengths
21
1.95k
gr-qc/9404007
null
David Brown
Reference Fluids as Standards of Space and Time
(plain TeX, 3 pages)
null
null
null
gr-qc hep-th
null
The idea that spacetime points are to be identified by a fleet of clock--carrying particles can be traced to the earliest days of general relativity. Such a fleet of clocks can be described phenomenologically as a reference fluid. One approach to the problem of time consists in coupling the metric to a reference flui...
[ { "created": "Wed, 6 Apr 1994 15:53:14 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brown", "David", "" ] ]
The idea that spacetime points are to be identified by a fleet of clock--carrying particles can be traced to the earliest days of general relativity. Such a fleet of clocks can be described phenomenologically as a reference fluid. One approach to the problem of time consists in coupling the metric to a reference fluid ...
1211.1855
Mayeul Arminjon
Mayeul Arminjon
Should there be a spin-rotation coupling for a Dirac particle?
29 pages in standard 12pt. V2: Introduction reinforced. New Section 3 on the dependences of the Hamiltonian on the reference frame and on the tetrad field. New references
Int. J. Theor. Phys., Vol. 53, No. 6, pp. 1993-2013 (2014)
10.1007/s10773-014-2006-z
null
gr-qc quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It was argued by Mashhoon that a spin-rotation coupling term should add to the Hamiltonian operator in a rotating frame, as compared with the one in an inertial frame. For a Dirac particle, the Hamiltonian and energy operators H and E were recently proved to depend on the tetrad field. We argue that this non-uniquene...
[ { "created": "Thu, 8 Nov 2012 14:08:09 GMT", "version": "v1" }, { "created": "Mon, 9 Sep 2013 14:03:19 GMT", "version": "v2" } ]
2014-05-16
[ [ "Arminjon", "Mayeul", "" ] ]
It was argued by Mashhoon that a spin-rotation coupling term should add to the Hamiltonian operator in a rotating frame, as compared with the one in an inertial frame. For a Dirac particle, the Hamiltonian and energy operators H and E were recently proved to depend on the tetrad field. We argue that this non-uniqueness...
2107.03258
Bei Sha
Bei Sha and Zhi-E Liu
Lorentz-breaking Theory and Tunneling Radiation Correction to Vaidya-Banner de Sitter Black Hole
13 pages,0 figure
null
null
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In Vaidya-Bonner de Sitter Black hole space-time, the tunneling radiation characteristics of fermions and bosons are corrected by taking Lorentz symmetry breaking theory into account. The corresponding gamma matrices and ether-like field vectors of the black hole are constructed, then the new modified form of Dirac e...
[ { "created": "Wed, 7 Jul 2021 14:45:20 GMT", "version": "v1" } ]
2021-07-08
[ [ "Sha", "Bei", "" ], [ "Liu", "Zhi-E", "" ] ]
In Vaidya-Bonner de Sitter Black hole space-time, the tunneling radiation characteristics of fermions and bosons are corrected by taking Lorentz symmetry breaking theory into account. The corresponding gamma matrices and ether-like field vectors of the black hole are constructed, then the new modified form of Dirac equ...
2312.11358
Harry Ho-Yin Ng
Harry Ho-Yin Ng, Jin-Liang Jiang, Carlo Musolino, Christian Ecker, Samuel D.Tootle, Luciano Rezzolla
A hybrid approach to long-term binary neutron-star simulations
25 pages, 13 figures
Phys. Rev. D (2024) 109, 064061
10.1103/PhysRevD.109.064061
null
gr-qc
http://creativecommons.org/licenses/by-nc-sa/4.0/
One of the main challenges in the numerical modeling of binary neutron-star (BNS) mergers is long-term simulations of the post-merger remnant over timescales of the order of seconds. When this modeling includes all the aspects of complex physics, the computational costs can easily become enormous. To address this cha...
[ { "created": "Mon, 18 Dec 2023 17:15:33 GMT", "version": "v1" }, { "created": "Fri, 22 Dec 2023 19:43:37 GMT", "version": "v2" }, { "created": "Tue, 9 Apr 2024 13:08:35 GMT", "version": "v3" } ]
2024-04-11
[ [ "Ng", "Harry Ho-Yin", "" ], [ "Jiang", "Jin-Liang", "" ], [ "Musolino", "Carlo", "" ], [ "Ecker", "Christian", "" ], [ "Tootle", "Samuel D.", "" ], [ "Rezzolla", "Luciano", "" ] ]
One of the main challenges in the numerical modeling of binary neutron-star (BNS) mergers is long-term simulations of the post-merger remnant over timescales of the order of seconds. When this modeling includes all the aspects of complex physics, the computational costs can easily become enormous. To address this chall...
1801.01420
Paolo Pani
Vitor Cardoso, \'Oscar J. C. Dias, Gavin S. Hartnett, Matthew Middleton, Paolo Pani, Jorge E. Santos
Constraining the mass of dark photons and axion-like particles through black-hole superradiance
24 pages, 12 pages. Includes supplemental datafile
null
10.1088/1475-7516/2018/03/043
null
gr-qc astro-ph.HE hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Ultralight bosons and axion-like particles appear naturally in different scenarios and could solve some long-standing puzzles. Their detection is challenging, and all direct methods hinge on unknown couplings to the Standard Model of particle physics. However, the universal coupling to gravity provides model-independ...
[ { "created": "Thu, 4 Jan 2018 16:12:50 GMT", "version": "v1" } ]
2018-04-11
[ [ "Cardoso", "Vitor", "" ], [ "Dias", "Óscar J. C.", "" ], [ "Hartnett", "Gavin S.", "" ], [ "Middleton", "Matthew", "" ], [ "Pani", "Paolo", "" ], [ "Santos", "Jorge E.", "" ] ]
Ultralight bosons and axion-like particles appear naturally in different scenarios and could solve some long-standing puzzles. Their detection is challenging, and all direct methods hinge on unknown couplings to the Standard Model of particle physics. However, the universal coupling to gravity provides model-independen...
1301.3508
Ahmed Farag Ali
Ahmed Farag Ali (Benha U.) and A. Tawfik (Egyptian Ctr. Theor. Phys., Cairo and Freie U., Berlin)
Modified Newton's Law of Gravitation Due to Minimal Length in Quantum Gravity
12 pages, no figures, references added
Adv.High Energy Phys. 2013 (2013) 126528
10.1155/2013/126528
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recent theory about the origin of the gravity suggests that the gravity is originally an entropic force. In this work, we discuss the effects of generalized uncertainty principle (GUP) which is proposed by some approaches to quantum gravity such as string theory, black hole physics and doubly special relativity the...
[ { "created": "Tue, 15 Jan 2013 21:50:54 GMT", "version": "v1" }, { "created": "Fri, 22 Feb 2013 14:41:27 GMT", "version": "v2" } ]
2013-02-25
[ [ "Ali", "Ahmed Farag", "", "Benha U." ], [ "Tawfik", "A.", "", "Egyptian Ctr. Theor. Phys.,\n Cairo and Freie U., Berlin" ] ]
A recent theory about the origin of the gravity suggests that the gravity is originally an entropic force. In this work, we discuss the effects of generalized uncertainty principle (GUP) which is proposed by some approaches to quantum gravity such as string theory, black hole physics and doubly special relativity theor...
gr-qc/0009055
Kazuhiro Tominaga
Kazuhiro Tominaga, Motoyuki Saijo, and Kei-ichi Maeda
Gravitational waves from a spinning particle scattered by a relativistic star: Axial mode case
REVTeX, 17 pages with 13 figures. Submitted to Phys. Rev. D
Phys.Rev.D63:124012,2001
10.1103/PhysRevD.63.124012
WU-AP/112/00 (Waseda Univ. Astrophysics)
gr-qc
null
We study gravitational waves from a spinning test particle scattered by a relativistic star using a perturbation method. The present analysis is restricted to axial modes. By calculating the energy spectrum, the waveforms and the total energy and angular momentum of gravitational waves, we analyze the dependence of t...
[ { "created": "Fri, 15 Sep 2000 15:31:35 GMT", "version": "v1" } ]
2014-11-17
[ [ "Tominaga", "Kazuhiro", "" ], [ "Saijo", "Motoyuki", "" ], [ "Maeda", "Kei-ichi", "" ] ]
We study gravitational waves from a spinning test particle scattered by a relativistic star using a perturbation method. The present analysis is restricted to axial modes. By calculating the energy spectrum, the waveforms and the total energy and angular momentum of gravitational waves, we analyze the dependence of the...
gr-qc/9701038
Paul Parsons
John D. Barrow (University of Sussex)
Cosmological Limits on Slightly Skew Stresses
Latex, requires sw20lart package. No figures
Phys.Rev. D55 (1997) 7451-7460
10.1103/PhysRevD.55.7451
null
gr-qc astro-ph
null
We present an analysis of the cosmological evolution of matter sources with small anisotropic pressures. This includes electric and magnetic fields, collisionless relativistic particles, gravitons, antisymmetric axion fields in low-energy string cosmologies, spatial curvature anisotropies, and stresses arising from s...
[ { "created": "Thu, 16 Jan 1997 15:14:15 GMT", "version": "v1" } ]
2009-10-30
[ [ "Barrow", "John D.", "", "University of Sussex" ] ]
We present an analysis of the cosmological evolution of matter sources with small anisotropic pressures. This includes electric and magnetic fields, collisionless relativistic particles, gravitons, antisymmetric axion fields in low-energy string cosmologies, spatial curvature anisotropies, and stresses arising from sim...
1804.10551
Yusuf Sucu
Ganim Gecim and Yusuf Sucu
Quantum gravity effect on the Hawking radiation of charged rotating BTZ black hole
Published version in General Relativity and Gravitation
Gen Relativ Gravit (2018) 50: 152
10.1007/s10714-018-2478-x
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this study, the quantum gravity effect on the tunnelling radiation of charged massive spin-0 scalar particle from 2+1 dimensional charged rotating Banados-Teitelboim-Zanelli (BTZ) black hole is looked into by using the Hamilton-Jacobi approach. For this, we calculate the modified Hawking temperature of the black h...
[ { "created": "Fri, 27 Apr 2018 15:12:55 GMT", "version": "v1" }, { "created": "Sun, 10 Jun 2018 14:38:40 GMT", "version": "v2" }, { "created": "Mon, 12 Nov 2018 10:02:02 GMT", "version": "v3" } ]
2018-11-13
[ [ "Gecim", "Ganim", "" ], [ "Sucu", "Yusuf", "" ] ]
In this study, the quantum gravity effect on the tunnelling radiation of charged massive spin-0 scalar particle from 2+1 dimensional charged rotating Banados-Teitelboim-Zanelli (BTZ) black hole is looked into by using the Hamilton-Jacobi approach. For this, we calculate the modified Hawking temperature of the black hol...
1212.6654
Sunil Maharaj
M. C. Kweyama, K. S. Govinder, S. D. Maharaj
Noether and Lie symmetries for charged perfect fluids
17 pages, To appear in Class. Quantum Grav
Class. Quantum Grav. 28: 105005, 2011
10.1088/0264-9381/28/10/105005
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the underlying nonlinear partial differential equation that governs the behaviour of spherically symmetric charged fluids in general relativity. We investigate the conditions for the equation to admit a first integral or be reduced to quadratures using symmetry methods for differential equations. A general N...
[ { "created": "Sat, 29 Dec 2012 18:43:13 GMT", "version": "v1" } ]
2015-06-12
[ [ "Kweyama", "M. C.", "" ], [ "Govinder", "K. S.", "" ], [ "Maharaj", "S. D.", "" ] ]
We study the underlying nonlinear partial differential equation that governs the behaviour of spherically symmetric charged fluids in general relativity. We investigate the conditions for the equation to admit a first integral or be reduced to quadratures using symmetry methods for differential equations. A general Noe...
1409.6839
Behrouz Mirza
Behrouz Mirza, Zeinab Sherkatghanad
Phase transitions of hairy black holes in massive gravity and thermodynamic behavior of charged AdS black holes in an extended phase space
7 pages, 6 figures
Phys. Rev. D 90, 084006 (2014)
10.1103/PhysRevD.90.084006
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the thermodynamic behavior of static and spherically symmetric hairy black holes in massive gravity. In this case, the black hole is surrounded in a spherical cavity with a fixed temperature on the surface. It is observed that these black holes have a phase transition similar to the liquid-gas phase transiti...
[ { "created": "Wed, 24 Sep 2014 06:20:01 GMT", "version": "v1" }, { "created": "Wed, 8 Oct 2014 21:49:36 GMT", "version": "v2" } ]
2015-06-23
[ [ "Mirza", "Behrouz", "" ], [ "Sherkatghanad", "Zeinab", "" ] ]
We study the thermodynamic behavior of static and spherically symmetric hairy black holes in massive gravity. In this case, the black hole is surrounded in a spherical cavity with a fixed temperature on the surface. It is observed that these black holes have a phase transition similar to the liquid-gas phase transition...
1605.04860
Sharmanthie Fernando
Sharmanthie Fernando
Phase transitions of black holes in massive gravity
Accepted to be published in Modern Physics Letters A. Three more references added
Modern Physics Lettets A, Vol.31, No. 16, 1650096 (2016)
10.1142/S0217732316500966
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we have studied thermodynamics of a black hole in massive gravity in the canonical ensemble. The massive gravity theory in consideration here has a massive graviton due to Lorentz symmetry breaking. The black hole studied here has a scalar charge due to the massive graviton and is asymptotically anti-de...
[ { "created": "Mon, 16 May 2016 18:14:25 GMT", "version": "v1" }, { "created": "Thu, 19 May 2016 18:02:48 GMT", "version": "v2" }, { "created": "Wed, 14 Dec 2016 15:10:44 GMT", "version": "v3" } ]
2016-12-15
[ [ "Fernando", "Sharmanthie", "" ] ]
In this paper we have studied thermodynamics of a black hole in massive gravity in the canonical ensemble. The massive gravity theory in consideration here has a massive graviton due to Lorentz symmetry breaking. The black hole studied here has a scalar charge due to the massive graviton and is asymptotically anti-de S...
1405.5074
Elena P. Savelova Dr.
