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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1911.05848 | Dmitry Chirkov | Dmitry Chirkov, Alex Giacomini, Alexey Toporensky | Anisotropic cosmological dynamics in Einstein-Gauss-Bonnet gravity: an
example of dynamical compactification in 7+1 dimensions | 11 pages, 3 figures | Gen. Rel. Grav. 52:30 (2020) | 10.1007/s10714-020-02679-x | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a particular example of dynamical compactification of an
anisotropic 7+1 dimensional Universe in Einstein - Gauss - Bonnet gravity.
Starting from rather general totally anisotropic initial conditions a Universe
in question evolves towards a product of two isotropic subspaces. The first
subspace expands is... | [
{
"created": "Wed, 13 Nov 2019 22:45:32 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Nov 2019 22:38:03 GMT",
"version": "v2"
},
{
"created": "Wed, 1 Apr 2020 14:19:57 GMT",
"version": "v3"
}
] | 2020-04-02 | [
[
"Chirkov",
"Dmitry",
""
],
[
"Giacomini",
"Alex",
""
],
[
"Toporensky",
"Alexey",
""
]
] | We consider a particular example of dynamical compactification of an anisotropic 7+1 dimensional Universe in Einstein - Gauss - Bonnet gravity. Starting from rather general totally anisotropic initial conditions a Universe in question evolves towards a product of two isotropic subspaces. The first subspace expands isot... |
1203.1702 | Manfred Requardt | Manfred Requardt | Gravitons as Goldstone Modes and the Spontaneous Symmetry Breaking of
Diffeomorphism Invariance | 19 pages, Latex | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We complement investigations of the gauge structure of general relativity
with an analysis of the physical consequences of the spontaneous breaking of
diffeomorphism invariance which manifests itself in e.g. the socalled Einstein
hole problem. We analyze the nature of the gravitons as Goldstone excitations
both in th... | [
{
"created": "Thu, 8 Mar 2012 08:11:48 GMT",
"version": "v1"
}
] | 2012-03-09 | [
[
"Requardt",
"Manfred",
""
]
] | We complement investigations of the gauge structure of general relativity with an analysis of the physical consequences of the spontaneous breaking of diffeomorphism invariance which manifests itself in e.g. the socalled Einstein hole problem. We analyze the nature of the gravitons as Goldstone excitations both in the ... |
1107.0854 | Ioannis Kamaretsos | Ioannis Kamaretsos (Cardiff), Mark Hannam (Cardiff), Sascha Husa
(Palma), and B. S. Sathyaprakash (Cardiff) | Black-hole hair loss: learning about binary progenitors from ringdown
signals | 24 pages, 9 figures, 4 tables, accepted for publication in Physical
Review D | null | 10.1103/PhysRevD.85.024018 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Perturbed Kerr black holes emit gravitational radiation, which (for the
practical purposes of gravitational-wave astronomy) consists of a superposition
of damped sinusoids termed quasi-normal modes. The frequencies and
time-constants of the modes depend only on the mass and spin of the black hole
- a consequence of t... | [
{
"created": "Tue, 5 Jul 2011 12:10:38 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Oct 2011 14:24:53 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Jan 2012 19:17:46 GMT",
"version": "v3"
}
] | 2013-05-30 | [
[
"Kamaretsos",
"Ioannis",
"",
"Cardiff"
],
[
"Hannam",
"Mark",
"",
"Cardiff"
],
[
"Husa",
"Sascha",
"",
"Palma"
],
[
"Sathyaprakash",
"B. S.",
"",
"Cardiff"
]
] | Perturbed Kerr black holes emit gravitational radiation, which (for the practical purposes of gravitational-wave astronomy) consists of a superposition of damped sinusoids termed quasi-normal modes. The frequencies and time-constants of the modes depend only on the mass and spin of the black hole - a consequence of the... |
1311.6786 | J\"org Hennig | J\"org Frauendiener and J\"org Hennig | Fully pseudospectral solution of the conformally invariant wave equation
near the cylinder at spacelike infinity | 16 pages, 6 figures | Class. Quantum Grav. 31, 085010 (2014) | 10.1088/0264-9381/31/8/085010 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the scalar, conformally invariant wave equation on a
four-dimensional Minkowski background in spherical symmetry, using a fully
pseudospectral numerical scheme. Thereby, our main interest is in a suitable
treatment of spatial infinity, which is represented as a cylinder. We consider
both Cauchy problems, whe... | [
{
"created": "Tue, 26 Nov 2013 19:41:41 GMT",
"version": "v1"
},
{
"created": "Wed, 2 Apr 2014 01:05:39 GMT",
"version": "v2"
}
] | 2014-04-03 | [
[
"Frauendiener",
"Jörg",
""
],
[
"Hennig",
"Jörg",
""
]
] | We study the scalar, conformally invariant wave equation on a four-dimensional Minkowski background in spherical symmetry, using a fully pseudospectral numerical scheme. Thereby, our main interest is in a suitable treatment of spatial infinity, which is represented as a cylinder. We consider both Cauchy problems, where... |
gr-qc/0602081 | Tiberiu Harko | C. G. Boehmer, T. Harko | Physics of dark energy particles | 10 pages, no figures; typos corrected, 4 references added; 1
reference added; reference added; entirely revised version, contains new
parts, now 14 pages | Found.Phys.38:216,2008 | 10.1007/s10701-007-9199-4 | null | gr-qc astro-ph hep-th | null | We consider the astrophysical and cosmological implications of the existence
of a minimum density and mass due to the presence of the cosmological constant.
If there is a minimum length in nature, then there is an absolute minimum mass
corresponding to a hypothetical particle with radius of the order of the Planck
le... | [
{
"created": "Tue, 21 Feb 2006 02:01:32 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Feb 2006 02:28:13 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Apr 2006 02:36:59 GMT",
"version": "v3"
},
{
"created": "Thu, 1 Jun 2006 19:41:33 GMT",
"version": "v4"
},
{
"cr... | 2008-11-26 | [
[
"Boehmer",
"C. G.",
""
],
[
"Harko",
"T.",
""
]
] | We consider the astrophysical and cosmological implications of the existence of a minimum density and mass due to the presence of the cosmological constant. If there is a minimum length in nature, then there is an absolute minimum mass corresponding to a hypothetical particle with radius of the order of the Planck leng... |
2301.07973 | \'Alvaro Mozota Frauca | Alvaro Mozota Frauca | Reassessing the problem of time of quantum gravity | To be published in General Relativity and Gravitation | Gen. Relativ. Gravit. 55, 21 (2023) | 10.1007/s10714-023-03067-x | null | gr-qc physics.hist-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper I raise a worry about the most extended resolutions of the
problem of time of canonical quantizations of general relativity. The reason
for this is that these resolutions are based on analogies with deparametrizable
models for which the problem can be solved, while I argue in this paper that
there are g... | [
{
"created": "Thu, 19 Jan 2023 10:02:53 GMT",
"version": "v1"
}
] | 2023-01-26 | [
[
"Frauca",
"Alvaro Mozota",
""
]
] | In this paper I raise a worry about the most extended resolutions of the problem of time of canonical quantizations of general relativity. The reason for this is that these resolutions are based on analogies with deparametrizable models for which the problem can be solved, while I argue in this paper that there are goo... |
2308.03947 | Ali \"Ovg\"un Dr. | \.Ilim \.Irfan \c{C}imdiker, Ali \"Ovg\"un and Durmu\c{s} Demir | Thin accretion disk images of the black hole in symmergent gravity | 30 pages. Accepted for publication in Classical and Quantum Gravity,
"Special Issue: Focus on Quantum Gravity Phenomenology in the Multi-Messenger
Era: Challenges and Perspectives"
(https://iopscience.iop.org/article/10.1088/1361-6382/aceb45). arXiv admin
note: text overlap with arXiv:1901.05762, arXiv:2002.005... | Class. Quantum Grav. 40 (2023) 184001 | 10.1088/1361-6382/aceb45 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | In this paper, we study circular orbits, effective potential, and
thin-accretion disk of a black hole in symmergent gravity within the
Novikov-Thorne model in a way including the energy flux and temperature
distribution. We determine bounds on symmergent gravity parameters and conclude
that the accretion disk could b... | [
{
"created": "Mon, 7 Aug 2023 23:28:53 GMT",
"version": "v1"
}
] | 2023-08-09 | [
[
"Çimdiker",
"İlim İrfan",
""
],
[
"Övgün",
"Ali",
""
],
[
"Demir",
"Durmuş",
""
]
] | In this paper, we study circular orbits, effective potential, and thin-accretion disk of a black hole in symmergent gravity within the Novikov-Thorne model in a way including the energy flux and temperature distribution. We determine bounds on symmergent gravity parameters and conclude that the accretion disk could be ... |
1311.3836 | Alexandre Le Tiec | Alexandre Le Tiec | A Note on Celestial Mechanics in Kerr Spacetime | 7 pages; matches version to appear in Class. Quant. Grav | Class.Quant.Grav.31:097001,2014 | 10.1088/0264-9381/31/9/097001 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Hamilton-Jacobi equation for test particles in the Kerr geometry is
separable. Using action-angle variables, we establish several relations between
various physical quantities that characterize bound timelike geodesic orbits
around a spinning black hole, including the particle's rest mass, energy,
angular momentu... | [
{
"created": "Fri, 15 Nov 2013 12:55:25 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Mar 2014 14:11:57 GMT",
"version": "v2"
}
] | 2014-04-21 | [
[
"Tiec",
"Alexandre Le",
""
]
] | The Hamilton-Jacobi equation for test particles in the Kerr geometry is separable. Using action-angle variables, we establish several relations between various physical quantities that characterize bound timelike geodesic orbits around a spinning black hole, including the particle's rest mass, energy, angular momentum,... |
1109.6324 | Thomas Sotiriou | Thomas P. Sotiriou, Valerio Faraoni | Black holes in scalar-tensor gravity | v1: 4 pages; v2: typos corrected, published version | Phys. Rev. Lett. 108, 081103 (2012) | 10.1103/PhysRevLett.108.081103 | null | gr-qc astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Hawking has proven that black holes which are stationary as the endpoint of
gravitational collapse in Brans--Dicke theory (without a potential) are no
different than in general relativity. We extend this proof to the much more
general class of scalar-tensor and f(R) gravity theories, without assuming any
symmetries a... | [
{
"created": "Wed, 28 Sep 2011 20:00:03 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Mar 2012 17:31:41 GMT",
"version": "v2"
}
] | 2012-03-07 | [
[
"Sotiriou",
"Thomas P.",
""
],
[
"Faraoni",
"Valerio",
""
]
] | Hawking has proven that black holes which are stationary as the endpoint of gravitational collapse in Brans--Dicke theory (without a potential) are no different than in general relativity. We extend this proof to the much more general class of scalar-tensor and f(R) gravity theories, without assuming any symmetries apa... |
gr-qc/0106067 | Shih-Yuin Lin | Shih-Yuin Lin | Classical Aspects of Accelerated Unruh-DeWitt Type Monopole Detectors | 7 pages; typos and references added, minor correction in Sec.IV | null | null | null | gr-qc hep-th | null | We have shown the classical correspondence of Unruh effect in the classical
relativistic electron theory in our previous work (gr-qc/0105051). Here we
demonstrate the analogy between the classical relativistic electron theory and
the classical Unruh-DeWitt type monopole detector theory. The field
configuration genera... | [
{
"created": "Thu, 21 Jun 2001 11:48:49 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Jun 2001 12:56:48 GMT",
"version": "v2"
},
{
"created": "Sun, 8 Jul 2001 09:49:31 GMT",
"version": "v3"
}
] | 2007-05-23 | [
[
"Lin",
"Shih-Yuin",
""
]
] | We have shown the classical correspondence of Unruh effect in the classical relativistic electron theory in our previous work (gr-qc/0105051). Here we demonstrate the analogy between the classical relativistic electron theory and the classical Unruh-DeWitt type monopole detector theory. The field configuration generate... |
gr-qc/0608070 | Dr. Anirudh Pradhan | A. Pradhan, J. P. Shahi and C. B. Singh | Cosmological Models of Universe with Variable Deceleration Parameter in
Lyra's Manifold | 11 pages, 3 figures. To appear in Braz. J. Phys | Braz.J.Phys. 36 (2006) 1227-1231 | 10.1590/S0103-97332006000700020 | null | gr-qc | null | FRW models of the universe have been studied in the cosmological theory based
on Lyra's manifold. A new class of exact solutions has been obtained by
considering a time dependent displacement field for variable deceleration
parameter from which three models of the universe are derived (i) exponential
(ii) polynomial ... | [
{
"created": "Mon, 14 Aug 2006 11:23:26 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Nov 2006 08:14:18 GMT",
"version": "v2"
}
] | 2015-06-25 | [
[
"Pradhan",
"A.",
""
],
[
"Shahi",
"J. P.",
""
],
[
"Singh",
"C. B.",
""
]
] | FRW models of the universe have been studied in the cosmological theory based on Lyra's manifold. A new class of exact solutions has been obtained by considering a time dependent displacement field for variable deceleration parameter from which three models of the universe are derived (i) exponential (ii) polynomial an... |
0912.1823 | Sabine Hossenfelder | Sabine Hossenfelder, Leonardo Modesto, Isabeau Pr\'emont-Schwarz | A model for non-singular black hole collapse and evaporation | 7 pages, 3 figures, references added, replaced with published version | Phys.Rev.D81:044036,2010 | 10.1103/PhysRevD.81.044036 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the formation of a black hole and its subsequent evaporation in a