A.A. Kirillov, E.P. Savelova
Effective action for a free scalar field in the presence of spacetime foam
null
GRG 47, 97 (2015)
10.1007/s10714-015-1941-1
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We model spacetime foam by a gas of virtual wormholes. For a free scalar field we derive the effective Lagrangian which accounts for the interaction with spacetime foam and contains two additional non-local terms. One term describes the scattering of scalar particles on virtual wormholes and explicitly reproduces the...
[ { "created": "Tue, 20 May 2014 13:13:09 GMT", "version": "v1" }, { "created": "Sun, 8 Jun 2014 16:53:20 GMT", "version": "v2" }, { "created": "Sat, 21 Jun 2014 17:25:00 GMT", "version": "v3" }, { "created": "Sun, 9 Aug 2015 05:45:02 GMT", "version": "v4" } ]
2015-08-11
[ [ "Kirillov", "A. A.", "" ], [ "Savelova", "E. P.", "" ] ]
We model spacetime foam by a gas of virtual wormholes. For a free scalar field we derive the effective Lagrangian which accounts for the interaction with spacetime foam and contains two additional non-local terms. One term describes the scattering of scalar particles on virtual wormholes and explicitly reproduces the P...
gr-qc/0611112
Martin Bojowald
Martin Bojowald, Hector Hernandez, Mikhail Kagan and Aureliano Skirzewski
Effective constraints of loop quantum gravity
44 pages, 6 figures
Phys.Rev.D75:064022,2007
10.1103/PhysRevD.75.064022
IGPG-06/11-4, AEI-2006-086
gr-qc astro-ph hep-th
null
Within a perturbative cosmological regime of loop quantum gravity corrections to effective constraints are computed. This takes into account all inhomogeneous degrees of freedom relevant for scalar metric modes around flat space and results in explicit expressions for modified coefficients and of higher order terms. ...
[ { "created": "Tue, 21 Nov 2006 20:37:26 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bojowald", "Martin", "" ], [ "Hernandez", "Hector", "" ], [ "Kagan", "Mikhail", "" ], [ "Skirzewski", "Aureliano", "" ] ]
Within a perturbative cosmological regime of loop quantum gravity corrections to effective constraints are computed. This takes into account all inhomogeneous degrees of freedom relevant for scalar metric modes around flat space and results in explicit expressions for modified coefficients and of higher order terms. It...
gr-qc/0307099
Ozgur Delice
Ozgur Delice
Gravitational hedgehog, stringy hedgehog and stringy sphere
11 pages
JHEP 0311 (2003) 058
10.1088/1126-6708/2003/11/058
null
gr-qc
null
We investigate the solutions of Einstein equations such that a hedgehog solution is matched to different exterior or interior solutions via a spherical shell. In the case where both the exterior and the interior regions are hedgehog solutions or one of them is flat, the resulting spherical shell becomes a stringy she...
[ { "created": "Wed, 23 Jul 2003 11:53:52 GMT", "version": "v1" }, { "created": "Tue, 21 Oct 2003 17:39:44 GMT", "version": "v2" }, { "created": "Wed, 3 Dec 2003 14:09:14 GMT", "version": "v3" } ]
2007-05-23
[ [ "Delice", "Ozgur", "" ] ]
We investigate the solutions of Einstein equations such that a hedgehog solution is matched to different exterior or interior solutions via a spherical shell. In the case where both the exterior and the interior regions are hedgehog solutions or one of them is flat, the resulting spherical shell becomes a stringy shell...
1608.00002
Juan Antonio Nieto
J. A. Nieto
Alternative Self-dual Gravity in Eight Dimensions
12 pages, Latex, accepted for publication in Modern Physics Letters A
null
10.1142/S0217732316501479
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop an alternative Ashtekar formalism in eight dimensions. In fact, using a MacDowell-Mansouri physical framework and a self-dual curvature symmetry we propose an action in eight dimensions in which the Levi-Civita tenor with eight indices plays a key role. We explicitly show that such an action contains numbe...
[ { "created": "Fri, 29 Jul 2016 16:47:04 GMT", "version": "v1" } ]
2016-09-07
[ [ "Nieto", "J. A.", "" ] ]
We develop an alternative Ashtekar formalism in eight dimensions. In fact, using a MacDowell-Mansouri physical framework and a self-dual curvature symmetry we propose an action in eight dimensions in which the Levi-Civita tenor with eight indices plays a key role. We explicitly show that such an action contains number ...
1201.2814
Paolo Pani
Paolo Pani, Terence Delsate, Vitor Cardoso
Eddington-inspired Born-Infeld gravity. Phenomenology of non-linear gravity-matter coupling
16 pages, 13 figures. v2: improved section on the linear structure of the theory, one reference added. Version accepted in PRD
null
10.1103/PhysRevD.85.084020
null
gr-qc astro-ph.SR hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Viable corrections to the matter sector of Poisson's equation may result in qualitatively different astrophysical phenomenology, for example the gravitational collapse and the properties of compact objects can change drastically. We discuss a class of modified non-relativistic theories and focus on a relativistic com...
[ { "created": "Fri, 13 Jan 2012 12:08:02 GMT", "version": "v1" }, { "created": "Fri, 2 Mar 2012 18:00:06 GMT", "version": "v2" } ]
2013-05-30
[ [ "Pani", "Paolo", "" ], [ "Delsate", "Terence", "" ], [ "Cardoso", "Vitor", "" ] ]
Viable corrections to the matter sector of Poisson's equation may result in qualitatively different astrophysical phenomenology, for example the gravitational collapse and the properties of compact objects can change drastically. We discuss a class of modified non-relativistic theories and focus on a relativistic compl...
2401.15965
Qingyu Gan
Andrea Addazi, Salvatore Capozziello, Qingyu Gan
Resonant Graviton-Photon Conversion with Stochastic Magnetic Field in the Expanding Universe
29 pages, 5 figures
null
null
null
gr-qc astro-ph.CO hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate graviton-photon oscillations sourced by cosmological magnetic fields from Gertsenshtein effect. We adopt a robust perturbative approach and we find that the conversion probability from graviton to photon can be resonantly enhanced in monochromatic, multi-chromatic and scale invariant spectrum models of...
[ { "created": "Mon, 29 Jan 2024 08:52:32 GMT", "version": "v1" } ]
2024-01-30
[ [ "Addazi", "Andrea", "" ], [ "Capozziello", "Salvatore", "" ], [ "Gan", "Qingyu", "" ] ]
We investigate graviton-photon oscillations sourced by cosmological magnetic fields from Gertsenshtein effect. We adopt a robust perturbative approach and we find that the conversion probability from graviton to photon can be resonantly enhanced in monochromatic, multi-chromatic and scale invariant spectrum models of s...
gr-qc/0006062
Fred C. Adams
Fred C. Adams (Physics Dept., University of Michigan)
The Life and Times of Extremal Black Holes
9 pages, LaTeX, accepted to General Relativity and Gravitation
Gen.Rel.Grav. 32 (2000) 2229-2234
10.1023/A:1001907827388
null
gr-qc
null
Charged extremal black holes cannot fully evaporate through the Hawking effect and are thus long lived. Over their lifetimes, these black holes take part in a variety of astrophysical processes, including many that lead to their eventual destruction. This paper explores the various events that shape the life of extre...
[ { "created": "Fri, 16 Jun 2000 15:53:41 GMT", "version": "v1" } ]
2015-06-25
[ [ "Adams", "Fred C.", "", "Physics Dept., University of Michigan" ] ]
Charged extremal black holes cannot fully evaporate through the Hawking effect and are thus long lived. Over their lifetimes, these black holes take part in a variety of astrophysical processes, including many that lead to their eventual destruction. This paper explores the various events that shape the life of extrema...
1303.1687
Jakub Mielczarek Ph.D.
Jean Pierre Gazeau, Jakub Mielczarek, Wlodzimierz Piechocki
Quantum states of the bouncing universe
18 pages, 19 figures
null
10.1103/PhysRevD.87.123508
null
gr-qc hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we study quantum dynamics of the bouncing cosmological model. We focus on the model of the flat Friedman-Robertson-Walker universe with a free scalar field. The bouncing behavior, which replaces classical singularity, appears due to the modification of general relativity along the methods of loop quantu...
[ { "created": "Thu, 7 Mar 2013 13:34:40 GMT", "version": "v1" } ]
2013-06-12
[ [ "Gazeau", "Jean Pierre", "" ], [ "Mielczarek", "Jakub", "" ], [ "Piechocki", "Wlodzimierz", "" ] ]
In this paper we study quantum dynamics of the bouncing cosmological model. We focus on the model of the flat Friedman-Robertson-Walker universe with a free scalar field. The bouncing behavior, which replaces classical singularity, appears due to the modification of general relativity along the methods of loop quantum ...
gr-qc/9903061
Kristin Schleich
Kristin Schleich and Donald M. Witt
Topological Censorship
Revtex 3, 6 epsf figures. This format differs slightly from that used to produce the article as it originally appeared in the 1994 Proceedings of the Lake Louise Winter Institute. However content is exactly the same
Published in Proceedings of the Lake Louise Winter Institute, Particle Physics and Cosmology, Feb. 20-26, 1994, (World Scientific, 1994)
null
null
gr-qc
null
Classically, all topologies are allowed as solutions to the Einstein equations. However, one does not observe any topological structures on medium range distance scales, that is scales that are smaller than the size of the observed universe but larger than the microscopic scales for which quantum gravity becomes impo...
[ { "created": "Wed, 17 Mar 1999 00:04:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Schleich", "Kristin", "" ], [ "Witt", "Donald M.", "" ] ]
Classically, all topologies are allowed as solutions to the Einstein equations. However, one does not observe any topological structures on medium range distance scales, that is scales that are smaller than the size of the observed universe but larger than the microscopic scales for which quantum gravity becomes import...
gr-qc/0207035
Beverly K. Berger
Beverly K. Berger
Asymptotic Behavior of a Class of Expanding Gowdy Spacetimes
21 pages, 14 figures, uses RevTeX 4, submitted to Phys. Rev. D
null
null
null
gr-qc
null
A systematic asymptotic expansion is developed for the gravitational wave degrees of freedom of a class of expanding, vacuum Gowdy cosmological spacetimes. In the wave map description of these models, the evolution of the gravitational wave amplitudes defines an orbit in the target space. The circumference of this or...
[ { "created": "Sun, 7 Jul 2002 23:35:51 GMT", "version": "v1" } ]
2007-05-23
[ [ "Berger", "Beverly K.", "" ] ]
A systematic asymptotic expansion is developed for the gravitational wave degrees of freedom of a class of expanding, vacuum Gowdy cosmological spacetimes. In the wave map description of these models, the evolution of the gravitational wave amplitudes defines an orbit in the target space. The circumference of this orbi...
1307.0745
Joao Magueijo
Giovanni Amelino-Camelia, Michele Arzano, Giulia Gubitosi and Joao Magueijo
Rainbow gravity and scale-invariant fluctuations
null
Phys. Rev. D 88, 041303, 2013
10.1103/PhysRevD.88.041303
null
gr-qc astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We re-examine a recently proposed scenario where the deformed dispersion relations associated with a flow of the spectral dimension to a UV value of 2 leads to a scale-invariant spectrum of cosmological fluctuations, without the need for inflation. In that scenario Einstein gravity was assumed. The theory displays a ...
[ { "created": "Tue, 2 Jul 2013 16:12:36 GMT", "version": "v1" }, { "created": "Sun, 21 Jul 2013 10:44:54 GMT", "version": "v2" } ]
2015-06-16
[ [ "Amelino-Camelia", "Giovanni", "" ], [ "Arzano", "Michele", "" ], [ "Gubitosi", "Giulia", "" ], [ "Magueijo", "Joao", "" ] ]
We re-examine a recently proposed scenario where the deformed dispersion relations associated with a flow of the spectral dimension to a UV value of 2 leads to a scale-invariant spectrum of cosmological fluctuations, without the need for inflation. In that scenario Einstein gravity was assumed. The theory displays a wa...
1611.08394
Alejandro Perez
Alberto S. Cattaneo and Alejandro Perez
A note on the Poisson bracket of 2d smeared fluxes in loop quantum gravity
5 pages, no figures (journal version)
Class. Quant. Grav. 34, 107001 (2017)
10.1088/1361-6382/aa69b4
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that the non-Abelian nature of geometric fluxes---the corner-stone in the definition of quantum geometry in the framework of loop quantum gravity (LQG)---follows directly form the continuum canonical commutations relations of gravity in connection variables and the validity of the Gauss law. The present treat...
[ { "created": "Fri, 25 Nov 2016 09:29:25 GMT", "version": "v1" }, { "created": "Sat, 1 Apr 2017 22:53:36 GMT", "version": "v2" } ]
2020-02-03
[ [ "Cattaneo", "Alberto S.", "" ], [ "Perez", "Alejandro", "" ] ]
We show that the non-Abelian nature of geometric fluxes---the corner-stone in the definition of quantum geometry in the framework of loop quantum gravity (LQG)---follows directly form the continuum canonical commutations relations of gravity in connection variables and the validity of the Gauss law. The present treatme...
1801.05782
Sean Gryb
Sean Gryb and Karim P. Y. Th\'ebault
Superpositions of the cosmological constant allow for singularity resolution and unitary evolution in quantum cosmology
Version accepted to Physics Letters B. Minor revisions, clarifications added. 7 pages, 3 figures
null
10.1016/j.physletb.2018.08.013
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A novel approach to quantization is shown to allow for superpositions of the cosmological constant in isotropic and homogeneous mini-superspace models. Generic solutions featuring such superpositions display unitary evolution and resolution of the classical singularity. Physically well-motivated cosmological solution...
[ { "created": "Wed, 17 Jan 2018 18:14:40 GMT", "version": "v1" }, { "created": "Tue, 14 Aug 2018 13:21:44 GMT", "version": "v2" } ]
2018-08-15
[ [ "Gryb", "Sean", "" ], [ "Thébault", "Karim P. Y.", "" ] ]
A novel approach to quantization is shown to allow for superpositions of the cosmological constant in isotropic and homogeneous mini-superspace models. Generic solutions featuring such superpositions display unitary evolution and resolution of the classical singularity. Physically well-motivated cosmological solutions ...