model employing a minisuperspace approach to loop quantum gravity. In previous
work the static solution was obtained and shown to be singularity-free. Here,
we examine the more realistic dynamical case by generalizing the static case
with help... | [
{
"created": "Wed, 9 Dec 2009 18:16:54 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Dec 2009 12:05:54 GMT",
"version": "v2"
},
{
"created": "Wed, 24 Feb 2010 17:17:25 GMT",
"version": "v3"
}
] | 2010-04-21 | [
[
"Hossenfelder",
"Sabine",
""
],
[
"Modesto",
"Leonardo",
""
],
[
"Prémont-Schwarz",
"Isabeau",
""
]
] | We study the formation of a black hole and its subsequent evaporation in a model employing a minisuperspace approach to loop quantum gravity. In previous work the static solution was obtained and shown to be singularity-free. Here, we examine the more realistic dynamical case by generalizing the static case with help o... |
gr-qc/9901002 | Aharon Davidson | Aharon Davidson and David Karasik | Cosmic Solenoids: Minimal Cross-Section and Generalized Flux
Quantization | Revtex, 11 twocolumn pages, 3 eps figures (accepted for publication
in Phys. Rev. D) | Phys.Rev. D60 (1999) 045002 | 10.1103/PhysRevD.60.045002 | null | gr-qc astro-ph hep-th | null | A self-consistent general relativistic configuration describing a finite
cross-section magnetic flux tube is constructed. The cosmic solenoid is modeled
by an elastic superconductive surface which separates the Melvin core from the
surrounding flat conic structure. We show that a given amount $\Phi$ of
magnetic flux ... | [
{
"created": "Sat, 2 Jan 1999 10:21:26 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Davidson",
"Aharon",
""
],
[
"Karasik",
"David",
""
]
] | A self-consistent general relativistic configuration describing a finite cross-section magnetic flux tube is constructed. The cosmic solenoid is modeled by an elastic superconductive surface which separates the Melvin core from the surrounding flat conic structure. We show that a given amount $\Phi$ of magnetic flux ca... |
1105.0328 | Gamal G.L. Nashed | Gamal G.L. Nashed | Energy and momentum of a spherically symmetric dilaton frame as
regularized by teleparallel gravity | 11 Pages Latex, Accepted for publication in Annalen der Physik | Ann. Phys. (Berlin) 523, No. 6, 450 -- 458 (2011) | 10.1002/andp.201100030 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate energy and momentum of a spherically symmetric dilaton frame
using the gravitational energy-momentum 3-form within the tetrad formulation of
general relativity (GR). The frame we use is characterized by an arbitrary
function $\Upsilon$ with the help of which all the previously found solutions
can be repr... | [
{
"created": "Thu, 28 Apr 2011 10:29:55 GMT",
"version": "v1"
}
] | 2011-05-25 | [
[
"Nashed",
"Gamal G. L.",
""
]
] | We calculate energy and momentum of a spherically symmetric dilaton frame using the gravitational energy-momentum 3-form within the tetrad formulation of general relativity (GR). The frame we use is characterized by an arbitrary function $\Upsilon$ with the help of which all the previously found solutions can be reprod... |
1802.00365 | Burkhard Kleihaus | Xiao Yan Chew, Burkhard Kleihaus, and Jutta Kunz (University of
Oldenburg) | Spinning Wormholes in Scalar-Tensor Theory | null | Phys. Rev. D 97, 064026 (2018) | 10.1103/PhysRevD.97.064026 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider spinning generalizations of the Ellis wormhole in scalar-tensor
theory. Analogous to other compact objects these wormholes can carry a
non-trivial scalarization. We determine the domain of existence of the
scalarized wormholes and investigate the effect of the scalarization on their
properties. Depending ... | [
{
"created": "Thu, 1 Feb 2018 15:58:37 GMT",
"version": "v1"
}
] | 2018-03-28 | [
[
"Chew",
"Xiao Yan",
"",
"University of\n Oldenburg"
],
[
"Kleihaus",
"Burkhard",
"",
"University of\n Oldenburg"
],
[
"Kunz",
"Jutta",
"",
"University of\n Oldenburg"
]
] | We consider spinning generalizations of the Ellis wormhole in scalar-tensor theory. Analogous to other compact objects these wormholes can carry a non-trivial scalarization. We determine the domain of existence of the scalarized wormholes and investigate the effect of the scalarization on their properties. Depending on... |
1511.00627 | Shao-Jiang Wang | Rong-Gen Cai, Shao-Jiang Wang | Dark matter superfluid and DBI dark energy | v1, 4 pages, no figure; v2, 8 pages, 4 figures, numerical
justifications added; v3, references added, final version to match the
published version | Phys. Rev. D 93, 023515 (2016) | 10.1103/PhysRevD.93.023515 | null | gr-qc astro-ph.CO hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It was shown recently that, without jeopardizing the success of the $\Lambda$
cold dark matter model on cosmic scales, the modified Newtonian dynamics (MOND)
can be derived as an emergent phenomenon when axionlike dark matter particles
condense into superfluid on the galactic scales. We propose in this paper a
Dirac-... | [
{
"created": "Sun, 25 Oct 2015 13:13:15 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Dec 2015 14:07:39 GMT",
"version": "v2"
},
{
"created": "Sat, 23 Jan 2016 01:59:19 GMT",
"version": "v3"
}
] | 2016-01-26 | [
[
"Cai",
"Rong-Gen",
""
],
[
"Wang",
"Shao-Jiang",
""
]
] | It was shown recently that, without jeopardizing the success of the $\Lambda$ cold dark matter model on cosmic scales, the modified Newtonian dynamics (MOND) can be derived as an emergent phenomenon when axionlike dark matter particles condense into superfluid on the galactic scales. We propose in this paper a Dirac-Bo... |
0810.1491 | Alberto Lobo | P Canizares, A Conchillo, E Garcia-Berro, L Gesa, C Grimani, I Lloro,
A Lobo, I Mateos, M Nofrarias, J Ramos-Castro, J Sanjuan and CF Sopuerta | The diagnostics subsystem on board LISA PathFinder and LISA | 11 pages, 5 figures, pdflatex, prepared for the Proceedings of the
7th International LISA Symposium (Barcelona, Spain, 16-20 June-2008),
submitted to Classical and Quantum Gravity | null | 10.1088/0264-9381/26/9/094005 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Data and Diagnostics Subsystem of the LTP hardware and software are at
present essentially ready for delivery. In this presentation we intend to
describe the scientific and technical aspects of this subsystem, which includes
thermal diagnostics, magnetic diagnostics and a Radiation Monitor, as well as
the prospec... | [
{
"created": "Wed, 8 Oct 2008 17:33:03 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Canizares",
"P",
""
],
[
"Conchillo",
"A",
""
],
[
"Garcia-Berro",
"E",
""
],
[
"Gesa",
"L",
""
],
[
"Grimani",
"C",
""
],
[
"Lloro",
"I",
""
],
[
"Lobo",
"A",
""
],
[
"Mateos",
"I",
""
]... | The Data and Diagnostics Subsystem of the LTP hardware and software are at present essentially ready for delivery. In this presentation we intend to describe the scientific and technical aspects of this subsystem, which includes thermal diagnostics, magnetic diagnostics and a Radiation Monitor, as well as the prospects... |
2102.02556 | David Burton | C. Fiedler, D.A. Burton | Analogue Hawking temperature of a laser-driven plasma | 12 pages. Green OA version of an article accepted for publication by
Physics Letters A | Phys. Lett. A 403 (2021) 127380 | 10.1016/j.physleta.2021.127380 | null | gr-qc physics.plasm-ph | http://creativecommons.org/licenses/by-nc-nd/4.0/ | We present a method for exploring analogue Hawking radiation using a laser
pulse propagating through an underdense plasma. The propagating fields in the
Hawking effect are local perturbations of the plasma density and laser
amplitude. We derive the dependence of the resulting Hawking temperature on the
dimensionless ... | [
{
"created": "Thu, 4 Feb 2021 11:45:56 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Apr 2021 09:09:22 GMT",
"version": "v2"
}
] | 2021-05-04 | [
[
"Fiedler",
"C.",
""
],
[
"Burton",
"D. A.",
""
]
] | We present a method for exploring analogue Hawking radiation using a laser pulse propagating through an underdense plasma. The propagating fields in the Hawking effect are local perturbations of the plasma density and laser amplitude. We derive the dependence of the resulting Hawking temperature on the dimensionless am... |
1802.02728 | Ryotaro Kase | Ryotaro Kase, Shinji Tsujikawa | Dark energy scenario consistent with GW170817 in theories beyond
Horndeski gravity | 23 pages, 7 figures, published version | Phys. Rev. D 97, 103501 (2018) | 10.1103/PhysRevD.97.103501 | null | gr-qc astro-ph.CO hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Gleyzes-Langlois-Piazza-Vernizzi (GLPV) theories up to quartic order are
the general scheme of scalar-tensor theories allowing the possibility for
realizing the tensor propagation speed $c_t$ equivalent to 1 on the isotropic
cosmological background. We propose a dark energy model in which the late-time
cosmic acc... | [
{
"created": "Thu, 8 Feb 2018 06:58:31 GMT",
"version": "v1"
},
{
"created": "Wed, 2 May 2018 09:17:48 GMT",
"version": "v2"
}
] | 2018-05-03 | [
[
"Kase",
"Ryotaro",
""
],
[
"Tsujikawa",
"Shinji",
""
]
] | The Gleyzes-Langlois-Piazza-Vernizzi (GLPV) theories up to quartic order are the general scheme of scalar-tensor theories allowing the possibility for realizing the tensor propagation speed $c_t$ equivalent to 1 on the isotropic cosmological background. We propose a dark energy model in which the late-time cosmic accel... |
1912.00601 | Shahab Shahidi | Zahra Haghani and Shahab Shahidi | Cosmology in theories with derivative matter coupling | 13 pages | Phys. Dark Univ. 30 (2020) 100683 | 10.1016/j.dark.2020.100683 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new class of modified gravity theories with a healthy higher order
derivative terms of a function of the matter Lagrangian $f(L_m)$ is considered.
Generally the energy momentum tensor is not conserved, leading to the fifth
force similar to $f(R,T)$ theories. We will however show that in the FRW
background there exi... | [
{
"created": "Mon, 2 Dec 2019 07:14:35 GMT",
"version": "v1"
}
] | 2021-04-19 | [
[
"Haghani",
"Zahra",
""
],
[
"Shahidi",
"Shahab",
""
]
] | A new class of modified gravity theories with a healthy higher order derivative terms of a function of the matter Lagrangian $f(L_m)$ is considered. Generally the energy momentum tensor is not conserved, leading to the fifth force similar to $f(R,T)$ theories. We will however show that in the FRW background there exist... |
2210.01574 | Zhe Feng | Zhe Feng | Charged anisotropic white dwarfs in $f\left({R}, {T}\right)$ gravity | 7 pages, 4 figures | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of $f\left(R, T\right) = R + 2 \beta T$ gravity, where $R$ is
the Ricci scalar and $T$ is the trace of the energy-momentum tensor, the
equilibrium structure of charged anisotropic white dwarfs (WDs) is studied. The
stellar equations for the general case are derived and numerical solutions are
found for... | [
{
"created": "Fri, 30 Sep 2022 06:34:43 GMT",
"version": "v1"
}
] | 2022-10-05 | [
[
"Feng",
"Zhe",
""
]
] | In the context of $f\left(R, T\right) = R + 2 \beta T$ gravity, where $R$ is the Ricci scalar and $T$ is the trace of the energy-momentum tensor, the equilibrium structure of charged anisotropic white dwarfs (WDs) is studied. The stellar equations for the general case are derived and numerical solutions are found for t... |
gr-qc/9705011 | Jack Gegenberg | H. Zaidi and J. Gegenberg | Back Reaction of Hawking Radiation on Black Hole Geometry | Latex file, 15 pages, 4 figures enclosed, uses epsf | Phys.Rev. D57 (1998) 1112-1117 | 10.1103/PhysRevD.57.1112 | null | gr-qc hep-th | null | We propose a model for the geometry of a dynamical spherical shell in which
the metric is asymptotically Schwarzschild, but deviates from Ricci-flatness in
a finite neighbourhood of the shell. Hence, the geometry corresponds to a
`hairy' black hole, with the hair originating on the shell. The metric is
regular for an... | [
{
"created": "Wed, 7 May 1997 14:53:31 GMT",
"version": "v1"
}
] | 2016-08-31 | [
[
"Zaidi",
"H.",
""
],
[
"Gegenberg",
"J.",
""
]
] | We propose a model for the geometry of a dynamical spherical shell in which the metric is asymptotically Schwarzschild, but deviates from Ricci-flatness in a finite neighbourhood of the shell. Hence, the geometry corresponds to a `hairy' black hole, with the hair originating on the shell. The metric is regular for an i... |
2101.12108 | Luis Herrera | L. Herrera, A. Di Prisco, J. Ospino | Hyperbolically symmetric static fluids: A general study | 14 pages Revtex. Published in Phys.Rev.D | Physical Review D103, 024037 (2021) | 10.1103/PhysRevD.103.024037 | null | gr-qc | http://creativecommons.org/licenses/by-nc-sa/4.0/ | We carry on a comprehensive study on static fluid distributions endowed with
hyperbolical symmetry. Their physical properties are analyzed in detail. The
energy density appears to be necessarily negative, which suggests that any
possible application of this kind of fluids requires extreme physical
conditions where qu... | [
{
"created": "Thu, 28 Jan 2021 16:51:56 GMT",
"version": "v1"
}
] | 2021-02-03 | [
[
"Herrera",
"L.",
""
],
[
"Di Prisco",
"A.",
""
],
[
"Ospino",
"J.",
""
]
] | We carry on a comprehensive study on static fluid distributions endowed with hyperbolical symmetry. Their physical properties are analyzed in detail. The energy density appears to be necessarily negative, which suggests that any possible application of this kind of fluids requires extreme physical conditions where quan... |
gr-qc/0012017 | C. M. zhang | C.M. Zhang | HBO and Periastron Precession around the X-ray Neutron Star
Magnetosphere | 2 pages, 1 figure, submit to Proceedings of The Ninth Marcel Grossman
Meeting on Gen. Rel. and Grav. at Rome, Italy, July, 2000, Eds. Ruffini, R.
(World Sci. Publisher, Singapore) | null | null | null | gr-qc | null | Based on the periastron precession model to account for kHz QPO of the binary
X-ray neutron star, proposed by Stella and Vietri, we ascribe the 15-60 Hz
Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the
orbiting accreted matter at the boundary of magnetosphere-disk of X-ray neutron
star (... | [
{
"created": "Tue, 5 Dec 2000 12:37:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Zhang",
"C. M.",
""
]
] | Based on the periastron precession model to account for kHz QPO of the binary X-ray neutron star, proposed by Stella and Vietri, we ascribe the 15-60 Hz Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the orbiting accreted matter at the boundary of magnetosphere-disk of X-ray neutron star (NS... |
1205.0258 | Sanved Kolekar | Sanved Kolekar and T. Padmanabhan | Drift, Drag and Brownian motion in the Davies-Unruh bath | v1: 5 pages, no figures, v2: some discussion added, matches published
version | Phys. Rev. D 86, 104057 (2012) | 10.1103/PhysRevD.86.104057 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An interesting feature of the Davies-Unruh effect is that an uniformly
accelerated observer sees an isotropic thermal spectrum of particles even
though there is a preferred direction in this context, determined by the
direction of the acceleration g. We investigate the thermal fluctuations in the
Unruh bath by studyi... | [
{
"created": "Tue, 1 May 2012 20:35:04 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Nov 2012 16:58:45 GMT",
"version": "v2"
}
] | 2012-11-29 | [
[
"Kolekar",
"Sanved",
""
],
[
"Padmanabhan",
"T.",
""
]
] | An interesting feature of the Davies-Unruh effect is that an uniformly accelerated observer sees an isotropic thermal spectrum of particles even though there is a preferred direction in this context, determined by the direction of the acceleration g. We investigate the thermal fluctuations in the Unruh bath by studying... |
gr-qc/0310102 | Navin Singh | S.C. Tiwari | Unimodular relativity and cosmological constant : Comments | Submitted to Journal of Mathematical Physics; correspondence to
vns_sctiwari@yahoo.com | null | null | null | gr-qc | null | We show that the conclusion that matter stress-energy tensor satisfies the
usual covariant continuity law, and the cosmological constant is still a
constant of integration arrived at by Finkelstein et al (42, 340, 2001) is not
valid.
| [
{
"created": "Wed, 22 Oct 2003 06:37:50 GMT",
"version": "v1"
}
] | 2009-09-29 | [
[
"Tiwari",
"S. C.",
""
]
] | We show that the conclusion that matter stress-energy tensor satisfies the usual covariant continuity law, and the cosmological constant is still a constant of integration arrived at by Finkelstein et al (42, 340, 2001) is not valid. |
1812.08937 | Parampreet Singh | Sahil Saini, Parampreet Singh | Generic absence of strong singularities and geodesic completeness in
modified loop quantum cosmologies | Minor revision to match published version in CQG | Class.Quant.Grav. 36 (2019) 105014 | 10.1088/1361-6382/ab1274 | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Different regularizations of the Hamiltonian constraint in loop quantum
cosmology yield modified loop quantum cosmologies, namely mLQC-I and mLQC-II,
which lead to qualitatively different Planck scale physics. We perform a
comprehensive analysis of resolution of various singularities in these modified
loop cosmologie... | [
{
"created": "Fri, 21 Dec 2018 04:15:35 GMT",
"version": "v1"
},
{
"created": "Thu, 23 May 2019 11:35:21 GMT",
"version": "v2"
}
] | 2019-05-24 | [
[
"Saini",
"Sahil",
""
],
[
"Singh",
"Parampreet",
""
]
] | Different regularizations of the Hamiltonian constraint in loop quantum cosmology yield modified loop quantum cosmologies, namely mLQC-I and mLQC-II, which lead to qualitatively different Planck scale physics. We perform a comprehensive analysis of resolution of various singularities in these modified loop cosmologies ... |
1507.03382 | B. S. Ratanpal | B. S. Ratanpal, V. O. Thomas and D. M. Pandya | A new class of solutions of anisotropic charged distributions on
pseudo-spheroidal spacetime | 21 pages, 12 figures and 2 tables | Astrophys Space Sci (2015) 360:53 | 10.1007/s10509-015-2568-0 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the present article a new class of exact solutions of Einstein's field
equations for charged anisotropic distribution is obtained on the background of
pseudo-spheroidal spacetime characterized by the metric potential
$g_{rr}=\frac{1+K\frac{r^2}{R^2}}{1+\frac{r^2}{R^2}}$, where $K$ and $R$ are
geometric parameters ... | [
{
"created": "Mon, 13 Jul 2015 10:12:41 GMT",
"version": "v1"
}
] | 2016-04-07 | [
[
"Ratanpal",
"B. S.",
""
],
[
"Thomas",
"V. O.",
""
],
[
"Pandya",
"D. M.",
""
]
] | In the present article a new class of exact solutions of Einstein's field equations for charged anisotropic distribution is obtained on the background of pseudo-spheroidal spacetime characterized by the metric potential $g_{rr}=\frac{1+K\frac{r^2}{R^2}}{1+\frac{r^2}{R^2}}$, where $K$ and $R$ are geometric parameters of... |
2104.11236 | Lorenzo Annulli | Lorenzo Annulli, Vitor Cardoso, Leonardo Gualtieri | Applications of the close-limit approximation: horizonless compact
objects and scalar fields | 16 pages, 4 figures. Matches published version in CQG | Class.Quant.Grav. 39 (2022) 10, 105005 | 10.1088/1361-6382/ac6410 | null | gr-qc astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The ability to model the evolution of compact binaries from the inspiral to
coalescence is central to gravitational wave astronomy. Current waveform
catalogues are built from vacuum binary black hole models, by evolving Einstein
equations numerically and complementing them with knowledge from slow-motion
expansions. ... | [
{
"created": "Thu, 22 Apr 2021 18:00:00 GMT",
"version": "v1"
},
{
"created": "Thu, 19 May 2022 16:26:10 GMT",
"version": "v2"
}
] | 2022-05-20 | [
[
"Annulli",
"Lorenzo",
""
],
[
"Cardoso",
"Vitor",
""
],
[
"Gualtieri",
"Leonardo",
""
]
] | The ability to model the evolution of compact binaries from the inspiral to coalescence is central to gravitational wave astronomy. Current waveform catalogues are built from vacuum binary black hole models, by evolving Einstein equations numerically and complementing them with knowledge from slow-motion expansions. Mu... |
2010.09173 | Hwajin Eom | Hwajin Eom, Wontae Kim | On thermal radiation of de Sitter space in the semiclassical
Jackiw-Teitelboim model | 16 pages, 1 figure, comments and references added | Gen Relativ Gravit 54, 104 (2022) | 10.1007/s10714-022-02994-5 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In general, the Gibbons-Hawking temperature based on the Euclidean functional
approach shows that de Sitter space in the Bunch-Davies vacuum is globally
thermal. In the exactly soluble semiclassical Jackiw-Teitelboim model, we
investigate thermal property of de Sitter space by taking into account the
quantum back rea... | [
{
"created": "Mon, 19 Oct 2020 02:29:39 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Jan 2021 07:32:11 GMT",
"version": "v2"
},
{
"created": "Tue, 26 Oct 2021 05:58:48 GMT",
"version": "v3"
},
{
"created": "Thu, 15 Sep 2022 02:44:56 GMT",
"version": "v4"
}
] | 2022-09-16 | [
[
"Eom",
"Hwajin",
""
],
[
"Kim",
"Wontae",
""
]
] | In general, the Gibbons-Hawking temperature based on the Euclidean functional approach shows that de Sitter space in the Bunch-Davies vacuum is globally thermal. In the exactly soluble semiclassical Jackiw-Teitelboim model, we investigate thermal property of de Sitter space by taking into account the quantum back react... |
1905.03227 | Shubham Maheshwari | K. Sravan Kumar, Shubham Maheshwari, Anupam Mazumdar | Perturbations in higher derivative gravity beyond maximally symmetric
spacetimes | 36 pages, 1 figure | Phys. Rev. D 100, 064022 (2019) | 10.1103/PhysRevD.100.064022 | null | gr-qc astro-ph.CO hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study (covariant) scalar-vector-tensor (SVT) perturbations of infinite
derivative gravity (IDG), at the quadratic level of the action, around
conformally-flat, covariantly constant curvature backgrounds which are not
maximally symmetric spacetimes (MSS). This extends a previous analysis of
perturbations done aroun... | [
{
"created": "Wed, 8 May 2019 17:30:30 GMT",
"version": "v1"
}
] | 2019-09-18 | [
[
"Kumar",
"K. Sravan",
""
],
[
"Maheshwari",
"Shubham",
""
],
[
"Mazumdar",
"Anupam",
""
]
] | We study (covariant) scalar-vector-tensor (SVT) perturbations of infinite derivative gravity (IDG), at the quadratic level of the action, around conformally-flat, covariantly constant curvature backgrounds which are not maximally symmetric spacetimes (MSS). This extends a previous analysis of perturbations done around ... |
2208.12538 | Reginald Christian Bernardo | Reginald Christian Bernardo and Kin-Wang Ng | Stochastic gravitational wave background phenomenology in a pulsar
timing array | 28 pages, 5 figures, discussion improved, to appear in PRD, see
implementation `PTAfast' https://github.com/reggiebernardo/PTAfast | Phys. Rev. D 107, 044007 (2023) | 10.1103/PhysRevD.107.044007 | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Pulsar timing offers an independent avenue to test general relativity and
alternative gravity theories. This requires an understanding of how metric
polarizations beyond the familiar transverse tensor ones imprint as a
stochastic gravitational wave background and correlate the arrival time of
radio pulses from a pair... | [
{
"created": "Fri, 26 Aug 2022 09:54:41 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Jan 2023 10:54:35 GMT",
"version": "v2"
}
] | 2023-02-08 | [
[
"Bernardo",
"Reginald Christian",
""
],
[
"Ng",
"Kin-Wang",
""
]
] | Pulsar timing offers an independent avenue to test general relativity and alternative gravity theories. This requires an understanding of how metric polarizations beyond the familiar transverse tensor ones imprint as a stochastic gravitational wave background and correlate the arrival time of radio pulses from a pair o... |
2210.02861 | Vasilis Oikonomou | V.K. Oikonomou | Effects of a Pre-inflationary de Sitter Bounce on the Primordial
Gravitational Waves in $f(R)$ Gravity Theories | Nuclear Physics B in press. arXiv admin note: text overlap with
arXiv:2209.09781 | null | 10.1016/j.nuclphysb.2022.115985 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we examine the effects of a pre-inflationary de Sitter bounce on
the energy spectrum of the primordial gravitational waves. Specifically we
assume that the Universe is described by several evolution patches, starting
with a de Sitter pre-inflationary bounce which is followed by an quasi-de
Sitter slow-ro... | [
{
"created": "Thu, 6 Oct 2022 12:21:10 GMT",
"version": "v1"
}
] | 2022-10-19 | [
[
"Oikonomou",
"V. K.",
""
]
] | In this work we examine the effects of a pre-inflationary de Sitter bounce on the energy spectrum of the primordial gravitational waves. Specifically we assume that the Universe is described by several evolution patches, starting with a de Sitter pre-inflationary bounce which is followed by an quasi-de Sitter slow-roll... |
1911.00541 | Emanuele Berti | Emanuele Berti | Topical Collection: Testing the Kerr spacetime with gravitational-wave
and electromagnetic observations | Introduction to the General Relativity and Gravitation Topical
Collection "Testing the Kerr spacetime with gravitational-wave and
electromagnetic observations", available at
https://link.springer.com/journal/10714/topicalCollection/AC_9f63b87d155730bc7589edb13e509026 | Gen Relativ Gravit 51, 140 (2019) | 10.1007/s10714-019-2622-2 | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | One of the Holy Grails of observational astronomy is to confirm the
prediction that black holes in the Universe are described by the Kerr solution
of Einstein's field equations of general relativity. This Topical Collection
provides a status report of theoretical and experimental progress towards
confirming the "Kerr... | [
{
"created": "Fri, 1 Nov 2019 18:28:51 GMT",
"version": "v1"
}
] | 2019-11-05 | [
[
"Berti",
"Emanuele",
""
]
] | One of the Holy Grails of observational astronomy is to confirm the prediction that black holes in the Universe are described by the Kerr solution of Einstein's field equations of general relativity. This Topical Collection provides a status report of theoretical and experimental progress towards confirming the "Kerr p... |
gr-qc/9905043 | Kleidis Kostas | K. Kleidis and D. B. Papadopoulos | On the adiabatic expansion of the visible space in a higher-dimensional