2304.03786
Maria Charisi
Maria Charisi, Stephen R. Taylor, Caitlin A. Witt, Jessie Runnoe
Efficient large-scale, targeted gravitational-wave probes of supermassive black-hole binaries
Comments welcome
null
null
null
gr-qc astro-ph.GA astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supermassive black hole binaries are promising sources of low-frequency gravitational waves (GWs) and bright electromagnetic emission. Pulsar timing array searches for resolved binaries are complex and computationally expensive and so far limited to only a few sources. We present an efficient approximation that empow...
[ { "created": "Fri, 7 Apr 2023 18:00:00 GMT", "version": "v1" } ]
2023-04-11
[ [ "Charisi", "Maria", "" ], [ "Taylor", "Stephen R.", "" ], [ "Witt", "Caitlin A.", "" ], [ "Runnoe", "Jessie", "" ] ]
Supermassive black hole binaries are promising sources of low-frequency gravitational waves (GWs) and bright electromagnetic emission. Pulsar timing array searches for resolved binaries are complex and computationally expensive and so far limited to only a few sources. We present an efficient approximation that empower...
1107.1181
Bernard Kelly
Bernard J. Kelly, John G. Baker, William D. Boggs, Sean T. McWilliams, Joan Centrella
Mergers of black-hole binaries with aligned spins: Waveform characteristics
19 pages, 17 figures; new version matches published article
Physical Review D 84:084009 (2011)
10.1103/PhysRevD.84.084009
null
gr-qc astro-ph.GA
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We conduct a descriptive analysis of the multipolar structure of gravitational-radiation waveforms from equal-mass aligned-spin mergers, following an approach first presented in the complementary context of nonspinning black holes of varying mass ratio [J.G. Baker et al. Phys. Rev. D 78 044046 (2008)]. We find that, ...
[ { "created": "Wed, 6 Jul 2011 16:46:41 GMT", "version": "v1" }, { "created": "Wed, 5 Oct 2011 17:13:37 GMT", "version": "v2" } ]
2013-05-29
[ [ "Kelly", "Bernard J.", "" ], [ "Baker", "John G.", "" ], [ "Boggs", "William D.", "" ], [ "McWilliams", "Sean T.", "" ], [ "Centrella", "Joan", "" ] ]
We conduct a descriptive analysis of the multipolar structure of gravitational-radiation waveforms from equal-mass aligned-spin mergers, following an approach first presented in the complementary context of nonspinning black holes of varying mass ratio [J.G. Baker et al. Phys. Rev. D 78 044046 (2008)]. We find that, as...
gr-qc/0611135
Daniel R. Terno
Etera R. Livine and Daniel R. Terno
Quantum causal histories in the light of quantum information
9 pages, 8 eps figures
Phys.Rev.D75:084001,2007
10.1103/PhysRevD.75.084001
null
gr-qc astro-ph hep-th quant-ph
null
We use techniques of quantum information theory to analyze the quantum causal histories approach to quantum gravity. We show that while it is consistent to introduce closed timelike curves (CTCs), they cannot generically carry independent degrees of freedom. Moreover, if the effective dynamics of the chronology-respe...
[ { "created": "Sun, 26 Nov 2006 05:30:30 GMT", "version": "v1" } ]
2008-11-26
[ [ "Livine", "Etera R.", "" ], [ "Terno", "Daniel R.", "" ] ]
We use techniques of quantum information theory to analyze the quantum causal histories approach to quantum gravity. We show that while it is consistent to introduce closed timelike curves (CTCs), they cannot generically carry independent degrees of freedom. Moreover, if the effective dynamics of the chronology-respect...
1003.2105
Mauro Cattani
M.Cattani
Gravitational Waves II: Emitting Systems
null
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use the basic equations that predict the emission of gravitational waves according to the Einstein gravitation theory to calculate the luminosities and the amplitudes of the waves generated by binary stars, pulsations of neutron stars, wobbling of deformed neutron stars, oscillating quadrupoles, rotating bars and ...
[ { "created": "Wed, 10 Mar 2010 13:17:01 GMT", "version": "v1" } ]
2010-03-11
[ [ "Cattani", "M.", "" ] ]
We use the basic equations that predict the emission of gravitational waves according to the Einstein gravitation theory to calculate the luminosities and the amplitudes of the waves generated by binary stars, pulsations of neutron stars, wobbling of deformed neutron stars, oscillating quadrupoles, rotating bars and co...
0812.0533
Valter Moretti
Romeo Brunetti, Lorenzo Franceschini, Valter Moretti (Dept. of Mathematics, Trento U.)
Topological features of massive bosons on two dimensional Einstein space-time
41 pages, title changed, minor changes, typos corrected, references added. Accepted for publication in Ann. Henri Poincare'
Annales Henri Poincare 10:1027-1073,2009
10.1007/s00023-009-0007-x
null
gr-qc hep-th math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we tackle the problem of constructing explicit examples of topological cocycles of Roberts' net cohomology, as defined abstractly by Brunetti and Ruzzi. We consider the simple case of massive bosonic quantum field theory on the two dimensional Einstein cylinder. After deriving some crucial results of th...
[ { "created": "Tue, 2 Dec 2008 16:07:47 GMT", "version": "v1" }, { "created": "Thu, 8 Jan 2009 20:34:11 GMT", "version": "v2" }, { "created": "Fri, 10 Jul 2009 13:58:58 GMT", "version": "v3" } ]
2009-12-15
[ [ "Brunetti", "Romeo", "", "Dept. of\n Mathematics, Trento U." ], [ "Franceschini", "Lorenzo", "", "Dept. of\n Mathematics, Trento U." ], [ "Moretti", "Valter", "", "Dept. of\n Mathematics, Trento U." ] ]
In this paper we tackle the problem of constructing explicit examples of topological cocycles of Roberts' net cohomology, as defined abstractly by Brunetti and Ruzzi. We consider the simple case of massive bosonic quantum field theory on the two dimensional Einstein cylinder. After deriving some crucial results of the ...
1606.06545
Saheb Soroushfar
Bahareh Hoseini, Reza Saffari, Saheb Soroushfar
Geodesic Motion in the Spacetime Of a SU(2)-Colored (A)dS Black Hole in Conformal Gravity
14 pages, 2 table, 18 figures
Eur. Phys. J. Plus 136, 489 (2021)
10.1140/epjp/s13360-021-01511-y
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we study the geodesic motion in the spacetime of a SU(2)-colored (A)dS black hole in conformal gravity, and also we investigate spacetime features, such as light spheres and horizons. Moreover, we derive the analytical solutions for the equation of motion of test particles and light rays using Weierstr...
[ { "created": "Tue, 21 Jun 2016 12:44:15 GMT", "version": "v1" }, { "created": "Wed, 10 Aug 2016 19:49:37 GMT", "version": "v2" }, { "created": "Sat, 15 Jul 2017 21:45:15 GMT", "version": "v3" }, { "created": "Tue, 18 Jul 2017 12:49:38 GMT", "version": "v4" }, { "c...
2021-05-10
[ [ "Hoseini", "Bahareh", "" ], [ "Saffari", "Reza", "" ], [ "Soroushfar", "Saheb", "" ] ]
In this paper, we study the geodesic motion in the spacetime of a SU(2)-colored (A)dS black hole in conformal gravity, and also we investigate spacetime features, such as light spheres and horizons. Moreover, we derive the analytical solutions for the equation of motion of test particles and light rays using Weierstras...
1512.01667
Sunil Maurya DR.
S.K. Maurya, Smitha T. T., Y.K.Gupta, Farook Rahaman
A new exact solution for anisotropic compact stars of embedding class one
16 pages, 12 figures and 3 tables in European physical Journal A - 2016
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have presented a new anisotropic solution of Einstein's field equations for compact star models. The Einstein's field equations are solved by using the class one condition \cite{1}. After that we constructed the physically valid expression of anisotropy factor by the help of metric potentials and there after we ob...
[ { "created": "Sat, 5 Dec 2015 13:47:47 GMT", "version": "v1" }, { "created": "Thu, 28 Jul 2016 21:00:08 GMT", "version": "v2" } ]
2016-08-01
[ [ "Maurya", "S. K.", "" ], [ "T.", "Smitha T.", "" ], [ "Gupta", "Y. K.", "" ], [ "Rahaman", "Farook", "" ] ]
We have presented a new anisotropic solution of Einstein's field equations for compact star models. The Einstein's field equations are solved by using the class one condition \cite{1}. After that we constructed the physically valid expression of anisotropy factor by the help of metric potentials and there after we obta...
1310.2939
Yi-Zen Chu
Yi-Zen Chu
A Line Source in Minkowski for the de Sitter Spacetime Scalar Green's Function: Massive Case
24 pages, 2 figures. v2: Causal structure figures added
null
10.1088/0264-9381/32/13/135008
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For certain classes of space(time)s embeddable in a higher dimensional flat space(time), it appears possible to compute the minimally coupled massless scalar Green's function in the former by convolving its cousin in the latter with an appropriate scalar charge density. The physical interpretation is that beings resi...
[ { "created": "Thu, 10 Oct 2013 20:00:01 GMT", "version": "v1" }, { "created": "Fri, 12 Sep 2014 17:36:44 GMT", "version": "v2" }, { "created": "Wed, 27 May 2015 04:43:47 GMT", "version": "v3" } ]
2015-07-15
[ [ "Chu", "Yi-Zen", "" ] ]
For certain classes of space(time)s embeddable in a higher dimensional flat space(time), it appears possible to compute the minimally coupled massless scalar Green's function in the former by convolving its cousin in the latter with an appropriate scalar charge density. The physical interpretation is that beings residi...
1907.12594
Leandros Perivolaropoulos
F. Skara and L. Perivolaropoulos
Primordial Power Spectra of Cosmological Fluctuations with Generalized Uncertainty Principle and Maximum Length Quantum Mechanics
12 pages, 3 figures. Published version. Comments added, figure added, improved statistical analysis. The Mathematica file that was used for the production of the figures may be downloaded from http://leandros.physics.uoi.gr/GUP-GFC/
Phys. Rev. D 100, 123527 (2019)
10.1103/PhysRevD.100.123527
null
gr-qc astro-ph.CO hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The existence of the cosmological particle horizon as the maximum measurable length $l_{max}$ in the universe leads to a generalization of the quantum uncertainty principle (GUP) to the form $\Delta x \Delta p \geq \frac{\hbar}{2}\frac{1}{1-\alpha\Delta x^2} $, where $\alpha\equiv l_{max}^{-2}$. The effects of this G...
[ { "created": "Mon, 29 Jul 2019 18:18:50 GMT", "version": "v1" }, { "created": "Tue, 6 Aug 2019 05:28:28 GMT", "version": "v2" }, { "created": "Thu, 19 Dec 2019 20:19:53 GMT", "version": "v3" } ]
2019-12-25
[ [ "Skara", "F.", "" ], [ "Perivolaropoulos", "L.", "" ] ]
The existence of the cosmological particle horizon as the maximum measurable length $l_{max}$ in the universe leads to a generalization of the quantum uncertainty principle (GUP) to the form $\Delta x \Delta p \geq \frac{\hbar}{2}\frac{1}{1-\alpha\Delta x^2} $, where $\alpha\equiv l_{max}^{-2}$. The effects of this GUP...
0804.1084
Jonathan R. Gair
Jonathan R Gair, Ilya Mandel, Linqing Wen
Improved time-frequency analysis of extreme-mass-ratio inspiral signals in mock LISA data
8 pages, 1 figure; submitted to proceedings of 12th Gravitational Wave Data Analysis Workshop
Class.Quant.Grav.25:184031,2008
10.1088/0264-9381/25/18/184031
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The planned Laser Interferometer Space Antenna (LISA) is expected to detect gravitational wave signals from ~100 extreme-mass-ratio inspirals (EMRIs) of stellar-mass compact objects into massive black holes. The long duration and large parameter space of EMRI signals makes data analysis for these signals a challengin...
[ { "created": "Mon, 7 Apr 2008 17:12:00 GMT", "version": "v1" } ]
2008-11-26
[ [ "Gair", "Jonathan R", "" ], [ "Mandel", "Ilya", "" ], [ "Wen", "Linqing", "" ] ]
The planned Laser Interferometer Space Antenna (LISA) is expected to detect gravitational wave signals from ~100 extreme-mass-ratio inspirals (EMRIs) of stellar-mass compact objects into massive black holes. The long duration and large parameter space of EMRI signals makes data analysis for these signals a challenging ...
1605.05975
Klaus Liegener
Klaus Liegener and Thomas Thiemann
Towards the fundamental spectrum of the Quantum Yang-Mills Theory
51 pages
Phys. Rev. D 94, 024042 (2016)
10.1103/PhysRevD.94.024042
null
gr-qc hep-lat hep-th math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we focus on the quantum Einstein-Yang-Mills sector quantised by the methods of Loop Quantum Gravity (LQG). We point out the improved UV behaviour of the coupled system as compared to pure quantum Yang-Mills theory on a fixed, classical background spacetime as was considered in a seminal work by Kogut and...
[ { "created": "Thu, 19 May 2016 14:36:12 GMT", "version": "v1" }, { "created": "Thu, 28 Jul 2016 18:00:46 GMT", "version": "v2" } ]
2016-07-29
[ [ "Liegener", "Klaus", "" ], [ "Thiemann", "Thomas", "" ] ]
In this work we focus on the quantum Einstein-Yang-Mills sector quantised by the methods of Loop Quantum Gravity (LQG). We point out the improved UV behaviour of the coupled system as compared to pure quantum Yang-Mills theory on a fixed, classical background spacetime as was considered in a seminal work by Kogut and S...
gr-qc/0601139
Gregor Leiler
Gregor Leiler and Luciano Rezzolla
On the iterated Crank-Nicolson for hyperbolic and parabolic equations in numerical relativity
7 pages, 3 figures
Phys.Rev. D73 (2006) 044001
10.1103/PhysRevD.73.044001
null
gr-qc
null
The iterated Crank-Nicolson is a predictor-corrector algorithm commonly used in numerical relativity for the solution of both hyperbolic and parabolic partial differential equations. We here extend the recent work on the stability of this scheme for hyperbolic equations by investigating the properties when the averag...
[ { "created": "Tue, 31 Jan 2006 10:46:45 GMT", "version": "v1" } ]
2009-11-11
[ [ "Leiler", "Gregor", "" ], [ "Rezzolla", "Luciano", "" ] ]
The iterated Crank-Nicolson is a predictor-corrector algorithm commonly used in numerical relativity for the solution of both hyperbolic and parabolic partial differential equations. We here extend the recent work on the stability of this scheme for hyperbolic equations by investigating the properties when the average ...
1807.11330
Neo Namane
Neo Namane, Heba Sami and Amare Abebe
Oscillating cosmological correlations in f(R) gravity
6 pages, 4 figures, SAIP2018 conference proceedings
null
null
null
gr-qc
http://creativecommons.org/licenses/by-nc-sa/4.0/
The purpose of this paper is to investigate the oscillatory behavior of the universe through a Schr\"odinger-like Friedmann equation and a modified gravitational background described by the theory of f (R) gravity. The motivation for this stems from the observed periodic behaviour of large-scale cosmological structur...
[ { "created": "Mon, 30 Jul 2018 13:05:23 GMT", "version": "v1" } ]
2018-07-31
[ [ "Namane", "Neo", "" ], [ "Sami", "Heba", "" ], [ "Abebe", "Amare", "" ] ]
The purpose of this paper is to investigate the oscillatory behavior of the universe through a Schr\"odinger-like Friedmann equation and a modified gravitational background described by the theory of f (R) gravity. The motivation for this stems from the observed periodic behaviour of large-scale cosmological structures...
1808.03472
Alessia Platania
Ademola Adeifeoba, Astrid Eichhorn, Alessia Platania
Towards conditions for black-hole singularity-resolution in asymptotically safe quantum gravity
12 pages, 1 figure
null
10.1088/1361-6382/aae6ef
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the fate of the curvature singularity of Schwarzschild (deSitter) black holes in asymptotically safe quantum gravity. Specifically, we upgrade the classical spacetime by including the running of the Newton coupling and cosmological constant. In this setting, the antiscreening character of the gravitational...
[ { "created": "Fri, 10 Aug 2018 10:07:20 GMT", "version": "v1" } ]
2018-11-14
[ [ "Adeifeoba", "Ademola", "" ], [ "Eichhorn", "Astrid", "" ], [ "Platania", "Alessia", "" ] ]
We explore the fate of the curvature singularity of Schwarzschild (deSitter) black holes in asymptotically safe quantum gravity. Specifically, we upgrade the classical spacetime by including the running of the Newton coupling and cosmological constant. In this setting, the antiscreening character of the gravitational i...
gr-qc/9905037
Andrew P. Billyard
A. G. Agnese and A. P. Billyard and H. Liu and P. S. Wesson
Possible Wormhole Solutions in (4+1) Gravity
3 pages, latex, 1 figures
Gen.Rel.Grav. 31 (1999) 527-535
10.1023/A:1026646223189
Dal-99-05
gr-qc
null
We extend previous analyses of soliton solutions in (4+1) gravity to new ranges of their defining parameters. The geometry, as studied using invariants, has the topology of wormholes found in (3+1) gravity. In the induced-matter picture, the fluid does not satisfy the strong energy conditions, but its gravitational m...
[ { "created": "Wed, 12 May 1999 14:14:03 GMT", "version": "v1" } ]
2015-06-25
[ [ "Agnese", "A. G.", "" ], [ "Billyard", "A. P.", "" ], [ "Liu", "H.", "" ], [ "Wesson", "P. S.", "" ] ]
We extend previous analyses of soliton solutions in (4+1) gravity to new ranges of their defining parameters. The geometry, as studied using invariants, has the topology of wormholes found in (3+1) gravity. In the induced-matter picture, the fluid does not satisfy the strong energy conditions, but its gravitational mas...
0905.0765
Cornelia Feiler
E. Kajari, M. Buser, C. Feiler and W. P. Schleich
Rotation in relativity and the propagation of light
102 pages, 35 figures, The original publication is available at http://www.sif.it/SIF/en/portal/journals.html, to appear in "Atom Optics and Space Physics", Proceedings of the International School of Physics "Enrico Fermi", Course CLXVIII, edited by E. Arimondo, W. Ertmer, E. M. Rasel and W. P. Schleich, (IOS P...
Proceedings of the International School of Physics "Enrico Fermi", Course CLXVIII, pp. 45-148 (2009)
10.3254/978-1-58603-990-5-45
null
gr-qc quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compare and contrast the different points of view of rotation in general relativity, put forward by Mach, Thirring and Lense, and Goedel. Our analysis relies on two tools: (i) the Sagnac effect which allows us to measure rotations of a coordinate system or induced by the curvature of spacetime, and (ii) computer v...
[ { "created": "Wed, 6 May 2009 08:18:57 GMT", "version": "v1" } ]
2011-08-02
[ [ "Kajari", "E.", "" ], [ "Buser", "M.", "" ], [ "Feiler", "C.", "" ], [ "Schleich", "W. P.", "" ] ]
We compare and contrast the different points of view of rotation in general relativity, put forward by Mach, Thirring and Lense, and Goedel. Our analysis relies on two tools: (i) the Sagnac effect which allows us to measure rotations of a coordinate system or induced by the curvature of spacetime, and (ii) computer vis...
gr-qc/0203096
Friedrich W. Hehl
Friedrich W. Hehl (Cologne), Yuri N. Obukhov (Cologne/Moscow), Guillermo F. Rubilar (Cologne)
On a possible new type of a T odd skewon field linked to electromagnetism
17 pages, LaTeX2e. Invited paper, Proceedings 1st Mexican Meeting on Math. and Exp. Physics, Mexico City, Sept.2001, corrected and slightly updated
null
null
null
gr-qc hep-th
null
In the framework of generally covariant (pre-metric) electrodynamics (``charge & flux electrodynamics''), the Maxwell equations can be formulated in terms of the electromagnetic excitation $H=({\cal D}, {\cal H})$ and the field strength $F=(E,B)$. If the spacetime relation linking $H$ and $F$ is assumed to be {\em li...
[ { "created": "Tue, 26 Mar 2002 23:50:03 GMT", "version": "v1" } ]
2007-05-23
[ [ "Hehl", "Friedrich W.", "", "Cologne" ], [ "Obukhov", "Yuri N.", "", "Cologne/Moscow" ], [ "Rubilar", "Guillermo F.", "", "Cologne" ] ]
In the framework of generally covariant (pre-metric) electrodynamics (``charge & flux electrodynamics''), the Maxwell equations can be formulated in terms of the electromagnetic excitation $H=({\cal D}, {\cal H})$ and the field strength $F=(E,B)$. If the spacetime relation linking $H$ and $F$ is assumed to be {\em line...
1312.3956
Alexander Vilenkin
Alexander Vilenkin and Aron C. Wall
Cosmological singularity theorems and black holes
References added
Phys. Rev. D 89, 064035 (2014)
10.1103/PhysRevD.89.064035
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An extension of Penrose's singularity theorem is proved for spacetimes where black holes are allowed to form from non-singular initial data. With standard assumptions about the spacetime, and assuming the existence of a trapped surface which lies outside of black hole horizons and is not completely surrounded by hori...
[ { "created": "Fri, 13 Dec 2013 21:15:48 GMT", "version": "v1" }, { "created": "Sun, 12 Jan 2014 15:46:20 GMT", "version": "v2" } ]
2014-03-26
[ [ "Vilenkin", "Alexander", "" ], [ "Wall", "Aron C.", "" ] ]
An extension of Penrose's singularity theorem is proved for spacetimes where black holes are allowed to form from non-singular initial data. With standard assumptions about the spacetime, and assuming the existence of a trapped surface which lies outside of black hole horizons and is not completely surrounded by horizo...
2101.07527
Xiangdong Zhang
Xiangdong Zhang, Gaoping Long and Yongge Ma
Loop quantum gravity and cosmological constant
6 pages, 1 figure; v2, accepted by PLB
Physics Letters B 823, (2021) 136770
10.1016/j.physletb.2021.136770
null
gr-qc astro-ph.CO hep-th
http://creativecommons.org/licenses/by/4.0/
An one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as special cases. The quantum bounce nature is tenable in the generalized cases. For...
[ { "created": "Tue, 19 Jan 2021 09:28:23 GMT", "version": "v1" }, { "created": "Wed, 10 Nov 2021 11:44:02 GMT", "version": "v2" } ]
2021-11-12
[ [ "Zhang", "Xiangdong", "" ], [ "Long", "Gaoping", "" ], [ "Ma", "Yongge", "" ] ]
An one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as special cases. The quantum bounce nature is tenable in the generalized cases. For p...
1901.11236
Sayan Kar
Indranil Chakraborty and Sayan Kar (IIT Kharagpur, India)
Geodesic congruences in exact plane wave spacetimes and the memory effect
27 pages, 13 figures, major changes (including title and abstract), rewritten with a different focus, new results added
Phys. Rev. D 101, 064022 (2020)
10.1103/PhysRevD.101.064022
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Displacement and velocity memory effects in the exact, vacuum, plane gravitational wave line element have been studied recently by looking at the behaviour of pairs of geodesics or via geodesic deviation. Instead, one may investigate the evolution of geodesic congruences. In our work here, we obtain the evolution of ...
[ { "created": "Thu, 31 Jan 2019 07:02:02 GMT", "version": "v1" }, { "created": "Wed, 29 May 2019 10:46:26 GMT", "version": "v2" }, { "created": "Mon, 25 Nov 2019 09:57:23 GMT", "version": "v3" }, { "created": "Sat, 14 Mar 2020 04:59:34 GMT", "version": "v4" } ]
2020-03-18
[ [ "Chakraborty", "Indranil", "", "IIT Kharagpur, India" ], [ "Kar", "Sayan", "", "IIT Kharagpur, India" ] ]
Displacement and velocity memory effects in the exact, vacuum, plane gravitational wave line element have been studied recently by looking at the behaviour of pairs of geodesics or via geodesic deviation. Instead, one may investigate the evolution of geodesic congruences. In our work here, we obtain the evolution of th...
2010.06386
Rustam Gainutdinov
Rustam Gainutdinov and Yurij Baryshev
Relativistic effects in orbital motion of the S-stars at the Galactic Center
Accepted for publication in the journal Universe, 08.10.2020
Universe 2020, 6(10), 177
10.3390/universe6100177
null
gr-qc astro-ph.GA
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Galactic Center star cluster, known as S-stars, is a perfect source of relativistic phenomena observations. The stars are located in the strong field of relativistic compact object Sgr A* and are moving with very high velocities at pericenters of their orbits. In this work we consider motion of several S-stars by...
[ { "created": "Sat, 10 Oct 2020 04:41:56 GMT", "version": "v1" } ]
2020-10-15
[ [ "Gainutdinov", "Rustam", "" ], [ "Baryshev", "Yurij", "" ] ]
The Galactic Center star cluster, known as S-stars, is a perfect source of relativistic phenomena observations. The stars are located in the strong field of relativistic compact object Sgr A* and are moving with very high velocities at pericenters of their orbits. In this work we consider motion of several S-stars by u...
1512.07017
Nilanjana Mahata
Nilanjana Mahata and Subenoy Chakraborty
A Dynamical System Analysis of Three Fluid cosmological Model
10 pages, 7 figures
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In Friedman-Robertson-Walker flat spacetime, we consider a three fluid cosmological model which contains dark matter, dark energy and baryonic matter in the form of perfect fluid with a barotropic equation of state. Dark matter is taken in form of dust and dark energy is described by a scalar field with a potential $...
[ { "created": "Tue, 22 Dec 2015 10:21:11 GMT", "version": "v1" } ]
2015-12-23
[ [ "Mahata", "Nilanjana", "" ], [ "Chakraborty", "Subenoy", "" ] ]
In Friedman-Robertson-Walker flat spacetime, we consider a three fluid cosmological model which contains dark matter, dark energy and baryonic matter in the form of perfect fluid with a barotropic equation of state. Dark matter is taken in form of dust and dark energy is described by a scalar field with a potential $V(...
1311.4443
Sebastiano Bernuzzi
Sebastiano Bernuzzi, Tim Dietrich, Wolfgang Tichy, and Bernd Bruegmann
Mergers of binary neutron stars with realistic spin
null
Phys. Rev. D 89, 104021 (2014)
10.1103/PhysRevD.89.104021
null
gr-qc astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Simulations of binary neutron stars have seen great advances in terms of physical detail and numerical quality. However, the spin of the neutron stars, one of the simplest global parameters of binaries, remains mostly unstudied. We present the first, fully nonlinear general relativistic dynamical evolutions of the la...
[ { "created": "Mon, 18 Nov 2013 16:35:30 GMT", "version": "v1" }, { "created": "Fri, 6 Jun 2014 14:10:27 GMT", "version": "v2" } ]
2015-04-15
[ [ "Bernuzzi", "Sebastiano", "" ], [ "Dietrich", "Tim", "" ], [ "Tichy", "Wolfgang", "" ], [ "Bruegmann", "Bernd", "" ] ]
Simulations of binary neutron stars have seen great advances in terms of physical detail and numerical quality. However, the spin of the neutron stars, one of the simplest global parameters of binaries, remains mostly unstudied. We present the first, fully nonlinear general relativistic dynamical evolutions of the last...
gr-qc/0005079
Bahram Mashhoon
Hongya Liu (Dalian University of Technology, China), and Bahram Mashhoon (University of Missouri-Columbia, USA)
Spacetime Measurements in Kaluza-Klein Gravity
LaTeX, 12 pages, no figures, 2 references added, to appear in Phys. Lett. A
Phys.Lett. A272 (2000) 26-31
10.1016/S0375-9601(00)00407-2
null
gr-qc
null
We extend the classical general relativistic theory of measurement to include the possibility of existence of higher dimensions. The intrusion of these dimensions in the spacetime interval implies that the inertial mass of a particle in general varies along its worldline if the observations are analyzed assuming the ...
[ { "created": "Thu, 18 May 2000 00:44:39 GMT", "version": "v1" }, { "created": "Thu, 25 May 2000 21:34:15 GMT", "version": "v2" } ]
2009-10-31
[ [ "Liu", "Hongya", "", "Dalian University of Technology, China" ], [ "Mashhoon", "Bahram", "", "University of Missouri-Columbia, USA" ] ]
We extend the classical general relativistic theory of measurement to include the possibility of existence of higher dimensions. The intrusion of these dimensions in the spacetime interval implies that the inertial mass of a particle in general varies along its worldline if the observations are analyzed assuming the ex...
gr-qc/9712089
Yuri N. Obukhov
Friedrich W. Hehl and Yuri N. Obukhov
Is a `hadronic' shear current one of the sources in metric-affine gravity?