Cosmology | LaTex file, 14 pages | Gen.Rel.Grav. 29 (1997) 275 | 10.1023/A:1010264717346 | null | gr-qc | null | In the context of higher-dimensional cosmologies with isotropic visible and
internal space and multi-perfect fluid matter, we study the conditions under
which adiabatic expansion of the visoble external space is possible, when a
time-dependent internal space is present. The analysis is based on a
reinterpretation of ... | [
{
"created": "Thu, 13 May 1999 12:38:06 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Kleidis",
"K.",
""
],
[
"Papadopoulos",
"D. B.",
""
]
] | In the context of higher-dimensional cosmologies with isotropic visible and internal space and multi-perfect fluid matter, we study the conditions under which adiabatic expansion of the visoble external space is possible, when a time-dependent internal space is present. The analysis is based on a reinterpretation of th... |
1601.07395 | Nils Andersson | N. Andersson, S. Wells and J.A. Vickers | Quantised vortices and mutual friction in relativistic superfluids | 9 pages, RevTeX | null | 10.1088/0264-9381/33/24/245010 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the detailed dynamics of an array of quantised superfluid
vortices in the framework of general relativity, as required for quantitative
modelling of realistic neutron star cores. Our model builds on the variational
approach to relativistic (multi-) fluid dynamics, where the vorticity plays a
central role.... | [
{
"created": "Wed, 27 Jan 2016 14:55:38 GMT",
"version": "v1"
}
] | 2016-12-07 | [
[
"Andersson",
"N.",
""
],
[
"Wells",
"S.",
""
],
[
"Vickers",
"J. A.",
""
]
] | We consider the detailed dynamics of an array of quantised superfluid vortices in the framework of general relativity, as required for quantitative modelling of realistic neutron star cores. Our model builds on the variational approach to relativistic (multi-) fluid dynamics, where the vorticity plays a central role. T... |
gr-qc/9911037 | Plamen Fiziev | P. P. Fiziev | A Minimal Model for Dilatonic Gravity | 10 pages, LaTeX, no figures. A new Appendex added, new references,
comments and acknowledgments added, typos corrected. Final version: to appear
in Modern Physics Letters A | null | 10.1142/S0217732300002553 | SU-FzF: 4/99 | gr-qc astro-ph hep-ph hep-th | null | We study a new minimal scalar-tensor model of gravity with Brans-Dicke factor
$\omega(\Phi)\equiv 0$ and cosmological factor $\Pi(\Phi)$. The constraints on
$\Pi(\Phi)$ from known gravitational experiments are derived. We show that
almost any time evolution of the scale factor in a homogeneous isotropic
Universe can ... | [
{
"created": "Wed, 10 Nov 1999 07:40:10 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Jan 2000 12:58:54 GMT",
"version": "v2"
},
{
"created": "Sat, 2 Dec 2000 15:50:59 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Fiziev",
"P. P.",
""
]
] | We study a new minimal scalar-tensor model of gravity with Brans-Dicke factor $\omega(\Phi)\equiv 0$ and cosmological factor $\Pi(\Phi)$. The constraints on $\Pi(\Phi)$ from known gravitational experiments are derived. We show that almost any time evolution of the scale factor in a homogeneous isotropic Universe can be... |
1508.05126 | Fay\c{c}al Hammad | Fay\c{c}al Hammad | $f(R)$-Modified Gravity, Wald Entropy, and the Generalized Uncertainty
Principle | 7 pages. Matches the accepted version | Phys. Rev. D 92, 044004 (2015) | 10.1103/PhysRevD.92.044004 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Wald's entropy formula allows one to find the entropy of black holes' event
horizon within any diffeomorphism invariant theory of gravity. When applied to
general relativity, the formula yields the Bekenstein-Hawking result but, for
any other gravitational action that departs from the Hilbert action, the
resulting en... | [
{
"created": "Tue, 4 Aug 2015 21:38:19 GMT",
"version": "v1"
}
] | 2015-08-24 | [
[
"Hammad",
"Fayçal",
""
]
] | Wald's entropy formula allows one to find the entropy of black holes' event horizon within any diffeomorphism invariant theory of gravity. When applied to general relativity, the formula yields the Bekenstein-Hawking result but, for any other gravitational action that departs from the Hilbert action, the resulting entr... |
gr-qc/0512099 | Wenbiao Liu | Wenbiao Liu | New Coordinates for BTZ Black Hole and Hawking Radiation via Tunnelling | null | Phys.Lett. B634 (2006) 541-544 | 10.1016/j.physletb.2006.01.028 | null | gr-qc | null | Hawking radiation can usefully be viewed as a semi-classical tunnelling
process that originates at the black hole horizon. For the stationary
axisymmetric BTZ black hole, a generalized Painleve coordinate system
(Painleve-BTZ coordinates) is introduced, and Hawking radiation as tunnelling
under the effect of self-gra... | [
{
"created": "Fri, 16 Dec 2005 14:21:30 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Liu",
"Wenbiao",
""
]
] | Hawking radiation can usefully be viewed as a semi-classical tunnelling process that originates at the black hole horizon. For the stationary axisymmetric BTZ black hole, a generalized Painleve coordinate system (Painleve-BTZ coordinates) is introduced, and Hawking radiation as tunnelling under the effect of self-gravi... |
1808.06939 | Lorenzo Sebastiani | L. Sebastiani, L. Vanzo, S. Zerbini | On a WKB formula for echoes | 27 pages, references added, accepted in IJGMMP | null | 10.1142/S0219887819501810 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an unified approach for the study of idealized gravitational
compact objects like wormholes and horizonless stars, here simulated by the
presence of boundary conditions at a deeply inner wall. At classical level,
namely neglecting quantum effects, the presence of the wall leads to
characteristic echoes fol... | [
{
"created": "Mon, 20 Aug 2018 08:41:23 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Mar 2019 09:58:51 GMT",
"version": "v2"
},
{
"created": "Wed, 18 Sep 2019 07:32:46 GMT",
"version": "v3"
},
{
"created": "Tue, 8 Oct 2019 12:06:24 GMT",
"version": "v4"
}
] | 2019-11-07 | [
[
"Sebastiani",
"L.",
""
],
[
"Vanzo",
"L.",
""
],
[
"Zerbini",
"S.",
""
]
] | We present an unified approach for the study of idealized gravitational compact objects like wormholes and horizonless stars, here simulated by the presence of boundary conditions at a deeply inner wall. At classical level, namely neglecting quantum effects, the presence of the wall leads to characteristic echoes follo... |
1001.4228 | Catherine Meusburger | Angel Ballesteros, Francisco J. Herranz, Catherine Meusburger | Three-dimensional gravity and Drinfel'd doubles: spacetimes and
symmetries from quantum deformations | 12 pages; minor changes, additional references | Phys.Lett.B687:375-381,2010 | 10.1016/j.physletb.2010.03.043 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show how the constant curvature spacetimes of 3d gravity and the
associated symmetry algebras can be derived from a single quantum deformation
of the 3d Lorentz algebra sl(2,R). We investigate the classical Drinfel'd
double of a "hybrid" deformation of sl(2,R) that depends on two parameters
(\eta,z). With an appro... | [
{
"created": "Sun, 24 Jan 2010 08:17:47 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Mar 2010 12:46:39 GMT",
"version": "v2"
}
] | 2010-04-30 | [
[
"Ballesteros",
"Angel",
""
],
[
"Herranz",
"Francisco J.",
""
],
[
"Meusburger",
"Catherine",
""
]
] | We show how the constant curvature spacetimes of 3d gravity and the associated symmetry algebras can be derived from a single quantum deformation of the 3d Lorentz algebra sl(2,R). We investigate the classical Drinfel'd double of a "hybrid" deformation of sl(2,R) that depends on two parameters (\eta,z). With an appropr... |
1610.09329 | Izzet Sakalli | G. Tokgoz and I. Sakalli | Stationary Scalar Clouds Around Maximally Rotating Linear Dilaton Black
Holes | Accepted for publication in Classical and Quantum Gravity | Class. Quantum Grav. 34 (2017) 125007 | 10.1088/1361-6382/aa6858 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the wave dynamics of a charged massive scalar field
propagating in a maximally rotating (extremal) linear dilaton black hole
geometry. We prove the existence of a discrete and infinite family of
resonances describing non-decaying stationary scalar configurations (clouds)
enclosing these rapidly rotatin... | [
{
"created": "Fri, 28 Oct 2016 18:05:58 GMT",
"version": "v1"
},
{
"created": "Mon, 31 Oct 2016 09:19:41 GMT",
"version": "v2"
},
{
"created": "Sat, 17 Dec 2016 11:50:04 GMT",
"version": "v3"
},
{
"created": "Wed, 22 Mar 2017 17:04:24 GMT",
"version": "v4"
}
] | 2017-09-07 | [
[
"Tokgoz",
"G.",
""
],
[
"Sakalli",
"I.",
""
]
] | We investigate the wave dynamics of a charged massive scalar field propagating in a maximally rotating (extremal) linear dilaton black hole geometry. We prove the existence of a discrete and infinite family of resonances describing non-decaying stationary scalar configurations (clouds) enclosing these rapidly rotating ... |
gr-qc/0502070 | Takeshi Chiba | Takeshi Chiba | Generalized Gravity and a Ghost | 8 pages, a reference added | JCAP 0503 (2005) 008 | 10.1088/1475-7516/2005/03/008 | null | gr-qc astro-ph | null | We show that generalized gravity theories involving the curvature invariants
of the Ricci tensor and the Riemann tensor as well as the Ricci scalar are
equivalent to multi- scalar-tensor gravities with four derivatives terms. By
expanding the action around a vacuum spacetime, the action is reduced to that
of the Eins... | [
{
"created": "Tue, 15 Feb 2005 02:15:20 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Mar 2005 01:53:10 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Chiba",
"Takeshi",
""
]
] | We show that generalized gravity theories involving the curvature invariants of the Ricci tensor and the Riemann tensor as well as the Ricci scalar are equivalent to multi- scalar-tensor gravities with four derivatives terms. By expanding the action around a vacuum spacetime, the action is reduced to that of the Einste... |
1512.01919 | Tao Wang | Tian-Yi Zhao, Towe Wang | Membrane paradigm of black holes in Chern-Simons modified gravity | 16 pages, author information updated | null | 10.1088/1475-7516/2016/06/019 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The membrane paradigm of black hole is studied in the Chern-Simons modified
gravity. Derived with the action principle a la Parikh-Wilczek, the stress
tensor of membrane manifests a rich structure arising from the Chern-Simons
term. The membrane stress tensor, if related to the bulk stress tensor in a
special form, o... | [
{
"created": "Mon, 7 Dec 2015 06:04:17 GMT",
"version": "v1"
},
{
"created": "Sun, 10 Apr 2016 06:11:11 GMT",
"version": "v2"
},
{
"created": "Sun, 5 Jun 2016 07:47:49 GMT",
"version": "v3"
}
] | 2016-06-15 | [
[
"Zhao",
"Tian-Yi",
""
],
[
"Wang",
"Towe",
""
]
] | The membrane paradigm of black hole is studied in the Chern-Simons modified gravity. Derived with the action principle a la Parikh-Wilczek, the stress tensor of membrane manifests a rich structure arising from the Chern-Simons term. The membrane stress tensor, if related to the bulk stress tensor in a special form, obe... |
gr-qc/0310015 | T. R. Mongan | T. R. Mongan | Vacuum dominance and holography | 5 pages, no figures | null | null | null | gr-qc astro-ph hep-ph | null | A cosmological event horizon develops in a vacuum-dominated Friedmann
universe. The Schwarschild radius of the vacuum energy within the horizon
equals the horizon radius. Black hole thermodynamics and the holographic
conjecture indicate a finite number of degrees of freedom within the horizon.
The average energy per ... | [
{
"created": "Thu, 2 Oct 2003 17:50:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mongan",
"T. R.",
""
]
] | A cosmological event horizon develops in a vacuum-dominated Friedmann universe. The Schwarschild radius of the vacuum energy within the horizon equals the horizon radius. Black hole thermodynamics and the holographic conjecture indicate a finite number of degrees of freedom within the horizon. The average energy per de... |
2111.05857 | Wenbin Lin | Hiroaki Nakajima and Wenbin Lin | New Chandrasekhar transformation in Kerr spacetime | 14 pages, accepted for publication in PRD | null | 10.1103/PhysRevD.105.064036 | null | gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | We construct a new type of Chandrasekhar transformation in Kerr spacetime
using the different tortoise coordinate, which is useful for exact analysis to
study Teukolsky equation with arbitrary frequency. We also give the
interpretation of our transformation using the formalism of the quantum
Seiberg-Witten geometry.