Latex, mprocl.sty, 3 pages. Contribution to 8th Marcel Grossmann meeting, Jerusalem 1997
null
null
null
gr-qc
null
The Minkowski space of special relativity can be understood as a flat 4-dimensional affine space enriched by a constant Minkowski metric. If we gauge the general affine group and `superimpose' the metric, then we arrive at the metric-affine theory of gravity (MAG). The gravitational potentials are the spacetime cofra...
[ { "created": "Tue, 23 Dec 1997 16:38:57 GMT", "version": "v1" } ]
2007-05-23
[ [ "Hehl", "Friedrich W.", "" ], [ "Obukhov", "Yuri N.", "" ] ]
The Minkowski space of special relativity can be understood as a flat 4-dimensional affine space enriched by a constant Minkowski metric. If we gauge the general affine group and `superimpose' the metric, then we arrive at the metric-affine theory of gravity (MAG). The gravitational potentials are the spacetime coframe...
gr-qc/0311056
Mariano Cadoni
Mariano Cadoni
Black Hole fragmentation and holography
7 pages, no figures
Phys.Rev. D69 (2004) 084021
10.1103/PhysRevD.69.084021
INFNCA-TH0304
gr-qc hep-th
null
We discuss the entropy change due to fragmentation for black hole solutions in various dimensions. We find three different types of behavior. The entropy may decrease, increase or have a mixed behavior, characterized by the presence of a threshold mass. For two-dimensional (2D) black holes we give a complete characte...
[ { "created": "Tue, 18 Nov 2003 13:33:00 GMT", "version": "v1" } ]
2009-11-10
[ [ "Cadoni", "Mariano", "" ] ]
We discuss the entropy change due to fragmentation for black hole solutions in various dimensions. We find three different types of behavior. The entropy may decrease, increase or have a mixed behavior, characterized by the presence of a threshold mass. For two-dimensional (2D) black holes we give a complete characteri...
1909.05811
Philip Tee
Philip Tee
Dynamics and the Emergence of Geometry in an Information Mesh
null
null
10.1140/epjc/s10052-020-8282-2
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The idea of a graph theoretical approach to modeling the emergence of a quantized geometry and consequently spacetime, has been proposed previously, but not well studied. In most approaches the focus has been upon how to generate a spacetime that possesses properties that would be desirable at the continuum limit, an...
[ { "created": "Thu, 12 Sep 2019 17:13:04 GMT", "version": "v1" }, { "created": "Thu, 30 Apr 2020 22:24:14 GMT", "version": "v2" }, { "created": "Mon, 27 Jul 2020 14:50:10 GMT", "version": "v3" }, { "created": "Sun, 25 Apr 2021 23:06:09 GMT", "version": "v4" } ]
2021-04-27
[ [ "Tee", "Philip", "" ] ]
The idea of a graph theoretical approach to modeling the emergence of a quantized geometry and consequently spacetime, has been proposed previously, but not well studied. In most approaches the focus has been upon how to generate a spacetime that possesses properties that would be desirable at the continuum limit, and ...
1005.5670
Yousef Bisabr
Yousef Bisabr
Local Gravity Constraints and Power Law f(R) Theories
11 Pages, no figure. To appear in Gravitation and Cosmology
Grav.Cosmol.16:239-244,2010
10.1134/S0202289310030084
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There is a conformal equivalence between power law $f(R)$ theories and scalar field theories in which the scalar degree of freedom evolves under the action of an exponential potential function. In the scalar field representation there is a strong coupling of the scalar field with the matter sector due to the conforma...
[ { "created": "Mon, 31 May 2010 12:25:17 GMT", "version": "v1" } ]
2014-11-21
[ [ "Bisabr", "Yousef", "" ] ]
There is a conformal equivalence between power law $f(R)$ theories and scalar field theories in which the scalar degree of freedom evolves under the action of an exponential potential function. In the scalar field representation there is a strong coupling of the scalar field with the matter sector due to the conformal ...
gr-qc/9409014
null
D. Giulini and C. Kiefer
Consistency of Semiclassical Gravity
12 pages, LATEX, Report Freiburg THEP-94/20
Class.Quant.Grav.12:403-412,1995
10.1088/0264-9381/12/2/009
null
gr-qc
null
We discuss some subtleties which arise in the semiclassical approximation to quantum gravity. We show that integrability conditions prevent the existence of Tomonaga-Schwinger time functions on the space of three-metrics but admit them on superspace. The concept of semiclassical time is carefully examined. We point o...
[ { "created": "Thu, 8 Sep 1994 08:00:42 GMT", "version": "v1" } ]
2010-04-06
[ [ "Giulini", "D.", "" ], [ "Kiefer", "C.", "" ] ]
We discuss some subtleties which arise in the semiclassical approximation to quantum gravity. We show that integrability conditions prevent the existence of Tomonaga-Schwinger time functions on the space of three-metrics but admit them on superspace. The concept of semiclassical time is carefully examined. We point out...
1307.1603
Stefan Hollands
Stefan Hollands, Alexander Thorne
Bondi mass cannot become negative in higher dimensions
19 pages, Latex, no figures, v2: Introduction partly reorganized, minor corrections
null
10.1007/s00220-014-2096-8
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We prove that the Bondi mass of an asymptotically flat, vacuum, spacetime cannot become negative in any even dimension $d \ge 4$. The notion of Bondi mass is more subtle in $d > 4$ dimensions because radiating metrics have a slower decay than stationary ones, and those subtleties are reflected by a considerably more ...
[ { "created": "Fri, 5 Jul 2013 13:05:32 GMT", "version": "v1" }, { "created": "Mon, 27 Jan 2014 11:40:39 GMT", "version": "v2" } ]
2015-06-16
[ [ "Hollands", "Stefan", "" ], [ "Thorne", "Alexander", "" ] ]
We prove that the Bondi mass of an asymptotically flat, vacuum, spacetime cannot become negative in any even dimension $d \ge 4$. The notion of Bondi mass is more subtle in $d > 4$ dimensions because radiating metrics have a slower decay than stationary ones, and those subtleties are reflected by a considerably more di...
2309.15853
Salim Shekh Dr.
S. H. Shekh, Hira Sohail, Irfan Mahmood, Allah Ditta, Anil Kumar Yadav
Models of f(Q) gravity with electromagnetic field
pages-16, Figures-0,
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There are so many ideas that potentially explain the dark energy phenomenon, current research is focusing on a more in-depth analysis of the potential effects of modified gravity on both local and cosmic scales. In this paper we have investigated some cosmic reconstructions in $f (Q)$ cosmology where $Q$ is the non-m...
[ { "created": "Thu, 31 Aug 2023 16:16:45 GMT", "version": "v1" } ]
2023-09-29
[ [ "Shekh", "S. H.", "" ], [ "Sohail", "Hira", "" ], [ "Mahmood", "Irfan", "" ], [ "Ditta", "Allah", "" ], [ "Yadav", "Anil Kumar", "" ] ]
There are so many ideas that potentially explain the dark energy phenomenon, current research is focusing on a more in-depth analysis of the potential effects of modified gravity on both local and cosmic scales. In this paper we have investigated some cosmic reconstructions in $f (Q)$ cosmology where $Q$ is the non-met...
2211.07469
Alejandro C\'ardenas-Avenda\~no
Alejandro C\'ardenas-Avenda\~no, Alexandru Lupsasca, Hengrui Zhu
Adaptive Analytical Ray Tracing of Black Hole Photon Rings
39 pages, 16 figures. Updated to match published version. V4: corrected two very minor typos (in Eqs. 50 and 70)
Phys. Rev. D 107, 043030, 2023
10.1103/PhysRevD.107.043030
null
gr-qc astro-ph.HE
http://creativecommons.org/licenses/by/4.0/
Recent interferometric observations by the Event Horizon Telescope have resolved the horizon-scale emission from sources in the vicinity of nearby supermassive black holes. Future space-based interferometers promise to measure the "photon ring"--a narrow, ring-shaped, lensed feature predicted by general relativity, b...
[ { "created": "Mon, 14 Nov 2022 15:51:50 GMT", "version": "v1" }, { "created": "Tue, 7 Feb 2023 17:26:29 GMT", "version": "v2" }, { "created": "Wed, 22 Feb 2023 16:11:17 GMT", "version": "v3" }, { "created": "Tue, 4 Jun 2024 23:14:52 GMT", "version": "v4" } ]
2024-06-06
[ [ "Cárdenas-Avendaño", "Alejandro", "" ], [ "Lupsasca", "Alexandru", "" ], [ "Zhu", "Hengrui", "" ] ]
Recent interferometric observations by the Event Horizon Telescope have resolved the horizon-scale emission from sources in the vicinity of nearby supermassive black holes. Future space-based interferometers promise to measure the "photon ring"--a narrow, ring-shaped, lensed feature predicted by general relativity, but...
gr-qc/0307090
Enrique Alvarez
Enrique \'Alvarez (IFT UAM/CSIC, Madrid)
Loops versus strings
19 pages. Talk given in the meeting "What comes beyond the standard model?", Portoroz, Eslovenia, 12-17 July 2003
null
null
IFT-UAM/CSIC-03-23
gr-qc hep-th
null
Two popular attempts to understand the quantum physics of gravitation are critically assessed. The talk on which this paper is based was intended for a general particle-physics audience.
[ { "created": "Mon, 21 Jul 2003 09:22:07 GMT", "version": "v1" }, { "created": "Thu, 24 Jul 2003 11:25:48 GMT", "version": "v2" } ]
2007-05-23
[ [ "Álvarez", "Enrique", "", "IFT UAM/CSIC, Madrid" ] ]
Two popular attempts to understand the quantum physics of gravitation are critically assessed. The talk on which this paper is based was intended for a general particle-physics audience.
gr-qc/0406076
Alessandro D. A. M. Spallicci
Alessandro D.A.M. Spallicci, Sofiane Aoudia, Jose De Freitas Pacheco, Giorgio Frossati, Tania Regimbau
Advanced VIRGO: detector optimization for gravitational waves by inspiralling binaries
Change of title (Virgo detector optimization for gravitational waves by coalescing binaries) and partially of text. 6 figures
Class.Quant.Grav. 22 (2005) S461-S469
10.1088/0264-9381/22/10/044
null
gr-qc
null
For future configurations, we study the relation between the abatement of the noise sources and the Signal to Noise Ratio (SNR) for coalescing binaries. Our aim is not the proposition of a new design, but an indication of where in the bandwidth or for which noise source, a noise reduction would be most efficient. We ...
[ { "created": "Sun, 20 Jun 2004 09:53:21 GMT", "version": "v1" }, { "created": "Sun, 12 Dec 2004 21:59:05 GMT", "version": "v2" }, { "created": "Tue, 14 Jun 2005 23:36:45 GMT", "version": "v3" } ]
2009-11-10
[ [ "Spallicci", "Alessandro D. A. M.", "" ], [ "Aoudia", "Sofiane", "" ], [ "Pacheco", "Jose De Freitas", "" ], [ "Frossati", "Giorgio", "" ], [ "Regimbau", "Tania", "" ] ]
For future configurations, we study the relation between the abatement of the noise sources and the Signal to Noise Ratio (SNR) for coalescing binaries. Our aim is not the proposition of a new design, but an indication of where in the bandwidth or for which noise source, a noise reduction would be most efficient. We ta...
1306.6299
Alessandro Nagar
Alessandro Nagar
Gravitational recoil in nonspinning black hole binaries: the span of test-mass results
5 pages, 3 figures. Matches published version
Physical Review D 88, 121501 (R), 2013
10.1103/PhysRevD.88.121501
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider binary systems of coalescing, nonspinning, black holes of masses $m_{1}$ and $m_{2}$ and show that the gravitational recoil velocity for any mass ratio can be obtained accurately by extrapolating the waveform of the test-mass limit case. The waveform obtained in the limit $m_1/m_2\ll 1$ via a perturbative...
[ { "created": "Wed, 26 Jun 2013 17:45:26 GMT", "version": "v1" }, { "created": "Mon, 16 Dec 2013 22:27:26 GMT", "version": "v2" } ]
2015-06-16
[ [ "Nagar", "Alessandro", "" ] ]
We consider binary systems of coalescing, nonspinning, black holes of masses $m_{1}$ and $m_{2}$ and show that the gravitational recoil velocity for any mass ratio can be obtained accurately by extrapolating the waveform of the test-mass limit case. The waveform obtained in the limit $m_1/m_2\ll 1$ via a perturbative a...
0704.2508
Paul Tod
Paul Tod
Analyticity of strictly static and strictly stationary, inheriting and non-inheriting Einstein-Maxwell solutions
11 pages; to appear in Gen.Rel.Grav
Gen.Rel.Grav.39:1031-1042,2007
10.1007/s10714-007-0436-0
null
gr-qc
null
Following the technique of M\"uller-zum-Hagen, refs [1,2], we show that strictly static and strictly stationary solutions of the Einstein-Maxwell equations are analytic in harmonic coordinates. This holds whether or not the Maxwell field inherits the symmetry.
[ { "created": "Thu, 19 Apr 2007 11:23:29 GMT", "version": "v1" } ]
2008-11-26
[ [ "Tod", "Paul", "" ] ]
Following the technique of M\"uller-zum-Hagen, refs [1,2], we show that strictly static and strictly stationary solutions of the Einstein-Maxwell equations are analytic in harmonic coordinates. This holds whether or not the Maxwell field inherits the symmetry.
2310.13405
Federico Stachurski Mr.
Federico Stachurski, Christopher Messenger, Martin Hendry
Cosmological Inference using Gravitational Waves and Normalising Flows
5 pages, 2 figures, to be submitted to Physics Review Letters (PRL)
null
null
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
We present a machine learning approach using normalising flows for inferring cosmological parameters from gravitational wave events. Our methodology is general to any type of compact binary coalescence event and cosmological model and relies on the generation of training data representing distributions of gravitation...
[ { "created": "Fri, 20 Oct 2023 10:23:41 GMT", "version": "v1" }, { "created": "Wed, 25 Oct 2023 16:46:10 GMT", "version": "v2" } ]
2023-10-26
[ [ "Stachurski", "Federico", "" ], [ "Messenger", "Christopher", "" ], [ "Hendry", "Martin", "" ] ]
We present a machine learning approach using normalising flows for inferring cosmological parameters from gravitational wave events. Our methodology is general to any type of compact binary coalescence event and cosmological model and relies on the generation of training data representing distributions of gravitational...
2011.13499
Daniel Flores
D. Flores-Alfonso, C. S. Lopez-Monsalvo, M. Maceda
Contact Geometry in Superconductors and New Massive Gravity
null
Phys. Lett. B 815 (2021) 136143
10.1016/j.physletb.2021.136143
null
gr-qc hep-th math-ph math.MP
http://creativecommons.org/licenses/by/4.0/
The defining property of every three-dimensional $\varepsilon$-contact manifold is shown to be equivalent to requiring the fulfillment of London's equation in 2+1 electromagnetism. To illustrate this point, we show that every such manifold that is also K-contact and $\eta$-Einstein is a vacuum solution to the most ge...
[ { "created": "Thu, 26 Nov 2020 23:52:03 GMT", "version": "v1" }, { "created": "Wed, 2 Dec 2020 23:33:58 GMT", "version": "v2" }, { "created": "Mon, 22 Feb 2021 15:29:08 GMT", "version": "v3" } ]
2021-02-23
[ [ "Flores-Alfonso", "D.", "" ], [ "Lopez-Monsalvo", "C. S.", "" ], [ "Maceda", "M.", "" ] ]
The defining property of every three-dimensional $\varepsilon$-contact manifold is shown to be equivalent to requiring the fulfillment of London's equation in 2+1 electromagnetism. To illustrate this point, we show that every such manifold that is also K-contact and $\eta$-Einstein is a vacuum solution to the most gene...
1904.11089
Huan Yang
Huan Yang
Inspiralling eccentric binary neutron stars: orbital motion and tidal resonance
18 pages, 1 figure
Phys. Rev. D 100, 064023 (2019)
10.1103/PhysRevD.100.064023
null
gr-qc astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the orbital evolution of eccentric binary neutron stars. The orbit is described as a Quasi-Keplarian orbit with perturbations due to tidal couplings. We find that the tidal interaction between stars contributes to orbital precession, in addition to the Post-Newtonian procession. The coupling between the angu...
[ { "created": "Wed, 24 Apr 2019 22:39:01 GMT", "version": "v1" }, { "created": "Wed, 18 Sep 2019 13:37:14 GMT", "version": "v2" } ]
2019-09-25
[ [ "Yang", "Huan", "" ] ]
We study the orbital evolution of eccentric binary neutron stars. The orbit is described as a Quasi-Keplarian orbit with perturbations due to tidal couplings. We find that the tidal interaction between stars contributes to orbital precession, in addition to the Post-Newtonian procession. The coupling between the angula...
2307.15384
Xiangdong Zhang
Wenxi Zhai and Xiangdong Zhang
Gauss-Bonnet solution with a cloud of strings in de Sitter and anti-de Sitter space
16 pages, 7 figures
Chinese Physics C Vol. 48, No. 1 (2024) 015101
10.1088/1674-1137/ad010d
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
In this paper, we present exact spherically symmetric Gauss-Bonnet black hole solutions surrounded by a cloud of strings fluid with cosmological constant in $D>4$ dimensions. Both charged and uncharged cases are considered. We focus on the de Sitter solutions in the main text and leave the Anti-de Sitter solutions in...
[ { "created": "Fri, 28 Jul 2023 08:14:24 GMT", "version": "v1" } ]
2023-12-27
[ [ "Zhai", "Wenxi", "" ], [ "Zhang", "Xiangdong", "" ] ]
In this paper, we present exact spherically symmetric Gauss-Bonnet black hole solutions surrounded by a cloud of strings fluid with cosmological constant in $D>4$ dimensions. Both charged and uncharged cases are considered. We focus on the de Sitter solutions in the main text and leave the Anti-de Sitter solutions in t...
1711.07730
Qiang Wang
Jianfeng Su and Qiang Wang and Qinghua Wang and Philippe Jetzer
Low-frequency Gravitational Wave Detection via Double Optical Clocks in Space
18 pages, 2 figures
null
10.1088/1361-6382/aab2eb
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a Doppler tracking system for gravitational wave detection via Double Optical Clocks in Space (DOCS). In this configuration two spacecrafts (each containing an optical clock) are launched to space for Doppler shift observations. Compared to the similar attempt of gravitational wave detection in the Cassini...
[ { "created": "Tue, 21 Nov 2017 11:43:14 GMT", "version": "v1" }, { "created": "Tue, 13 Feb 2018 11:33:48 GMT", "version": "v2" } ]
2018-04-18
[ [ "Su", "Jianfeng", "" ], [ "Wang", "Qiang", "" ], [ "Wang", "Qinghua", "" ], [ "Jetzer", "Philippe", "" ] ]
We propose a Doppler tracking system for gravitational wave detection via Double Optical Clocks in Space (DOCS). In this configuration two spacecrafts (each containing an optical clock) are launched to space for Doppler shift observations. Compared to the similar attempt of gravitational wave detection in the Cassini m...
gr-qc/0312019
Stoytcho Yazadjiev
Stoytcho S. Yazadjiev (Sofia University)
Interior perfect fluid scalar-tensor solution
8 pages, 3 figures, LaTex
Phys.Rev. D69 (2004) 127501
10.1103/PhysRevD.69.127501
null
gr-qc
null
We present a new exact perfect fluid interior solution for a particular scalar-tensor theory. The solution is regular everywhere and has a well defined boundary where the fluid pressure vanishes. The metric and the dilaton field match continuously the external solution.
[ { "created": "Wed, 3 Dec 2003 08:25:17 GMT", "version": "v1" } ]
2009-11-10
[ [ "Yazadjiev", "Stoytcho S.", "", "Sofia University" ] ]
We present a new exact perfect fluid interior solution for a particular scalar-tensor theory. The solution is regular everywhere and has a well defined boundary where the fluid pressure vanishes. The metric and the dilaton field match continuously the external solution.
gr-qc/9307014
Gary Horowitz
Dieter Brill, Gary Horowitz, David Kastor, and Jennie Traschen
Testing Cosmic Censorship with Black Hole Collisions
30 pages, 8 figs., phyzzx
Phys.Rev. D49 (1994) 840-852
10.1103/PhysRevD.49.840
null
gr-qc hep-th
null
There exists an upper limit on the mass of black holes when the cosmological constant $\Lambda$ is positive. We study the collision of two black holes whose total mass exceeds this limit. Our investigation is based on a recently discovered exact solution describing the collision of $Q=M$ black holes with $\Lambda > 0...
[ { "created": "Mon, 12 Jul 1993 20:32:44 GMT", "version": "v1" } ]
2009-10-22
[ [ "Brill", "Dieter", "" ], [ "Horowitz", "Gary", "" ], [ "Kastor", "David", "" ], [ "Traschen", "Jennie", "" ] ]
There exists an upper limit on the mass of black holes when the cosmological constant $\Lambda$ is positive. We study the collision of two black holes whose total mass exceeds this limit. Our investigation is based on a recently discovered exact solution describing the collision of $Q=M$ black holes with $\Lambda > 0$....
gr-qc/9512047
Sergey Solodukhin
A.O. Barvinsky and S.N. Solodukhin
Non-minimal coupling, boundary terms and renormalization of the Einstein-Hilbert action
14 pages, latex. More discussion added, the case of 2D Maxwell field considered in more details
Nucl.Phys. B479 (1996) 305-318
10.1016/0550-3213(96)00438-5
WATPHYS-TH-95-11
gr-qc hep-th
null
A consistent variational procedure applied to the gravitational action requires according to Gibbons and Hawking a certain balance between the volume and boundary parts of the action. We consider the problem of preserving this balance in the quantum effective action for the matter non-minimally coupled to metric. It ...
[ { "created": "Thu, 28 Dec 1995 23:36:18 GMT", "version": "v1" }, { "created": "Wed, 24 Jul 1996 19:59:32 GMT", "version": "v2" } ]
2009-10-28
[ [ "Barvinsky", "A. O.", "" ], [ "Solodukhin", "S. N.", "" ] ]
A consistent variational procedure applied to the gravitational action requires according to Gibbons and Hawking a certain balance between the volume and boundary parts of the action. We consider the problem of preserving this balance in the quantum effective action for the matter non-minimally coupled to metric. It is...
1901.05449
S Habib Mazharimousavi
S. Habib Mazharimousavi and M. Halilsoy
Einstein-non-linear Maxwell-Yukawa black hole
8 pages, 6 figures
null
10.1142/S0218271819501207
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within the context of nonlinear electromagnetism we consider the Yukawa extension of a Reissner-Nordstr\"{o}m black hole. Exact solution is given which modifies certain characteristics of the latter. Some thermodynamical aspects are given for comparison. The model may be considered as a useful agent to describe a sho...
[ { "created": "Wed, 16 Jan 2019 12:22:11 GMT", "version": "v1" } ]
2019-07-24
[ [ "Mazharimousavi", "S. Habib", "" ], [ "Halilsoy", "M.", "" ] ]
Within the context of nonlinear electromagnetism we consider the Yukawa extension of a Reissner-Nordstr\"{o}m black hole. Exact solution is given which modifies certain characteristics of the latter. Some thermodynamical aspects are given for comparison. The model may be considered as a useful agent to describe a short...
2405.10604
Nandan Roy
Chonticha Kritpetch, Nandan Roy and Narayan Banerjee
Interacting dark sector: a dynamical system perspective
19 pages, 8 figures
null
null
null
gr-qc astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
We investigate the interaction between the dark sectors from a dynamical systems perspective. A general setup for interacting dark energy models that incorporates both quintessence and phantom fields through a switch parameter, allowing an interaction in the dark sectors has been considered. In the first part of our ...
[ { "created": "Fri, 17 May 2024 07:59:11 GMT", "version": "v1" } ]
2024-05-20
[ [ "Kritpetch", "Chonticha", "" ], [ "Roy", "Nandan", "" ], [ "Banerjee", "Narayan", "" ] ]
We investigate the interaction between the dark sectors from a dynamical systems perspective. A general setup for interacting dark energy models that incorporates both quintessence and phantom fields through a switch parameter, allowing an interaction in the dark sectors has been considered. In the first part of our an...
2206.03828
Rituparno Goswami
Sayuri Singh, Dharmanand Baboolal, Rituparno Goswami, Sunil D. Maharaj
Gaussian curvature of spherical shells: A geometric measure of complexity
8 pages, 1 figure, Revtex 4
null
10.1088/1361-6382/ac9efe
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we consider a semitetrad covariant decomposition of spherically symmetric spacetimes and find a governing hyperbolic equation of the Gaussian curvature of two dimensional spherical shells, that emerges due to the decomposition. The restoration factor of this hyperbolic travelling wave equation allows us...
[ { "created": "Wed, 8 Jun 2022 11:58:05 GMT", "version": "v1" } ]
2022-11-23
[ [ "Singh", "Sayuri", "" ], [ "Baboolal", "Dharmanand", "" ], [ "Goswami", "Rituparno", "" ], [ "Maharaj", "Sunil D.", "" ] ]
In this paper we consider a semitetrad covariant decomposition of spherically symmetric spacetimes and find a governing hyperbolic equation of the Gaussian curvature of two dimensional spherical shells, that emerges due to the decomposition. The restoration factor of this hyperbolic travelling wave equation allows us t...
gr-qc/0703115
Jose M. M. Senovilla
Jos\'e M M Senovilla
Classification of spacelike surfaces in spacetime
42 pages, 10 tables, many diagrams
Class.Quant.Grav.24:3091-3124,2007
10.1088/0264-9381/24/11/020
null
gr-qc math.DG
null
A classification of 2-dimensional surfaces imbedded in spacetime is presented, according to the algebraic properties of their shape tensor. The classification has five levels, and provides among other things a refinement of the concepts of trapped, umbilical and extremal surfaces, which split into several different c...
[ { "created": "Thu, 22 Mar 2007 17:48:48 GMT", "version": "v1" } ]
2008-11-26
[ [ "Senovilla", "José M M", "" ] ]
A classification of 2-dimensional surfaces imbedded in spacetime is presented, according to the algebraic properties of their shape tensor. The classification has five levels, and provides among other things a refinement of the concepts of trapped, umbilical and extremal surfaces, which split into several different cla...
gr-qc/0612078
Ari Peltola
Jarmo Makela and Ari Peltola
Gravitation and Thermodynamics: The Einstein Equation of State Revisited
17 pages, 2 figures. Final version, accepted for publication in IJMPD. The paper has been re-organized, and significantly re-written, although the conclusions remain essentially the same
Int.J.Mod.Phys.D18:669-689,2009
10.1142/S0218271809014698
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform an analysis where Einstein's field equation is derived by means of very simple thermodynamical arguments. Our derivation is based on a consideration of the properties of a very small, spacelike two-plane in a uniformly accelerating motion.
[ { "created": "Wed, 13 Dec 2006 10:28:38 GMT", "version": "v1" }, { "created": "Thu, 10 May 2007 13:57:20 GMT", "version": "v2" }, { "created": "Tue, 19 Aug 2008 16:11:38 GMT", "version": "v3" } ]
2010-11-11
[ [ "Makela", "Jarmo", "" ], [ "Peltola", "Ari", "" ] ]
We perform an analysis where Einstein's field equation is derived by means of very simple thermodynamical arguments. Our derivation is based on a consideration of the properties of a very small, spacelike two-plane in a uniformly accelerating motion.
gr-qc/9710035
Jai-chan Hwang
J. Hwang and H. Noh
Cosmological Vorticity in a Gravity with Quadratic Order Curvature Couplings
5 pages, revtex, no figures
Phys.Rev.D57:2617-2620,1998
10.1103/PhysRevD.57.2617
null
gr-qc
null
We analyse the evolution of the rotational type cosmological perturbation in a gravity with general quadratic order gravitational coupling terms. The result is expressed independently of the generalized nature of the gravity theory, and is simply interpreted as a conservation of the angular momentum.