| [
{
"created": "Wed, 10 Nov 2021 15:07:12 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Feb 2022 13:51:23 GMT",
"version": "v2"
},
{
"created": "Fri, 4 Mar 2022 01:44:18 GMT",
"version": "v3"
}
] | 2022-04-06 | [
[
"Nakajima",
"Hiroaki",
""
],
[
"Lin",
"Wenbin",
""
]
] | We construct a new type of Chandrasekhar transformation in Kerr spacetime using the different tortoise coordinate, which is useful for exact analysis to study Teukolsky equation with arbitrary frequency. We also give the interpretation of our transformation using the formalism of the quantum Seiberg-Witten geometry. |
1803.04802 | Fabrizio Di Giovanni | Fabrizio Di Giovanni, Nicolas Sanchis-Gual, Carlos A. R. Herdeiro,
Jos\'e A. Font | Dynamical formation of Proca stars and quasi-stationary solitonic
objects | null | Phys. Rev. D 98, 064044 (2018) | 10.1103/PhysRevD.98.064044 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform fully non-linear numerical simulations within the spherically
symmetric Einstein-(complex)Proca system. Starting with Proca field
distributions that obey the Hamiltonian, momentum and Gaussian constraints, we
show that the self-gravity of the system induces the formation of compact
objects, which, for appr... | [
{
"created": "Tue, 13 Mar 2018 13:45:52 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Jun 2019 09:08:09 GMT",
"version": "v2"
}
] | 2019-06-18 | [
[
"Di Giovanni",
"Fabrizio",
""
],
[
"Sanchis-Gual",
"Nicolas",
""
],
[
"Herdeiro",
"Carlos A. R.",
""
],
[
"Font",
"José A.",
""
]
] | We perform fully non-linear numerical simulations within the spherically symmetric Einstein-(complex)Proca system. Starting with Proca field distributions that obey the Hamiltonian, momentum and Gaussian constraints, we show that the self-gravity of the system induces the formation of compact objects, which, for approp... |
1209.5085 | Bernard S. Kay | Bernard S. Kay (York) | Modern foundations for thermodynamics and the stringy limit of black
hole equilibria | 5 pages | null | null | null | gr-qc cond-mat.stat-mech hep-th quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We recall the existing string theory understanding of black hole entropy and
argue it is incomplete but we put forward a modified version, based on the
author's 'matter-gravity entanglement hypothesis', which, we claim, gives a
more satisfactory understanding and also a resolution to the Information Loss
Puzzle. This... | [
{
"created": "Sun, 23 Sep 2012 17:05:25 GMT",
"version": "v1"
}
] | 2012-09-25 | [
[
"Kay",
"Bernard S.",
"",
"York"
]
] | We recall the existing string theory understanding of black hole entropy and argue it is incomplete but we put forward a modified version, based on the author's 'matter-gravity entanglement hypothesis', which, we claim, gives a more satisfactory understanding and also a resolution to the Information Loss Puzzle. This h... |
gr-qc/9704060 | Burkhard Kleihaus | Burkhard Kleihaus and Jutta Kunz (Universit\"at Oldenburg) | Static black hole solutions with axial symmetry | 14 pages, including 4 postscript figures, LaTeX | Phys.Rev.Lett. 79 (1997) 1595-1598 | 10.1103/PhysRevLett.79.1595 | null | gr-qc hep-th | null | We construct a new class of asymptotically flat black hole solutions in
Einstein-Yang-Mills and Einstein-Yang-Mills-dilaton theory. These black hole
solutions are static, and they have a regular event horizon. However, they
possess only axial symmetry. Like their regular counterparts, the black hole
solutions are cha... | [
{
"created": "Wed, 23 Apr 1997 09:43:35 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Kleihaus",
"Burkhard",
"",
"Universität Oldenburg"
],
[
"Kunz",
"Jutta",
"",
"Universität Oldenburg"
]
] | We construct a new class of asymptotically flat black hole solutions in Einstein-Yang-Mills and Einstein-Yang-Mills-dilaton theory. These black hole solutions are static, and they have a regular event horizon. However, they possess only axial symmetry. Like their regular counterparts, the black hole solutions are chara... |
2008.04553 | Xiangdong Zhang | Xiangdong Zhang, Jinsong Yang and Yongge Ma | Canonical loop quantization of the lowest-order projectable Horava
gravity | 8 pages, published version for PRD | Phys. Rev. D 102, 124060 (2020) | 10.1103/PhysRevD.102.124060 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | The Hamiltonian formulation of the lowest-order projectable Horava gravity,
namely the so-called $\lambda$-$R$ gravity, is studied. Since a preferred
foliation has been chosen in projectable Horava gravity, there is no local
Hamiltonian constraint in the theory. In contrast to general relativity, the
constraint algeb... | [
{
"created": "Tue, 11 Aug 2020 07:03:38 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Dec 2020 02:57:29 GMT",
"version": "v2"
}
] | 2021-01-01 | [
[
"Zhang",
"Xiangdong",
""
],
[
"Yang",
"Jinsong",
""
],
[
"Ma",
"Yongge",
""
]
] | The Hamiltonian formulation of the lowest-order projectable Horava gravity, namely the so-called $\lambda$-$R$ gravity, is studied. Since a preferred foliation has been chosen in projectable Horava gravity, there is no local Hamiltonian constraint in the theory. In contrast to general relativity, the constraint algebra... |
2303.06270 | Vasilis Oikonomou | V.K. Oikonomou | Static Neutron Stars Perspective of Quadratic and Induced Inflationary
Attractor Scalar-tensor Theories | CQG Accepted | null | 10.1088/1361-6382/acc2a7 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This study focuses on the static neutron star perspective for two types of
cosmological inflationary attractor theories, namely the induced inflationary
attractors and the quadratic inflationary attractors. The two cosmological
models can be discriminated cosmologically, since one of the two does not
provide a viable... | [
{
"created": "Sat, 11 Mar 2023 01:13:07 GMT",
"version": "v1"
}
] | 2023-03-29 | [
[
"Oikonomou",
"V. K.",
""
]
] | This study focuses on the static neutron star perspective for two types of cosmological inflationary attractor theories, namely the induced inflationary attractors and the quadratic inflationary attractors. The two cosmological models can be discriminated cosmologically, since one of the two does not provide a viable i... |
0908.0579 | Koji Uryu | Koji Uryu, Francois Limousin, John L. Friedman, Eric Gourgoulhon,
Masaru Shibata | Non-conformally flat initial data for binary compact objects | 22 pages, 7 figures | Phys.Rev.D80:124004,2009 | 10.1103/PhysRevD.80.124004 | DPUR-TH-18 | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new method is described for constructing initial data for a binary
neutron-star (BNS) system in quasi-equilibrium circular orbit. Two formulations
for non-conformally flat data, waveless (WL) and near-zone helically symmetric
(NHS), are introduced; in each formulation, the Einstein-Euler system, written
in 3+1 form... | [
{
"created": "Wed, 5 Aug 2009 05:21:50 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Oct 2009 04:53:04 GMT",
"version": "v2"
}
] | 2013-05-29 | [
[
"Uryu",
"Koji",
""
],
[
"Limousin",
"Francois",
""
],
[
"Friedman",
"John L.",
""
],
[
"Gourgoulhon",
"Eric",
""
],
[
"Shibata",
"Masaru",
""
]
] | A new method is described for constructing initial data for a binary neutron-star (BNS) system in quasi-equilibrium circular orbit. Two formulations for non-conformally flat data, waveless (WL) and near-zone helically symmetric (NHS), are introduced; in each formulation, the Einstein-Euler system, written in 3+1 form o... |
1405.3827 | Atsushi Higuchi | Rafael P. Bernar, Lu\'is C. B. Crispino, Atsushi Higuchi | Infrared-finite graviton two-point function in static de Sitter space | 17 pages, REVTeX, references corrected | Phys. Rev. D 90, 024045 (2014) | 10.1103/PhysRevD.90.024045 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study quantum gravitational perturbations in the static patch of de Sitter
space. In particular, we determine the symplectic inner product of these
perturbations and use it to write down the graviton two-point function in the
state analogous to the Bunch-Davies vacuum in a certain gauge. We find this
two-point fun... | [
{
"created": "Thu, 15 May 2014 12:56:27 GMT",
"version": "v1"
},
{
"created": "Fri, 16 May 2014 17:49:46 GMT",
"version": "v2"
}
] | 2014-07-23 | [
[
"Bernar",
"Rafael P.",
""
],
[
"Crispino",
"Luís C. B.",
""
],
[
"Higuchi",
"Atsushi",
""
]
] | We study quantum gravitational perturbations in the static patch of de Sitter space. In particular, we determine the symplectic inner product of these perturbations and use it to write down the graviton two-point function in the state analogous to the Bunch-Davies vacuum in a certain gauge. We find this two-point funct... |
gr-qc/9507010 | Jerose Martin | Y. Kubyshin and J. Martin | Limits on Kaluza-Klein Models from COBE Results | 9 pages, Latex, one figure available on request at the following
adress: jmartin@ccr.jussieu.fr | null | null | UB-ECM-PF 95/13, LGCR 95/06/05, DAMTP R95/35 | gr-qc | null | The large-angular-scale anisotropy of the cosmic microwave background
radiation in multidimensional cosmological models (Kaluza-Klein models) is
studied. Limits on parameters of the models imposed by the experimental data
are obtained. It is shown that in principle there is a room for Kaluza-Klein
models as possible ... | [
{
"created": "Wed, 5 Jul 1995 15:22:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Kubyshin",
"Y.",
""
],
[
"Martin",
"J.",
""
]
] | The large-angular-scale anisotropy of the cosmic microwave background radiation in multidimensional cosmological models (Kaluza-Klein models) is studied. Limits on parameters of the models imposed by the experimental data are obtained. It is shown that in principle there is a room for Kaluza-Klein models as possible ca... |
gr-qc/0607071 | Miguel Gustavo de Campos Batista | M. de Campos | A study of gravitational collapse with decaying of the vacuum energy | 9 pages, 3 figures | null | null | null | gr-qc | null | We study the gravitational collapse of a dust dark matter star in a
$\Lambda$-background. We consider two distinct cases: First we do not have a
dark matter and dark energy coupling; second, we consider that $\Lambda $ decay
in dark particles. The approach adopted assumes a modified matter expansion
rate and we have ... | [
{
"created": "Tue, 18 Jul 2006 15:26:36 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Sep 2006 22:56:58 GMT",
"version": "v2"
},
{
"created": "Tue, 7 Nov 2006 15:12:01 GMT",
"version": "v3"
}
] | 2007-05-23 | [
[
"de Campos",
"M.",
""
]
] | We study the gravitational collapse of a dust dark matter star in a $\Lambda$-background. We consider two distinct cases: First we do not have a dark matter and dark energy coupling; second, we consider that $\Lambda $ decay in dark particles. The approach adopted assumes a modified matter expansion rate and we have fo... |
gr-qc/0001093 | Garcia | L.C.Garcia de Andrade | On String Cosmology and de Sitter inflation with massless dilatons and
dynamical torsion | Latex file Kb | null | null | null | gr-qc | null | Variation of the 4-D string cosmology action with dynamical torsion and
massless dilatons lead to an expression of torsion in terms of massless
dilatons in the case of de Sitter inflation.The solution is approximated
according to the COBE data.
| [
{
"created": "Fri, 28 Jan 2000 12:03:04 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"de Andrade",
"L. C. Garcia",
""
]
] | Variation of the 4-D string cosmology action with dynamical torsion and massless dilatons lead to an expression of torsion in terms of massless dilatons in the case of de Sitter inflation.The solution is approximated according to the COBE data. |
2208.08098 | Mohammad Vahid Takook | M.V. Takook | Conceptual and technical challenges of quantum gravity | 17 pages, typos corrected | Int. J. Theor. Phys., 59 (2020) 2540 | 10.1007/s10773-020-04520-2 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | The appearance of infinity together with collapsing quantum state due to the
observation or interaction, which are two challenging features of quantum field
theory, become very serious problems in quantum gravity as well as in quantum
geometry of space-time. These problems can be divided into two categories:
technica... | [
{
"created": "Wed, 17 Aug 2022 06:23:42 GMT",
"version": "v1"
}
] | 2023-04-14 | [
[
"Takook",
"M. V.",
""
]
] | The appearance of infinity together with collapsing quantum state due to the observation or interaction, which are two challenging features of quantum field theory, become very serious problems in quantum gravity as well as in quantum geometry of space-time. These problems can be divided into two categories: technical ... |
1711.06859 | Seema Satin | Seema Satin | Induced Perturbations and Stochastic effects in Collapsing Relativistic
Stars | null | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a modified model for relativistic stars which are usually
represented by perfect fluids. Fluctuations of the stress tensor act as source
in the modified Einstein's equation, giving it a Langevin equation form. The
occurrence of these fluctuations is attributed to the microphysics of the
interior of the sta... | [
{
"created": "Sat, 18 Nov 2017 13:23:14 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Dec 2017 13:39:58 GMT",
"version": "v2"
}
] | 2017-12-07 | [
[
"Satin",
"Seema",
""
]
] | We present a modified model for relativistic stars which are usually represented by perfect fluids. Fluctuations of the stress tensor act as source in the modified Einstein's equation, giving it a Langevin equation form. The occurrence of these fluctuations is attributed to the microphysics of the interior of the star ... |
1905.05612 | Pameli Saha Ms. | Pameli Saha and Ujjal Debnath | Collision of particles near charged MSW black hole in 2 + 1 dimensions | 14 pages, 12 figures | Modern Physics Letters A, Vol. 34 (2019) 1950127 | 10.1142/S021773231950127X | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Here, we explore the dynamics of particle near the horizon of charged
Mandal-Sengupta-Wadia (MSW) black hole in 2+1 dimensions. It results analysis
of angular momentum and potential energy for null and time-like geodesics. We
also appraise the high center-of-mass energy of coming particles from rest at
infinity near ... | [
{
"created": "Sat, 11 May 2019 12:23:51 GMT",
"version": "v1"
}
] | 2019-05-15 | [
[
"Saha",
"Pameli",
""
],
[
"Debnath",
"Ujjal",
""
]
] | Here, we explore the dynamics of particle near the horizon of charged Mandal-Sengupta-Wadia (MSW) black hole in 2+1 dimensions. It results analysis of angular momentum and potential energy for null and time-like geodesics. We also appraise the high center-of-mass energy of coming particles from rest at infinity near th... |
0811.4592 | Hristu Culetu | Hristu Culetu | Comments on : Frame dragging anomalies for rotating bodies | 3 pages, no figures, 2 references and comments added | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that Collas and Klein (ArXiv : 0811.2471 [gr-qc]) wrongly
concluded that "negative frame dragging" phenomenon takes place at all finite
$r$ and $z$ coordinate values . We argue that a test particle with zero angular
momentum counter-rotates with respect to the source in the "time machine"
region only. In ... | [
{
"created": "Thu, 27 Nov 2008 17:13:46 GMT",
"version": "v1"
},
{
"created": "Sun, 28 Dec 2008 12:31:43 GMT",
"version": "v2"
}
] | 2008-12-28 | [
[
"Culetu",
"Hristu",
""
]
] | It is shown that Collas and Klein (ArXiv : 0811.2471 [gr-qc]) wrongly concluded that "negative frame dragging" phenomenon takes place at all finite $r$ and $z$ coordinate values . We argue that a test particle with zero angular momentum counter-rotates with respect to the source in the "time machine" region only. In ad... |
1301.1073 | Carlos A. R. Herdeiro | F. S. Coelho, C. Herdeiro, C. Rebelo and M. O. P. Sampaio | Radiation from a D-dimensional collision of shock waves: an insight
allowed by the D parameter | 3 pages; contribution to the proceedings of the Thirteenth Marcel
Grossmann Meeting, Stockholm University, Sweden, 1-7 July, 2012; based on a
talk in the AT1 "Higher Dimensional General Relativity" parallel session | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the radiation emitted in a collision of shock waves, in
D-dimensional General Relativity (GR), and describe a remarkably simple
pattern, hinting at a more fundamental structure, unveiled by the introduction
of the parameter D.
| [
{
"created": "Sun, 6 Jan 2013 22:58:08 GMT",
"version": "v1"
}
] | 2013-01-08 | [
[
"Coelho",
"F. S.",
""
],
[
"Herdeiro",
"C.",
""
],
[
"Rebelo",
"C.",
""
],
[
"Sampaio",
"M. O. P.",
""
]
] | We consider the radiation emitted in a collision of shock waves, in D-dimensional General Relativity (GR), and describe a remarkably simple pattern, hinting at a more fundamental structure, unveiled by the introduction of the parameter D. |
2205.08865 | Suman Ghosh | Vivek Sharma and Suman Ghosh | Geodesic Congruences in 5D Warped Ellis-Bronnikov Spacetimes | 19+5 preprint pages, 11 figures; references added, version accepted
in EPJ Plus | null | null | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | We study the timelike geodesic congruences in the generalized Ellis-Bronnikov
spacetime (4D-GEB) and in recently proposed 5D model where a 4D-GEB is embedded
in a warped geometry (5D-WGEB) and conduct a comparative study. Analytical
expressions of ESR variables (for 4D geometries) are found which reveal the
role of t... | [
{
"created": "Wed, 18 May 2022 11:17:16 GMT",
"version": "v1"
},
{
"created": "Fri, 20 May 2022 04:23:43 GMT",
"version": "v2"
},
{
"created": "Fri, 12 Aug 2022 07:53:55 GMT",
"version": "v3"
}
] | 2022-08-15 | [
[
"Sharma",
"Vivek",
""
],
[
"Ghosh",
"Suman",
""
]
] | We study the timelike geodesic congruences in the generalized Ellis-Bronnikov spacetime (4D-GEB) and in recently proposed 5D model where a 4D-GEB is embedded in a warped geometry (5D-WGEB) and conduct a comparative study. Analytical expressions of ESR variables (for 4D geometries) are found which reveal the role of the... |
2403.15205 | Jean-Luc Lehners | Jean-Luc Lehners and Jerome Quintin | Delicate curvature bounces in the no-boundary wave function and in the
late universe | 26 pages, 14 figures | null | null | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Theoretical considerations motivate us to consider vacuum energy to be able
to decay and to assume that the spatial geometry of the universe is closed.