[ { "created": "Tue, 7 Oct 1997 04:44:04 GMT", "version": "v1" } ]
2010-11-19
[ [ "Hwang", "J.", "" ], [ "Noh", "H.", "" ] ]
We analyse the evolution of the rotational type cosmological perturbation in a gravity with general quadratic order gravitational coupling terms. The result is expressed independently of the generalized nature of the gravity theory, and is simply interpreted as a conservation of the angular momentum.
gr-qc/9902009
Amir H. Abbassi
Amir H. Abbassi
Non-Static Spherically Symmetric solution of Einstein vacuum Field Equations with $Lambda$
9pages,no figures, Latex
JHEP 9904 (1999) 011
10.1088/1126-6708/1999/04/011
null
gr-qc
null
The Schwarzschild-deSitter metric is the known solution of Einstein field equations with cosmological constant term for vacuum spherically symmetric space around a point mass M. Recently it has been reported that in a $Lamda$-dominant world the Schwarzschild type coordinate systems are disqualified by redshift-magnit...
[ { "created": "Tue, 2 Feb 1999 17:50:30 GMT", "version": "v1" } ]
2009-10-31
[ [ "Abbassi", "Amir H.", "" ] ]
The Schwarzschild-deSitter metric is the known solution of Einstein field equations with cosmological constant term for vacuum spherically symmetric space around a point mass M. Recently it has been reported that in a $Lamda$-dominant world the Schwarzschild type coordinate systems are disqualified by redshift-magnitud...
1702.04720
Mohd Shahalam
M. Shahalam, S. D. Pathak, Shiyuan Li, R. Myrzakulov, Anzhong Wang
Dynamics of coupled phantom and tachyon fields
16 pages, 6 caption figures, 3 Tables, text, figure are added, matches with the published version
Eur. Phys. J. C (2017) 77:686
10.1140/epjc/s10052-017-5255-1
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we apply the dynamical analysis to a coupled phantom field with scaling potential taking particular forms of the coupling (linear and combination of linear), and present phase space analysis. We investigate if there exist late time accelerated scaling attractor that has the ratio of dark energy and dar...
[ { "created": "Wed, 15 Feb 2017 17:17:13 GMT", "version": "v1" }, { "created": "Fri, 24 Feb 2017 07:16:46 GMT", "version": "v2" }, { "created": "Mon, 23 Oct 2017 09:40:15 GMT", "version": "v3" } ]
2017-10-24
[ [ "Shahalam", "M.", "" ], [ "Pathak", "S. D.", "" ], [ "Li", "Shiyuan", "" ], [ "Myrzakulov", "R.", "" ], [ "Wang", "Anzhong", "" ] ]
In this paper, we apply the dynamical analysis to a coupled phantom field with scaling potential taking particular forms of the coupling (linear and combination of linear), and present phase space analysis. We investigate if there exist late time accelerated scaling attractor that has the ratio of dark energy and dark ...
2211.03497
Breno Giacchini
Luca Buoninfante, Breno L. Giacchini and Tib\'erio de Paula Netto
Black holes in non-local gravity
Invited chapter for the Section "Nonlocal Quantum Gravity" of the "Handbook of Quantum Gravity" (Eds. C. Bambi, L. Modesto and I.L. Shapiro, Springer Singapore, expected in 2023). 29 pages
null
null
NORDITA 2022-076
gr-qc hep-th
http://creativecommons.org/licenses/by/4.0/
In this chapter we present a status report of black hole-like solutions in non-local theories of gravity in which the Lagrangians are at least quadratic in curvature and contain specific non-polynomial (i.e., non-local) operators. In the absence of exact black hole solutions valid in the whole spacetime, most of the ...
[ { "created": "Mon, 7 Nov 2022 12:39:25 GMT", "version": "v1" } ]
2022-11-08
[ [ "Buoninfante", "Luca", "" ], [ "Giacchini", "Breno L.", "" ], [ "Netto", "Tibério de Paula", "" ] ]
In this chapter we present a status report of black hole-like solutions in non-local theories of gravity in which the Lagrangians are at least quadratic in curvature and contain specific non-polynomial (i.e., non-local) operators. In the absence of exact black hole solutions valid in the whole spacetime, most of the li...
1512.02836
Carlos Eduardo Cede\~no Monta\~na
C. E. Cede\~no M. and J. C. N. de Araujo
Master equation solutions in the linear regime of characteristic formulation of general relativity
19 pages
Phys. Rev. D 92, 124015 (2015)
10.1103/PhysRevD.92.124015
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
From the field equations in the linear regime of the characteristic formulation of general relativity, Bishop, for a Schwarzschild's background, and M\"adler, for a Minkowski's background, were able to show that it is possible to derive a fourth order ordinary differential equation, called master equation, for the $J...
[ { "created": "Wed, 9 Dec 2015 12:36:56 GMT", "version": "v1" } ]
2015-12-10
[ [ "M.", "C. E. Cedeño", "" ], [ "de Araujo", "J. C. N.", "" ] ]
From the field equations in the linear regime of the characteristic formulation of general relativity, Bishop, for a Schwarzschild's background, and M\"adler, for a Minkowski's background, were able to show that it is possible to derive a fourth order ordinary differential equation, called master equation, for the $J$ ...
2104.11996
Cristian Quinzacara
Fernando G\'omez, Samuel Lepe, Cristian Quinzacara and Patricio Salgado
Five-dimensional Einstein-Chern-Simons cosmology
14 pages, 2 figures
Phys. Rev. D 103, 104058 (2021)
10.1103/PhysRevD.103.104058
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
We consider a five-dimensional Einstein-Chern-Simons action which is composed of a gravitational sector and a sector of matter, where the gravitational sector is given by a Chern-Simons gravity action instead of the Einstein-Hilbert action, and where the matter sector is given by a perfect fluid. The gravitational la...
[ { "created": "Sat, 24 Apr 2021 18:31:53 GMT", "version": "v1" } ]
2021-05-28
[ [ "Gómez", "Fernando", "" ], [ "Lepe", "Samuel", "" ], [ "Quinzacara", "Cristian", "" ], [ "Salgado", "Patricio", "" ] ]
We consider a five-dimensional Einstein-Chern-Simons action which is composed of a gravitational sector and a sector of matter, where the gravitational sector is given by a Chern-Simons gravity action instead of the Einstein-Hilbert action, and where the matter sector is given by a perfect fluid. The gravitational lagr...
gr-qc/0608002
Larry Ford
Chun-Hsien Wu, Kin-Wang Ng, and L.H. Ford
Possible Constraints on the Duration of Inflationary Expansion from Quantum Stress Tensor Fluctuations
21 pages, no figures; Sect. IV rewritten and expanded, several comments and references added
Phys.Rev.D75:103502,2007
10.1103/PhysRevD.75.103502
null
gr-qc astro-ph hep-th
null
We discuss the effect of quantum stress tensor fluctuations in deSitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in deSitter spacetime, and find that this effect tends to grow, in contrast to the situation in...
[ { "created": "Mon, 31 Jul 2006 21:57:00 GMT", "version": "v1" }, { "created": "Fri, 27 Apr 2007 00:59:30 GMT", "version": "v2" } ]
2008-11-26
[ [ "Wu", "Chun-Hsien", "" ], [ "Ng", "Kin-Wang", "" ], [ "Ford", "L. H.", "" ] ]
We discuss the effect of quantum stress tensor fluctuations in deSitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in deSitter spacetime, and find that this effect tends to grow, in contrast to the situation in f...
1601.05932
Ettore Minguzzi
E. Minguzzi
On the existence of smooth Cauchy steep time functions
Latex2e, 4 pages
Classical and Quantum Gravity 33 (2016) 115001
10.1088/0264-9381/33/11/115001
null
gr-qc math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A simple proof is given that every globally hyperbolic spacetime admits a smooth Cauchy steep time function. This result is useful in order to show that globally hyperbolic spacetimes can be isometrically embedded in Minkowski spacetimes and that they spit as a product. The proof is based on a recent result on the di...
[ { "created": "Fri, 22 Jan 2016 09:57:16 GMT", "version": "v1" } ]
2016-04-28
[ [ "Minguzzi", "E.", "" ] ]
A simple proof is given that every globally hyperbolic spacetime admits a smooth Cauchy steep time function. This result is useful in order to show that globally hyperbolic spacetimes can be isometrically embedded in Minkowski spacetimes and that they spit as a product. The proof is based on a recent result on the diff...
1408.1896
Pierre-Andr\'e Mandrin Ph.D.
Pierre-Andr\'e Mandrin
Spin-compatible construction of a consistent quantum gravity model from minimum information
9 pages, detailed information in relation to the poster presented at the Symposium "Frontiers of Fundamental Physic" in July 2014. v2: "Tetrad bath" instead of "stress bath"; cleaner notation of boundary integrals; use of Gauss' law and S properly decomposed into generalised Palatini + torsion terms
null
null
null
gr-qc hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This article shows in detail the computations made for the poster presented at the Symposium "Frontiers of Fundamental Physics" in July 2014. As was shown in a previous publication, a quantum gravity formulation exists on the basis of abstract quantum number conservation, the laws of thermodynamics, unspecific intera...
[ { "created": "Fri, 8 Aug 2014 16:03:09 GMT", "version": "v1" }, { "created": "Tue, 30 Dec 2014 21:37:40 GMT", "version": "v2" } ]
2015-01-05
[ [ "Mandrin", "Pierre-André", "" ] ]
This article shows in detail the computations made for the poster presented at the Symposium "Frontiers of Fundamental Physics" in July 2014. As was shown in a previous publication, a quantum gravity formulation exists on the basis of abstract quantum number conservation, the laws of thermodynamics, unspecific interact...
gr-qc/0303092
Alicia Herrero
A. Herrero and M. Portilla
Effect of a non null pressure on the evolution of perturbations in the matter dominated epoch
6 figures, you will need some Mathematica fonts to see them correctly
null
null
null
gr-qc
null
We analyze the effect of pressure on the evolution of perturbations of an Einstein-de Sitter Universe in the matter dominated epoch assuming an ideal gas equation of state. For the sake of simplicity the temperature is considered uniform. The goal of the paper is to examine the validity of the linear approximation. W...
[ { "created": "Mon, 24 Mar 2003 12:49:53 GMT", "version": "v1" }, { "created": "Wed, 24 Sep 2003 14:06:44 GMT", "version": "v2" } ]
2007-05-23
[ [ "Herrero", "A.", "" ], [ "Portilla", "M.", "" ] ]
We analyze the effect of pressure on the evolution of perturbations of an Einstein-de Sitter Universe in the matter dominated epoch assuming an ideal gas equation of state. For the sake of simplicity the temperature is considered uniform. The goal of the paper is to examine the validity of the linear approximation. Wit...
1111.5266
Ivana Bochicchio Dr
Ivana Bochicchio and Valerio Faraoni
Cosmological expansion and local systems: a Lema\^{i}tre-Tolman-Bondi model
null
General Relativity and Gravitation, Vol. 44 (2012) pp. 1479-1487
10.1007/s10714-012-1350-7
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a Lema\^{i}tre-Tolman-Bondi system mimicking a two-body system to address the problem of the cosmological expansion versus local dynamics. This system is strongly bound but participates in the cosmic expansion and is exactly comoving with the cosmic substratum.
[ { "created": "Tue, 22 Nov 2011 17:59:27 GMT", "version": "v1" }, { "created": "Tue, 13 Mar 2012 11:00:12 GMT", "version": "v2" }, { "created": "Tue, 8 Jan 2013 13:48:52 GMT", "version": "v3" } ]
2013-01-09
[ [ "Bochicchio", "Ivana", "" ], [ "Faraoni", "Valerio", "" ] ]
We propose a Lema\^{i}tre-Tolman-Bondi system mimicking a two-body system to address the problem of the cosmological expansion versus local dynamics. This system is strongly bound but participates in the cosmic expansion and is exactly comoving with the cosmic substratum.
gr-qc/0204059
Peter Dunsby
Naureen Goheer and Peter Dunsby
Braneworld Dynamics of Inflationary Cosmologies with Exponential Potentials
15 pages, 9 figures, RevTex 4. Submitted to Physical Review D
Phys.Rev. D66 (2002) 043527
10.1103/PhysRevD.66.043527
null
gr-qc
null
In this work we consider Randall-Sundrum braneworld type scenarios, in which the spacetime is described by a five-dimensional manifold with matter fields confined in a domain wall or three-brane. We present the results of a systematic analysis, using dynamical systems techniques, of the qualitative behaviour of Fried...
[ { "created": "Thu, 18 Apr 2002 05:29:35 GMT", "version": "v1" } ]
2009-11-07
[ [ "Goheer", "Naureen", "" ], [ "Dunsby", "Peter", "" ] ]
In this work we consider Randall-Sundrum braneworld type scenarios, in which the spacetime is described by a five-dimensional manifold with matter fields confined in a domain wall or three-brane. We present the results of a systematic analysis, using dynamical systems techniques, of the qualitative behaviour of Friedma...
gr-qc/0606053
Oliver Rinne
Oliver Rinne
Stable radiation-controlling boundary conditions for the generalized harmonic Einstein equations
27 pages, 4 figures; more numerical results and references added, several minor amendments; version accepted for publication in Class. Quantum Grav
Class. Quantum Grav. 23, 6275-6300 (2006)
10.1088/0264-9381/23/22/013
null
gr-qc
null
This paper is concerned with the initial-boundary value problem for the Einstein equations in a first-order generalized harmonic formulation. We impose boundary conditions that preserve the constraints and control the incoming gravitational radiation by prescribing data for the incoming fields of the Weyl tensor. Hig...
[ { "created": "Mon, 12 Jun 2006 19:01:56 GMT", "version": "v1" }, { "created": "Wed, 6 Sep 2006 20:13:32 GMT", "version": "v2" } ]
2008-11-22
[ [ "Rinne", "Oliver", "" ] ]
This paper is concerned with the initial-boundary value problem for the Einstein equations in a first-order generalized harmonic formulation. We impose boundary conditions that preserve the constraints and control the incoming gravitational radiation by prescribing data for the incoming fields of the Weyl tensor. High-...
2402.18750
Peter K.F. Kuhfittig
Peter K.F. Kuhfittig
Wormholes supported by small extra dimensions
7 pages, no figures
Adv. Studies Theor. Phys., vol. 18, no.1, pp. 41-48, 2024
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Holding a Morris-Thorne wormhole open requires a violation of the null energy condition, calling for the need for so-called exotic matter near the throat. Many researchers consider exotic matter to be completely unphysical in classical general relativity. It has been shown, however, that the existence of an extra mac...
[ { "created": "Wed, 28 Feb 2024 23:11:22 GMT", "version": "v1" } ]
2024-03-01
[ [ "Kuhfittig", "Peter K. F.", "" ] ]
Holding a Morris-Thorne wormhole open requires a violation of the null energy condition, calling for the need for so-called exotic matter near the throat. Many researchers consider exotic matter to be completely unphysical in classical general relativity. It has been shown, however, that the existence of an extra macro...
2102.08339
Massimiliano Maria Riva
Stavros Mougiakakos, Massimiliano Maria Riva and Filippo Vernizzi
Gravitational Bremsstrahlung in the Post-Minkowskian Effective Field Theory
11 pages, 1 figure
Phys. Rev. D 104, 024041 (2021)
10.1103/PhysRevD.104.024041
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the gravitational radiation emitted during the scattering of two spinless bodies in the post-Minkowskian Effective Field Theory approach. We derive the conserved stress-energy tensor linearly coupled to gravity and the classical probability amplitude of graviton emission at leading and next-to-leading order ...
[ { "created": "Tue, 16 Feb 2021 18:24:44 GMT", "version": "v1" }, { "created": "Fri, 25 Jun 2021 15:58:36 GMT", "version": "v2" } ]
2021-07-21
[ [ "Mougiakakos", "Stavros", "" ], [ "Riva", "Massimiliano Maria", "" ], [ "Vernizzi", "Filippo", "" ] ]
We study the gravitational radiation emitted during the scattering of two spinless bodies in the post-Minkowskian Effective Field Theory approach. We derive the conserved stress-energy tensor linearly coupled to gravity and the classical probability amplitude of graviton emission at leading and next-to-leading order in...
0803.3399
Tomi Koivisto
Tomi Koivisto
Dynamics of Nonlocal Cosmology
14 pages, 3 figures. V2: minor corrections
Phys.Rev.D77:123513,2008
10.1103/PhysRevD.77.123513
null
gr-qc astro-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Nonlocal quantum corrections to gravity have been recently proposed as a possible solution to the cosmological fine tuning problems. We study the dynamics of a class of nonlocal actions defined by a function of the inverse d'Alembertian of the Ricci scalar. Power-law and expnential functions are considered in detail,...
[ { "created": "Mon, 24 Mar 2008 12:50:16 GMT", "version": "v1" }, { "created": "Fri, 6 Jun 2008 09:33:08 GMT", "version": "v2" } ]
2008-11-26
[ [ "Koivisto", "Tomi", "" ] ]
Nonlocal quantum corrections to gravity have been recently proposed as a possible solution to the cosmological fine tuning problems. We study the dynamics of a class of nonlocal actions defined by a function of the inverse d'Alembertian of the Ricci scalar. Power-law and expnential functions are considered in detail, b...
1705.09633
Yen Chin Ong
Zi-Yu Tang, Yen Chin Ong, Bin Wang
Lux in obscuro II: Photon Orbits of Extremal AdS Black Holes Revisited
23 pages, 8 figures. Fixed some typos. Version accepted by CQG
null
10.1088/1361-6382/aa95ff
null
gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A large class of spherically symmetric static extremal black hole spacetimes possesses a stable null photon sphere on their horizons. For the extremal Kerr-Newman family, the photon sphere only really coincides with the horizon in the sense clarified by Doran. The condition under which photon orbit is stable on an as...
[ { "created": "Fri, 26 May 2017 16:09:24 GMT", "version": "v1" }, { "created": "Mon, 14 Aug 2017 16:52:04 GMT", "version": "v2" }, { "created": "Fri, 3 Nov 2017 09:51:22 GMT", "version": "v3" } ]
2017-11-06
[ [ "Tang", "Zi-Yu", "" ], [ "Ong", "Yen Chin", "" ], [ "Wang", "Bin", "" ] ]
A large class of spherically symmetric static extremal black hole spacetimes possesses a stable null photon sphere on their horizons. For the extremal Kerr-Newman family, the photon sphere only really coincides with the horizon in the sense clarified by Doran. The condition under which photon orbit is stable on an asym...
2401.14643
Qiaoyin Pan
Muxin Han, Qiaoyin Pan
Deficit Angles in 4D Spinfoam with Cosmological Constant: (Anti) de Sitter-ness and More
a figure corrected
null
null
null
gr-qc hep-th math-ph math.MP
http://creativecommons.org/licenses/by-nc-sa/4.0/
This paper investigates the critical behaviors of the 4-dimensional spinfoam model with cosmological constant for a general 4-dimensional simplicial complex as the discretization of spacetime. We find that, at the semi-classical regime, the spinfoam amplitude is peaked at the real critical points that correspond to z...
[ { "created": "Fri, 26 Jan 2024 04:22:45 GMT", "version": "v1" }, { "created": "Wed, 14 Feb 2024 03:35:19 GMT", "version": "v2" } ]
2024-02-15
[ [ "Han", "Muxin", "" ], [ "Pan", "Qiaoyin", "" ] ]
This paper investigates the critical behaviors of the 4-dimensional spinfoam model with cosmological constant for a general 4-dimensional simplicial complex as the discretization of spacetime. We find that, at the semi-classical regime, the spinfoam amplitude is peaked at the real critical points that correspond to zer...
1311.4661
Titus K Mathew
Titus K Mathew and P. Praseetha
Holographic Ricci dark energy and generalized second law
null
Mod.Phys.Lett. A29 (2014) no.06, 1450023
10.1142/S0217732314500230
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the validity of the generalized second law (GSL) of thermodynamics in flat FRW universe with apparent horizon and event horizon as the boundary. We found that in a universe with holographic Ricci dark energy and dark matter, interacting with each other, the GSL is satisfied at the apparent horizon and part...
[ { "created": "Tue, 19 Nov 2013 09:12:14 GMT", "version": "v1" }, { "created": "Wed, 20 Nov 2013 09:02:24 GMT", "version": "v2" } ]
2019-05-13
[ [ "Mathew", "Titus K", "" ], [ "Praseetha", "P.", "" ] ]
We explore the validity of the generalized second law (GSL) of thermodynamics in flat FRW universe with apparent horizon and event horizon as the boundary. We found that in a universe with holographic Ricci dark energy and dark matter, interacting with each other, the GSL is satisfied at the apparent horizon and partia...
2304.03261
Ahmad Sheykhi
A. Sheykhi and S. Ghaffari
Note on agegraphic dark energy inspired by modified Barrow entropy
11 pages
Physics of the Dark Universe 41 (2023) 101241
10.1016/j.dark.2023.101241
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
We revisit agegraphic dark energy (ADE) model when the entropy associated with the apparent horizon is in the form of Barrow entropy, $S\sim A^{1+\delta/2}$, where $0\leq\delta\leq1$ indicates the amount of the quantum-gravitational deformation effects of the horizon. The modification to the entropy expression, not o...
[ { "created": "Thu, 6 Apr 2023 17:47:12 GMT", "version": "v1" } ]
2023-05-18
[ [ "Sheykhi", "A.", "" ], [ "Ghaffari", "S.", "" ] ]
We revisit agegraphic dark energy (ADE) model when the entropy associated with the apparent horizon is in the form of Barrow entropy, $S\sim A^{1+\delta/2}$, where $0\leq\delta\leq1$ indicates the amount of the quantum-gravitational deformation effects of the horizon. The modification to the entropy expression, not onl...
1906.08583
Abbas Sherif
Abbas Sherif, Rituparno Goswami, Sunil D. Maharaj
On Properties of Expansion-free Dynamical Stars
6 pages
Phys. Rev. D 100, 044039 (2019)
10.1103/PhysRevD.100.044039
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the geometrical and dynamical features of expansion-free dynamical stars in general relativity. Such stars can exist only if particular physical and geometric conditions are satisfied. Firstly, for trapping to exist in an expansion-free dynamical star, the star must accelerate and radiate simultaneously. If ...
[ { "created": "Thu, 20 Jun 2019 12:49:16 GMT", "version": "v1" }, { "created": "Sun, 25 Aug 2019 23:22:44 GMT", "version": "v2" } ]
2019-08-28
[ [ "Sherif", "Abbas", "" ], [ "Goswami", "Rituparno", "" ], [ "Maharaj", "Sunil D.", "" ] ]
We study the geometrical and dynamical features of expansion-free dynamical stars in general relativity. Such stars can exist only if particular physical and geometric conditions are satisfied. Firstly, for trapping to exist in an expansion-free dynamical star, the star must accelerate and radiate simultaneously. If ei...
gr-qc/9503060
Bernard Linet
B. Linet
Vacuum polarization induced by a uniformly accelerated charge
13 pages, latex, no figures, to appear in Int. J. Theor. Phys.
Int.J.Theor.Phys. 34 (1995) 1055-1064
10.1007/BF00671366
GCR-941003
gr-qc
null
We consider a point charge fixed in the Rindler coordinates which describe a uniformly accelerated frame. We determine an integral expression of the induced charge density due to the vacuum polarization at the first order in the fine structure constant. In the case where the acceleration is weak, we give explicitly t...
[ { "created": "Thu, 30 Mar 1995 12:55:07 GMT", "version": "v1" } ]
2009-10-28
[ [ "Linet", "B.", "" ] ]
We consider a point charge fixed in the Rindler coordinates which describe a uniformly accelerated frame. We determine an integral expression of the induced charge density due to the vacuum polarization at the first order in the fine structure constant. In the case where the acceleration is weak, we give explicitly the...
gr-qc/0610059
John W. Moffat
J. W. Moffat
Non-Singular Cosmology in Modified Gravity
10 pages, no figures, Latex file. Revised version of paper
null
null
null
gr-qc
null
A non-singular cosmology is derived in modified gravity (MOG) with a varying gravitational coupling strength $G(t)=G_N\xi(t)$. Assuming that the curvature $k$, the cosmological constant $\Lambda$ and $\rho$ vanish at $t=0$, we obtain a non-singular universe with a negative pressure, $p_G < 0$. Quantum fluctuations at...
[ { "created": "Wed, 11 Oct 2006 22:09:19 GMT", "version": "v1" }, { "created": "Fri, 16 Feb 2007 19:11:00 GMT", "version": "v2" }, { "created": "Wed, 24 Oct 2007 18:38:49 GMT", "version": "v3" } ]
2007-10-24
[ [ "Moffat", "J. W.", "" ] ]
A non-singular cosmology is derived in modified gravity (MOG) with a varying gravitational coupling strength $G(t)=G_N\xi(t)$. Assuming that the curvature $k$, the cosmological constant $\Lambda$ and $\rho$ vanish at $t=0$, we obtain a non-singular universe with a negative pressure, $p_G < 0$. Quantum fluctuations at $...
1206.3689
Lorenzo Fatibene
L. Fatibene, M. Francaviglia, S.Garruto
Do Barbero-Immirzi connections exist in different dimensions and signatures?
8 pages
null
null
null
gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We shall show that no reductive splitting of the spin group exists in dimension 3 \leq m \leq 20 other than in dimension m = 4. In dimension 4 there are reductive splittings in any signature. Euclidean and Lorentzian signatures are reviewed in particular and signature (2, 2) is investigated explicitly in detail. Redu...
[ { "created": "Sat, 16 Jun 2012 18:44:21 GMT", "version": "v1" } ]
2012-06-19
[ [ "Fatibene", "L.", "" ], [ "Francaviglia", "M.", "" ], [ "Garruto", "S.", "" ] ]
We shall show that no reductive splitting of the spin group exists in dimension 3 \leq m \leq 20 other than in dimension m = 4. In dimension 4 there are reductive splittings in any signature. Euclidean and Lorentzian signatures are reviewed in particular and signature (2, 2) is investigated explicitly in detail. Reduct...
gr-qc/9901081
N. K. Dadhich
Naresh Dadhich and A.K. Raychaudhuri
Oscillating non-singular relativistic spherical model
6 pages, REVTEX version
Mod.Phys.Lett. A14 (1999) 2135-2138
10.1142/S0217732399002194
IUCAA-5/99
gr-qc
null
A particular choice of the time function in the recently presented spherical solution by Dadhich [1] leads to a singularity free cosmological model which oscillates between two regular states. The energy-stress tensor involves anisotropic pressure and a heat flux term but is consistent with the usual energy condition...
[ { "created": "Thu, 28 Jan 1999 09:11:16 GMT", "version": "v1" } ]
2009-10-31
[ [ "Dadhich", "Naresh", "" ], [ "Raychaudhuri", "A. K.", "" ] ]
A particular choice of the time function in the recently presented spherical solution by Dadhich [1] leads to a singularity free cosmological model which oscillates between two regular states. The energy-stress tensor involves anisotropic pressure and a heat flux term but is consistent with the usual energy conditions ...
2308.01812
Daniela Cors
Daniela Cors, Sarah Renkhoff, Hannes R. R\"uter, David Hilditch and Bernd Br\"ugmann
Formulation Improvements for Critical Collapse Simulations
19 pages, 10 figures
null
null
null
gr-qc
http://creativecommons.org/licenses/by/4.0/
The precise tuning required to observe critical phenomena in gravitational collapse poses a challenge for most numerical codes. First, threshold estimation searches may be obstructed by the appearance of coordinate singularities, indicating the need for a better gauge choice. Second, the constraint violations to whic...
[ { "created": "Thu, 3 Aug 2023 15:17:42 GMT", "version": "v1" } ]
2023-08-04
[ [ "Cors", "Daniela", "" ], [ "Renkhoff", "Sarah", "" ], [ "Rüter", "Hannes R.", "" ], [ "Hilditch", "David", "" ], [ "Brügmann", "Bernd", "" ] ]
The precise tuning required to observe critical phenomena in gravitational collapse poses a challenge for most numerical codes. First, threshold estimation searches may be obstructed by the appearance of coordinate singularities, indicating the need for a better gauge choice. Second, the constraint violations to which ...