Combining both aspects leads to the possibility that the universe, or certain
regions thereof, can collapse and subsequently undergo a curvature bounce. This
may have... | [
{
"created": "Fri, 22 Mar 2024 13:46:56 GMT",
"version": "v1"
}
] | 2024-03-25 | [
[
"Lehners",
"Jean-Luc",
""
],
[
"Quintin",
"Jerome",
""
]
] | Theoretical considerations motivate us to consider vacuum energy to be able to decay and to assume that the spatial geometry of the universe is closed. Combining both aspects leads to the possibility that the universe, or certain regions thereof, can collapse and subsequently undergo a curvature bounce. This may have o... |
1012.1695 | Subenoy Chakraborty | Subenoy Chakraborty, Nairwita Mazumder, Ritabrata Biswas | Hawking radiation as tunnelling from the trapping horizon of a general
non-static spherically symmetric space-time | 8pages | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using tunnelling approach, Hawking radiation is derived for a general class
of non-static spherically symmetric space time. The standard tunnelling rate
formula is obtained using the unified first law of thermodynamics on the
trapping horizon and Hawking temperature is measured by an Kodama observer
inside the horizo... | [
{
"created": "Wed, 8 Dec 2010 07:12:36 GMT",
"version": "v1"
}
] | 2010-12-09 | [
[
"Chakraborty",
"Subenoy",
""
],
[
"Mazumder",
"Nairwita",
""
],
[
"Biswas",
"Ritabrata",
""
]
] | Using tunnelling approach, Hawking radiation is derived for a general class of non-static spherically symmetric space time. The standard tunnelling rate formula is obtained using the unified first law of thermodynamics on the trapping horizon and Hawking temperature is measured by an Kodama observer inside the horizon. |
1305.2662 | Ronaldo S. S. Vieira | Ronaldo S. S. Vieira, Patricio S. Letelier | Thin-disk models in an Integrable Weyl-Dirac theory | 18 pages, 3 figures; accepted in General Relativity and Gravitation | Gen. Relativ. Gravit. (2014) 46:1641 | 10.1007/s10714-013-1641-7 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a class of static, axially symmetric solutions representing
razor-thin disks of matter in an Integrable Weyl-Dirac theory proposed in
Found. Phys. 29, 1303 (1999). The main differences between these solutions and
the corresponding general relativistic one are analyzed, focusing on the
behavior of physica... | [
{
"created": "Mon, 13 May 2013 02:55:27 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Feb 2014 21:46:41 GMT",
"version": "v2"
}
] | 2014-02-13 | [
[
"Vieira",
"Ronaldo S. S.",
""
],
[
"Letelier",
"Patricio S.",
""
]
] | We construct a class of static, axially symmetric solutions representing razor-thin disks of matter in an Integrable Weyl-Dirac theory proposed in Found. Phys. 29, 1303 (1999). The main differences between these solutions and the corresponding general relativistic one are analyzed, focusing on the behavior of physical ... |
2008.04609 | Chen Lan | Chen Lan, Yan-Gang Miao and Hao Yang | Quasinormal Modes and Thermodynamics of Regular Black Holes | published version | Nucl. Phys. B 971 (2021) 115539 | 10.1016/j.nuclphysb.2021.115539 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | By applying the dimensionless scheme, we investigate the quasinormal modes
and phase transitions analytically for three types of regular black holes. The
universal deviations to the first law of mechanics in regular black holes are
proved. Meanwhile, we verify that second order phase transitions and Davies
points sti... | [
{
"created": "Tue, 11 Aug 2020 10:09:40 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Aug 2020 13:47:43 GMT",
"version": "v2"
},
{
"created": "Thu, 9 Sep 2021 01:39:23 GMT",
"version": "v3"
}
] | 2022-05-13 | [
[
"Lan",
"Chen",
""
],
[
"Miao",
"Yan-Gang",
""
],
[
"Yang",
"Hao",
""
]
] | By applying the dimensionless scheme, we investigate the quasinormal modes and phase transitions analytically for three types of regular black holes. The universal deviations to the first law of mechanics in regular black holes are proved. Meanwhile, we verify that second order phase transitions and Davies points still... |
1411.6218 | Hao Wei | Xiao-Peng Yan, De-Zi Liu, Hao Wei | Age Problem in Lemaitre-Tolman-Bondi Void Models | 17 pages, 9 figures, revtex4; v2: discussions added, Phys. Lett. B in
press; v3: published version | Phys.Lett.B742:149-159,2015 | 10.1016/j.physletb.2015.01.029 | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | As is well known, one can explain the current cosmic acceleration by
considering an inhomogeneous and/or anisotropic universe (which violates the
cosmological principle), without invoking dark energy or modified gravity. The
well-known one of this kind of models is the so-called
Lema\^{\i}tre-Tolman-Bondi (LTB) void ... | [
{
"created": "Sun, 23 Nov 2014 10:00:00 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Jan 2015 10:15:00 GMT",
"version": "v2"
},
{
"created": "Tue, 3 Feb 2015 10:00:00 GMT",
"version": "v3"
}
] | 2015-02-04 | [
[
"Yan",
"Xiao-Peng",
""
],
[
"Liu",
"De-Zi",
""
],
[
"Wei",
"Hao",
""
]
] | As is well known, one can explain the current cosmic acceleration by considering an inhomogeneous and/or anisotropic universe (which violates the cosmological principle), without invoking dark energy or modified gravity. The well-known one of this kind of models is the so-called Lema\^{\i}tre-Tolman-Bondi (LTB) void mo... |
1112.2886 | Sylvain Carrozza | Sylvain Carrozza | Singular topologies in the Boulatov model | 4 pages; proceedings of Loops'11 (May 2011, Madrid); v2: minor
modifications matching published version | J. Phys.: Conf. Ser. 360 012045 (2012) | 10.1088/1742-6596/360/1/012045 | AEI-2011-105 | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Through the question of singular topologies in the Boulatov model, we
illustrate and summarize some of the recent advances in Group Field Theory.
| [
{
"created": "Tue, 13 Dec 2011 13:33:24 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Jun 2012 13:50:32 GMT",
"version": "v2"
}
] | 2012-06-29 | [
[
"Carrozza",
"Sylvain",
""
]
] | Through the question of singular topologies in the Boulatov model, we illustrate and summarize some of the recent advances in Group Field Theory. |
1608.05281 | Petr Tretyakov | Petr V. Tretyakov | Stability in higher-derivative matter fields theories | null | null | 10.1140/epjc/s10052-016-4355-7 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss possible instabilities in higher-derivative matter fields
theories. These theories has two free parameters $\beta_1$ and $\beta_4$. By
using dynamical system approach we explicitly demonstrate that for stability of
Minkowski space in expanding Universe it is need condition $\beta_4<0$. By
using quantum fie... | [
{
"created": "Thu, 18 Aug 2016 14:47:29 GMT",
"version": "v1"
}
] | 2016-10-12 | [
[
"Tretyakov",
"Petr V.",
""
]
] | We discuss possible instabilities in higher-derivative matter fields theories. These theories has two free parameters $\beta_1$ and $\beta_4$. By using dynamical system approach we explicitly demonstrate that for stability of Minkowski space in expanding Universe it is need condition $\beta_4<0$. By using quantum field... |
2404.10855 | Christopher Helmerich | Christopher Helmerich, Jared Fuchs, Alexey Bobrick, Brandon Melcher,
Luke Sellers, Gianni Martire | Warp Factory: A Numerical Toolkit for the Analysis and Optimization of
Warp Drive Geometries | 34 pages, 34 figures, Published in AIAA SCITECH 2023 Forum | null | 10.2514/6.2023-0553 | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | The last few decades of warp drive research have focused on analytic methods
to explore warp solutions to Einstein's field equations. These analytic
solutions tend to favor simple metric forms which are easier to analyze but
limit the space of exploration. In addition, all solutions to date have
involved unphysical q... | [
{
"created": "Tue, 16 Apr 2024 19:09:23 GMT",
"version": "v1"
}
] | 2024-04-18 | [
[
"Helmerich",
"Christopher",
""
],
[
"Fuchs",
"Jared",
""
],
[
"Bobrick",
"Alexey",
""
],
[
"Melcher",
"Brandon",
""
],
[
"Sellers",
"Luke",
""
],
[
"Martire",
"Gianni",
""
]
] | The last few decades of warp drive research have focused on analytic methods to explore warp solutions to Einstein's field equations. These analytic solutions tend to favor simple metric forms which are easier to analyze but limit the space of exploration. In addition, all solutions to date have involved unphysical qua... |
2206.12699 | Riccardo Della Monica | Riccardo Della Monica, Ivan de Martino, Mariafelicia de Laurentis | Constraining MOdified Gravity with the S2 Star | Proceeding of the conference Alternative Gravities and Fundamental
Cosmology (ALTECOSMOFUN'21) | Universe 2022, 8(2) | 10.3390/universe8020137 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have used publicly available kinematic data for the S2 star to constrain
the parameter space of MOdified Gravity. Integrating geodesics and using a
Markov Chain Monte Carlo algorithm we have provided with the first constraint
on the scales of the Galactic Centre for the parameter $\alpha$ of the theory,
which repr... | [
{
"created": "Sat, 25 Jun 2022 17:12:15 GMT",
"version": "v1"
}
] | 2022-06-28 | [
[
"Della Monica",
"Riccardo",
""
],
[
"de Martino",
"Ivan",
""
],
[
"de Laurentis",
"Mariafelicia",
""
]
] | We have used publicly available kinematic data for the S2 star to constrain the parameter space of MOdified Gravity. Integrating geodesics and using a Markov Chain Monte Carlo algorithm we have provided with the first constraint on the scales of the Galactic Centre for the parameter $\alpha$ of the theory, which repres... |
1507.02621 | Mir Faizal | Fay\c{c}al Hammad, Mir Faizal | A Logarithmic Correction in the Entropy Functional Formalism | 12 pages, 0 figures, Accepted for publication in Int. J. Mod. Phys. D | Int. J. Mod. Phys. D 25, 1650080 (2016) | 10.1142/S0218271816500802 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The entropy functional formalism allows one to recover general relativity,
modified gravity theories, as well as the Bekenstein-Hawking entropy formula.
In most approaches to quantum gravity, the Bekenstein-Hawking's entropy formula
acquires a logarithmic correction term. As such terms occur almost universally
in mos... | [
{
"created": "Mon, 6 Jul 2015 23:14:31 GMT",
"version": "v1"
},
{
"created": "Sat, 19 Dec 2015 17:29:55 GMT",
"version": "v2"
},
{
"created": "Sat, 16 Apr 2016 22:12:38 GMT",
"version": "v3"
}
] | 2016-06-24 | [
[
"Hammad",
"Fayçal",
""
],
[
"Faizal",
"Mir",
""
]
] | The entropy functional formalism allows one to recover general relativity, modified gravity theories, as well as the Bekenstein-Hawking entropy formula. In most approaches to quantum gravity, the Bekenstein-Hawking's entropy formula acquires a logarithmic correction term. As such terms occur almost universally in most ... |
1608.05249 | Xiao Zhang | Yaohua Wang, Xiao Zhang | Nonexistence of time-periodic solutions of the Dirac equation in
nonextreme Kerr-Newman-AdS spacetime | 13 pages, submitted | null | null | null | gr-qc math.CA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In non-extreme Kerr-Newman-AdS spacetime, we prove that there is no
nontrivial Dirac particle which is $L^p$ for $0<p\leq\frac{4}{3}$ with
arbitrary eigenvalue $\lambda$, and for $\frac{4}{3}<p\leq\frac{4}{3-2q}$,
$0<q<\frac{3}{2}$ with eigenvalue $|\lambda|>|Q|+q \kappa $, outside and away
from the event horizon. By... | [
{
"created": "Thu, 18 Aug 2016 12:09:39 GMT",
"version": "v1"
}
] | 2016-08-19 | [
[
"Wang",
"Yaohua",
""
],
[
"Zhang",
"Xiao",
""
]
] | In non-extreme Kerr-Newman-AdS spacetime, we prove that there is no nontrivial Dirac particle which is $L^p$ for $0<p\leq\frac{4}{3}$ with arbitrary eigenvalue $\lambda$, and for $\frac{4}{3}<p\leq\frac{4}{3-2q}$, $0<q<\frac{3}{2}$ with eigenvalue $|\lambda|>|Q|+q \kappa $, outside and away from the event horizon. By t... |
1903.01542 | Luca Buoninfante | Luca Buoninfante, Anupam Mazumdar | Nonlocal star as a blackhole mimicker | 12 pages. V2: references added, typos fixed. V3: accepted for
publication in PRD | Phys. Rev. D 100, 024031 (2019) | 10.1103/PhysRevD.100.024031 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of ghost-free, infinite derivative gravity, we will provide a
quantum mechanical framework in which we can describe astrophysical objects
devoid of curvature singularity and event horizon. In order to avoid ghosts and
singularity, the gravitational interaction has to be nonlocal, therefore, we
call the... | [
{
"created": "Mon, 4 Mar 2019 21:19:49 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Mar 2019 08:14:08 GMT",
"version": "v2"
},
{
"created": "Mon, 1 Jul 2019 07:58:19 GMT",
"version": "v3"
}
] | 2019-07-24 | [
[
"Buoninfante",
"Luca",
""
],
[
"Mazumdar",
"Anupam",
""
]
] | In the context of ghost-free, infinite derivative gravity, we will provide a quantum mechanical framework in which we can describe astrophysical objects devoid of curvature singularity and event horizon. In order to avoid ghosts and singularity, the gravitational interaction has to be nonlocal, therefore, we call these... |
gr-qc/9710116 | Haret Rosu | H.C. Rosu | Black holes and radiometry | 7pp | Mod.Phys.Lett. A8 (1993) 3429-3434 | 10.1142/S0217732393003846 | IFUG-R7-93 | gr-qc | null | Following Grischuk and Sidorov [Phys. Rev. D 42 (1990) 3413] in putting the
Bogolubov-Hawking coefficient of Schwarzschild black-holes in the squeezing
perspective, we provide a short discussion of Schwarzschild black holes as
radiometric standards
| [
{
"created": "Mon, 27 Oct 1997 22:46:46 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Rosu",
"H. C.",
""
]
] | Following Grischuk and Sidorov [Phys. Rev. D 42 (1990) 3413] in putting the Bogolubov-Hawking coefficient of Schwarzschild black-holes in the squeezing perspective, we provide a short discussion of Schwarzschild black holes as radiometric standards |
gr-qc/0303045 | Lars Andersson | Lars Andersson and Vincent Moncrief | Future complete vacuum spacetimes | 31 pages, latex, amsart | in '50 years of the Cauchy problem in General Relativity', eds.
Chrusciel and Friedrich, Birkhauser, Basel, 2004, pp. 299-330 | null | null | gr-qc | null | In this paper we prove a global existence theorem, in the direction of
cosmological expansion, for sufficiently small perturbations of a family of
spatially compact variants of the $k=-1$ Friedmann--Robertson--Walker vacuum
spacetime. We use a special gauge defined by constant mean curvature slicing
and a spatial har... | [
{
"created": "Tue, 11 Mar 2003 21:38:20 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Andersson",
"Lars",
""
],
[
"Moncrief",
"Vincent",
""
]
] | In this paper we prove a global existence theorem, in the direction of cosmological expansion, for sufficiently small perturbations of a family of spatially compact variants of the $k=-1$ Friedmann--Robertson--Walker vacuum spacetime. We use a special gauge defined by constant mean curvature slicing and a spatial harmo... |
gr-qc/0609130 | Yi Ling | Yi Ling, Song He and Hongbao Zhang | The kinematics of particles moving in rainbow spacetime | 5 pages | Mod.Phys.Lett.A22:2931-2938,2007 | 10.1142/S0217732307022980 | null | gr-qc | null | The kinematics of particles moving in rainbow spacetime is studied in this
paper. In particular the geodesics of a massive particle in rainbow flat
spacetime is obtained when the semi-classical effect of its own energy on the
background is taken into account. We show that in general the trajectory of a
freely falling... | [
{
"created": "Thu, 28 Sep 2006 01:11:36 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Ling",
"Yi",
""
],
[
"He",
"Song",
""
],
[
"Zhang",
"Hongbao",
""
]
] | The kinematics of particles moving in rainbow spacetime is studied in this paper. In particular the geodesics of a massive particle in rainbow flat spacetime is obtained when the semi-classical effect of its own energy on the background is taken into account. We show that in general the trajectory of a freely falling p... |
1805.10472 | Matsuno Satsuki | Hideki Ishihara, Satsuki Matsuno, Haruki Nakamura | Black holes submerged in Anti-de Sitter space | 33 page, 19 figures | null | null | OCU-PHYS-480 AP-GR-145 | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Suppose a one-dimensional isometry group acts on a space, we can consider a
submergion induced by the isometry, namely we obtain an orbit space by
identification of points on the orbit of the group action. We study the causal
structure of the orbit space for Anti-de Sitter space (AdS) explicitely. In the
case of AdS$... | [
{
"created": "Sat, 26 May 2018 12:46:37 GMT",
"version": "v1"
}
] | 2018-05-29 | [
[
"Ishihara",
"Hideki",
""
],
[
"Matsuno",
"Satsuki",
""
],
[
"Nakamura",
"Haruki",
""
]
] | Suppose a one-dimensional isometry group acts on a space, we can consider a submergion induced by the isometry, namely we obtain an orbit space by identification of points on the orbit of the group action. We study the causal structure of the orbit space for Anti-de Sitter space (AdS) explicitely. In the case of AdS$_3... |
2208.14768 | Subenoy Chakraborty | Ayanendu Dutta, Dhritimalya Roy, and Subenoy Chakraborty | The role of closed timelike curves in particle motion within Van Stockum
space-time: A generalization | null | Int. J. Mod. Phys. D 31 (13), 2250096 (2022) | 10.1142/S0218271822500961 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The present work analyses the particle motion in the Van Stockum space-time
considering the existence of closed timelike curves. Test particles with or
without angular momentum are studied in the present geometry. It is found that
only non-zero angular momentum test particles exist in the neighborhood of
closed timel... | [
{
"created": "Wed, 31 Aug 2022 10:53:15 GMT",
"version": "v1"
}
] | 2024-06-06 | [
[
"Dutta",
"Ayanendu",
""
],
[
"Roy",
"Dhritimalya",
""
],
[
"Chakraborty",
"Subenoy",
""
]
] | The present work analyses the particle motion in the Van Stockum space-time considering the existence of closed timelike curves. Test particles with or without angular momentum are studied in the present geometry. It is found that only non-zero angular momentum test particles exist in the neighborhood of closed timelik... |
gr-qc/9907047 | Vadim O. Ustiansky | A.V.Toporensky and V.O. Ustiansky | Dynamics of Bianchi IX universe with massive scalar field | 15 pages with 2 eps figures and 3 gif figures | null | null | null | gr-qc | null | The dynamics of the Bianchi IX cosmological model with minimally coupled
massive real scalar field is studied. The possibility of non-singular
transition from contraction to expansion is shown. A set of initial conditions
that lead to non-singular solutions is studied numerically.
| [
{
"created": "Tue, 13 Jul 1999 09:17:51 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Toporensky",
"A. V.",
""
],
[
"Ustiansky",
"V. O.",
""
]
] | The dynamics of the Bianchi IX cosmological model with minimally coupled massive real scalar field is studied. The possibility of non-singular transition from contraction to expansion is shown. A set of initial conditions that lead to non-singular solutions is studied numerically. |
2207.12155 | Alessandro Pesci | Alessandro Pesci | Information content and minimum-length metric: A drop of light | 40 pages, 1 figure, contribution to the special issue of GERG
dedicated to the memory of Prof. Thanu Padmanabhan | Gen. Rel. Grav. 54 (2022) 72 | 10.1007/s10714-022-02960-1 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the vast amount of results linking gravity with thermodynamics,
statistics, information, a path is described which tries to explore this
connection from the point of view of (non)locality of the gravitational field.
First the emphasis is put on that well-known thermodynamic results related to
null hypersurfaces (i... | [
{
"created": "Mon, 25 Jul 2022 12:56:16 GMT",
"version": "v1"
}
] | 2022-07-26 | [
[
"Pesci",
"Alessandro",
""
]
] | In the vast amount of results linking gravity with thermodynamics, statistics, information, a path is described which tries to explore this connection from the point of view of (non)locality of the gravitational field. First the emphasis is put on that well-known thermodynamic results related to null hypersurfaces (i.e... |
1411.1839 | Sudipta Das | Sudipta Das, Souvik Pramanik, Subir Ghosh | Effects of a Maximal Energy Scale in Thermodynamics for Photon Gas and
Construction of Path Integral | This is a review article based on our works arXiv:1002.0192,
arXiv:0908.0413, arXiv:1205.3919; v2: text overlap with gr-qc/0207085 removed | SIGMA 10 (2014), 104, 26 pages | 10.3842/SIGMA.2014.104 | null | gr-qc hep-th | http://creativecommons.org/licenses/by-nc-sa/3.0/ | In this article, we discuss some well-known theoretical models where an
observer-independent energy scale or a length scale is present. The presence of
this invariant scale necessarily deforms the Lorentz symmetry. We study
different aspects and features of such theories about how modifications arise
due to this cuto... | [
{
"created": "Fri, 7 Nov 2014 06:19:27 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Nov 2014 14:38:51 GMT",
"version": "v2"
}
] | 2014-11-14 | [
[
"Das",
"Sudipta",
""
],
[
"Pramanik",
"Souvik",
""
],
[
"Ghosh",
"Subir",
""
]
] | In this article, we discuss some well-known theoretical models where an observer-independent energy scale or a length scale is present. The presence of this invariant scale necessarily deforms the Lorentz symmetry. We study different aspects and features of such theories about how modifications arise due to this cutoff... |
gr-qc/9606048 | null | Mariano Cadoni | The dualities of 3D dilaton gravity | 15 pages, LaTex file, no figures | Phys.Rev.D54:7378-7385,1996 | 10.1103/PhysRevD.54.7378 | INFNCA-TH9610 | gr-qc hep-th | null | We investigate Brans-Dicke dilaton gravity theories in 2+1 dimensions. We
show that the reduced field equations for solutions with diagonal metric and
depending only on one spacetime coordinate have a continuous O(2) symmetry.
Using this symmetry we derive general static and cosmological solutions of the
theory. The ... | [
{
"created": "Mon, 17 Jun 1996 11:21:54 GMT",
"version": "v1"
}
] | 2011-09-09 | [
[
"Cadoni",
"Mariano",
""
]
] | We investigate Brans-Dicke dilaton gravity theories in 2+1 dimensions. We show that the reduced field equations for solutions with diagonal metric and depending only on one spacetime coordinate have a continuous O(2) symmetry. Using this symmetry we derive general static and cosmological solutions of the theory. The ac... |
1606.07173 | Francisco Frutos-Alfaro Dr. rer. nat. | Francisco Frutos-Alfaro and Michael Soffel | On Relativistic Multipole Moments of Stationary Spacetimes | null | Royal Society Open Science. 5: 180640, 2018 | 10.1098/rsos.180640 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Among the known exact solutions of Einstein vacuum field equations the
Manko-Novikov and the Quevedo-Mashhoon metrics might be suitable ones for the
description of the exterior gravitational field of some real non-collapsed
body. A new proposal to represent such exterior field is the stationary
q-metric. In this cont... | [
{
"created": "Thu, 23 Jun 2016 03:36:33 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Jul 2016 01:31:13 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Oct 2016 14:48:09 GMT",
"version": "v3"
},
{
"created": "Thu, 29 Nov 2018 20:17:03 GMT",
"version": "v4"
},
{
"cr... | 2019-09-17 | [
[
"Frutos-Alfaro",
"Francisco",
""
],
[
"Soffel",
"Michael",
""
]
] | Among the known exact solutions of Einstein vacuum field equations the Manko-Novikov and the Quevedo-Mashhoon metrics might be suitable ones for the description of the exterior gravitational field of some real non-collapsed body. A new proposal to represent such exterior field is the stationary q-metric. In this contri... |
2004.10503 | Teng Zhang | Teng Zhang, Denis Martynov, Andreas Freise, and Haixing Miao | Quantum Squeezing Schemes for Heterodyne Readout | null | Phys. Rev. D 101, 124052 (2020) | 10.1103/PhysRevD.101.124052 | null | gr-qc physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Advanced gravitational-wave detectors are limited by quantum noise in their
most sensitive frequency band. Quantum noise suppression techniques, such as
the application of the quantum squeezed state of light, have been actively
studied in the context of homodyne readouts. In this paper, we consider quantum
squeezing ... | [
{
"created": "Wed, 22 Apr 2020 11:34:37 GMT",
"version": "v1"
}
] | 2020-07-01 | [
[
"Zhang",
"Teng",
""
],
[
"Martynov",
"Denis",
""
],
[
"Freise",
"Andreas",
""
],
[
"Miao",
"Haixing",
""
]
] | Advanced gravitational-wave detectors are limited by quantum noise in their most sensitive frequency band. Quantum noise suppression techniques, such as the application of the quantum squeezed state of light, have been actively studied in the context of homodyne readouts. In this paper, we consider quantum squeezing sc... |
gr-qc/9911111 | John A. Gowan | John A. Gowan | A Spacetime Map of the Universe | 29 pages. Revision: conceptual restatement of spatial size of
universe in text | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A geometric spacetime map of the universe is presented, addressing problems
inherent in deep space observations and cosmology. Implications for the
observer's perspective, the cosmological "horizon" and "flatness" problem,
"inflation", and the recently observed accelerating expansion of the Universe
are discussed.
| [
{
"created": "Sat, 27 Nov 1999 18:38:22 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Apr 2009 13:30:07 GMT",
"version": "v10"
},
{
"created": "Wed, 1 Jul 2009 19:12:05 GMT",
"version": "v11"
},
{
"created": "Sun, 20 Nov 2011 22:22:47 GMT",
"version": "v12"
},
{
"... | 2011-11-22 | [
[
"Gowan",
"John A.",
""
]
] | A geometric spacetime map of the universe is presented, addressing problems inherent in deep space observations and cosmology. Implications for the observer's perspective, the cosmological "horizon" and "flatness" problem, "inflation", and the recently observed accelerating expansion of the Universe are discussed. |
1506.07049 | John Langford | Dean P. Foster and John Langford and Gabe Perez-Giz | Orbiting Radiation Stars | Updated draft | null | 10.1088/0264-9381/33/5/055002 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a numerical solution to Einstein's equation for a compact object
composed of null particles. The solution avoids quantum scale regimes and hence
neither relies upon nor ignores the interaction of quantum mechanics and
gravitation. The solution exhibits a deep gravitational well yet remains
singularity free. ... | [
{
"created": "Tue, 23 Jun 2015 15:28:56 GMT",
"version": "v1"
},
{
"created": "Sun, 20 Mar 2016 14:48:43 GMT",
"version": "v2"
}
] | 2016-03-22 | [
[
"Foster",
"Dean P.",
""
],
[
"Langford",
"John",
""
],
[
"Perez-Giz",
"Gabe",
""
]
] | We study a numerical solution to Einstein's equation for a compact object composed of null particles. The solution avoids quantum scale regimes and hence neither relies upon nor ignores the interaction of quantum mechanics and gravitation. The solution exhibits a deep gravitational well yet remains singularity free. In... |
1906.11550 | Naveena Kumara A | A. Naveena Kumara, C.L. Ahmed Rizwan, Deepak Vaid, K.M. Ajith | Critical Behaviour and Microscopic Structure of Charged AdS Black Hole
with a Global Monopole in Extended and Alternate Phase Spaces | 38 pages, 8 figures, comments are welcome! | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A detailed discussion on phase transition and microscopic structure of
charged AdS black hole with a global monopole is presented in both extended and
alternate phase spaces. In the analysis of critical behaviour, the classical
van der Waals analogy is drawn from isotherms which is followed by Gibbs free
energy study... | [
{
"created": "Thu, 27 Jun 2019 11:18:34 GMT",
"version": "v1"
},
{
"created": "Thu, 11 Jul 2019 15:46:44 GMT",
"version": "v2"
},
{
"created": "Mon, 6 Jan 2020 15:41:19 GMT",
"version": "v3"
}
] | 2020-01-07 | [
[
"Kumara",
"A. Naveena",
""
],
[
"Rizwan",
"C. L. Ahmed",
""
],
[
"Vaid",
"Deepak",
""
],
[
"Ajith",
"K. M.",
""
]
] | A detailed discussion on phase transition and microscopic structure of charged AdS black hole with a global monopole is presented in both extended and alternate phase spaces. In the analysis of critical behaviour, the classical van der Waals analogy is drawn from isotherms which is followed by Gibbs free energy study a... |
2308.16001 | Thanasis Giannakopoulos | Thanasis Giannakopoulos | Characteristic formulations of general relativity and applications | 179 pages, PhD Thesis, supplementary material at
https://github.com/ThanasisGiannakopoulos/PhD-thesis-supp | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | General relativity can describe various gravitational systems of
astrophysical relevance, like black holes and neutron stars, or even strongly
coupled systems through the holographic duality. The characteristic initial
(boundary) value problem has numerous applications in general relativity
involving numerical studie... | [
{
"created": "Wed, 30 Aug 2023 12:41:19 GMT",
"version": "v1"
}
] | 2023-08-31 | [
[
"Giannakopoulos",
"Thanasis",
""
]
] | General relativity can describe various gravitational systems of astrophysical relevance, like black holes and neutron stars, or even strongly coupled systems through the holographic duality. The characteristic initial (boundary) value problem has numerous applications in general relativity involving numerical studies ... |
2101.12196 | Kyriakos Destounis Dr. | Christoforos Vlachos, Eleftherios Papantonopoulos, Kyriakos Destounis | Echoes of Compact Objects in Scalar-Tensor Theories of Gravity | 15 pages + references, 7 figures, accepted for publication in PRD | Phys. Rev. D 103, 044042 (2021) | 10.1103/PhysRevD.103.044042 | null | gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | Scalar-tensor theory predicts solutions to the gravitational field equations
which describe compact objects in the presence of a non-minimally coupled
scalar field to the Einstein tensor. These objects are black holes with scalar
hair and wormholes supporting scalar phantom matter. The evolution of test
fields in fix... | [
{
"created": "Thu, 28 Jan 2021 18:56:02 GMT",
"version": "v1"
}
] | 2021-02-24 | [
[
"Vlachos",
"Christoforos",
""
],
[
"Papantonopoulos",
"Eleftherios",
""
],
[
"Destounis",
"Kyriakos",
""
]
] | Scalar-tensor theory predicts solutions to the gravitational field equations which describe compact objects in the presence of a non-minimally coupled scalar field to the Einstein tensor. These objects are black holes with scalar hair and wormholes supporting scalar phantom matter. The evolution of test fields in fixed... |
gr-qc/0304012 | Niklas Rohr | J. Mark Heinzle, N. Rohr, C. Uggla | Spherically symmetric relativistic stellar structures | 23 pages, 25 figures (compressed), LaTeX | Class.Quant.Grav. 20 (2003) 4567-4586 | 10.1088/0264-9381/20/21/004 | null | gr-qc astro-ph | null | We investigate relativistic spherically symmetric static perfect fluid models
in the framework of the theory of dynamical systems. The field equations are
recast into a regular dynamical system on a 3-dimensional compact state space,
thereby avoiding the non-regularity problems associated with the
Tolman-Oppenheimer-... | [
{
"created": "Wed, 2 Apr 2003 08:56:42 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Heinzle",
"J. Mark",
""
],
[
"Rohr",
"N.",
""
],
[
"Uggla",
"C.",
""
]
] | We investigate relativistic spherically symmetric static perfect fluid models in the framework of the theory of dynamical systems. The field equations are recast into a regular dynamical system on a 3-dimensional compact state space, thereby avoiding the non-regularity problems associated with the Tolman-Oppenheimer-Vo... |
gr-qc/0001068 | Sean A. Hayward | Sean A. Hayward | Gravitational waves from quasi-spherical black holes | 4 revtex pages, 2 eps figures | Phys.Rev.D61:101503,2000 | 10.1103/PhysRevD.61.101503 | null | gr-qc | null | A quasi-spherical approximation scheme, intended to apply to coalescing black
holes, allows the waveforms of gravitational radiation to be computed by
integrating ordinary differential equations.
| [
{
"created": "Fri, 21 Jan 2000 17:56:59 GMT",
"version": "v1"
}
] | 2009-12-30 | [
[
"Hayward",
"Sean A.",
""
]
] | A quasi-spherical approximation scheme, intended to apply to coalescing black holes, allows the waveforms of gravitational radiation to be computed by integrating ordinary differential equations. |
1606.04356 | Ramil Izmailov | Kamal K. Nandi, Alexander A. Potapov, Ramil Izmailov, Amarjit Tamang
and James C. Evans | Stability and instability of Ellis and phantom wormholes: Are there
ghosts? | 43 pages, 5 figures | Phys. Rev. D 93, 104044 (2016) | 10.1103/PhysRevD.93.104044 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is concluded in the literature that Ellis wormhole is unstable under small
perturbations and would decay either to the Schwarzschild black hole or expand
away to infinity. While this deterministic conclusion of instability is
correct, we show that the Ellis wormhole reduces to Schwarzschild black hole
\textit{only... | [
{
"created": "Mon, 6 Jun 2016 07:27:03 GMT",
"version": "v1"
}
] | 2016-06-22 | [
[
"Nandi",
"Kamal K.",
""
],
[
"Potapov",
"Alexander A.",
""
],
[
"Izmailov",
"Ramil",
""
],
[
"Tamang",
"Amarjit",
""
],
[
"Evans",
"James C.",
""
]
] | It is concluded in the literature that Ellis wormhole is unstable under small perturbations and would decay either to the Schwarzschild black hole or expand away to infinity. While this deterministic conclusion of instability is correct, we show that the Ellis wormhole reduces to Schwarzschild black hole \textit{only} ... |
1607.03689 | Matthew J. Lake Dr | Matthew J. Lake | Which quantum theory must be reconciled with gravity? (And what does it
mean for black holes?) | 38 pages, 5 figures. Invited contribution to the Universe special
issue "Open questions in black hole physics" (Gonzalo J. Olmo, Ed.). Matches
published version | Universe 2016, 2(4), 24 | 10.3390/universe2040024 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the nature of quantum properties in non-relativistic quantum
mechanics (QM) and relativistic QFTs, and examine the connection between formal
quantization schemes and intuitive notions of wave-particle duality. Based on
the map between classical Poisson brackets and their associated commutators,
such schem... | [
{
"created": "Wed, 13 Jul 2016 12:07:20 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Oct 2016 11:22:04 GMT",
"version": "v2"
}
] | 2016-10-21 | [
[
"Lake",
"Matthew J.",
""
]
] | We consider the nature of quantum properties in non-relativistic quantum mechanics (QM) and relativistic QFTs, and examine the connection between formal quantization schemes and intuitive notions of wave-particle duality. Based on the map between classical Poisson brackets and their associated commutators, such schemes... |
2112.01235 | Georgios Kraniotis | G. V. Kraniotis | Curvature Invariants for accelerating Kerr-Newman black holes in
(anti-)de Sitter spacetime | LaTeX file 48 pages, 22eps figures, v3 new results, figures added,v4
typo fixed, v5 version published in Classical and Quantum Gravity | Class.Quantum Grav. 39 (2022) 145002 | 10.1088/1361-6382/ac750a | null | gr-qc astro-ph.GA hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The curvature scalar invariants of the Riemann tensor are important in
General Relativity because they allow a manifestly coordinate invariant
characterisation of certain geometrical properties of spacetimes such as, among
others, curvature singularities, gravitomagnetism. We calculate explicit
analytic expressions f... | [
{
"created": "Thu, 2 Dec 2021 13:48:13 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Dec 2021 10:33:20 GMT",
"version": "v2"
},
{
"created": "Thu, 17 Feb 2022 17:26:05 GMT",
"version": "v3"
},
{
"created": "Thu, 24 Feb 2022 12:07:03 GMT",
"version": "v4"
},
{
"cr... | 2022-07-13 | [
[
"Kraniotis",
"G. V.",
""
]
] | The curvature scalar invariants of the Riemann tensor are important in General Relativity because they allow a manifestly coordinate invariant characterisation of certain geometrical properties of spacetimes such as, among others, curvature singularities, gravitomagnetism. We calculate explicit analytic expressions for... |
gr-qc/9611037 | Philip Mannheim | Philip D. Mannheim (University of Connecticut) | Classical Underpinnings of Gravitationally Induced Quantum Interference | LaTeX, 8 pages plus two figures in one postscript file | null | null | UCONN 96-08, October 1996 | gr-qc quant-ph | null | We show that the gravitational modification of the phase of a neutron beam
(the COW experiment) has a classical origin, being due to the time delay which
classical particles experience in traversing a background gravitational field.
Similarly, we show that classical light waves also undergo a phase shift in
traversin... | [
{
"created": "Wed, 13 Nov 1996 15:17:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mannheim",
"Philip D.",
"",
"University of Connecticut"
]
] | We show that the gravitational modification of the phase of a neutron beam (the COW experiment) has a classical origin, being due to the time delay which classical particles experience in traversing a background gravitational field. Similarly, we show that classical light waves also undergo a phase shift in traversing ... |
1402.5198 | J\"org Hennig | J\"org Hennig | Geometric relations for rotating and charged AdS black holes | 10 pages | Class. Quantum Grav. 31, 135005 (2014) | 10.1088/0264-9381/31/13/135005 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive mass-independent equations and inequalities for Kerr-Newman-anti-de
Sitter black holes. In particular, we obtain an equation that relates electric
charge, angular momentum and the areas of the event and Cauchy horizons. An
area-angular momentum-charge inequality is derived from this formula, which
becomes a... | [
{
"created": "Fri, 21 Feb 2014 03:44:09 GMT",
"version": "v1"
},
{
"created": "Mon, 16 Jun 2014 02:49:00 GMT",
"version": "v2"
}
] | 2014-06-17 | [
[
"Hennig",
"Jörg",
""
]
] | We derive mass-independent equations and inequalities for Kerr-Newman-anti-de Sitter black holes. In particular, we obtain an equation that relates electric charge, angular momentum and the areas of the event and Cauchy horizons. An area-angular momentum-charge inequality is derived from this formula, which becomes an ... |
2310.11827 | B. S. Ratanpal | Rinkal Patel and B. S. Ratanpal | A various equation of state for anisotropic models of compact star | 28 pages and 15 figures | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We obtain models of compact stars having pressure anisotropy on Finch-Skea
spacetime by considering generalized equation of state (EoS), whose particular
cases are linear, quadratic, polytropic, chaplygin and colour - flavor
locked(CFL) equation of states. The physical viability of models are tested for
strange star ... | [
{
"created": "Wed, 18 Oct 2023 09:28:16 GMT",
"version": "v1"
}
] | 2023-10-19 | [
[
"Patel",
"Rinkal",
""
],
[
"Ratanpal",
"B. S.",
""
]
] | We obtain models of compact stars having pressure anisotropy on Finch-Skea spacetime by considering generalized equation of state (EoS), whose particular cases are linear, quadratic, polytropic, chaplygin and colour - flavor locked(CFL) equation of states. The physical viability of models are tested for strange star ca... |
1908.04754 | Ayan Banerjee | Ayan Banerjee, Ksh. Newton Singh, M. K. Jasim and Farook Rahaman | Conformally symmetric traversable wormholes in $f(R,T)$ gravity | 10 pages and 9 figures, version published in Annals of Physics:
comments added and typos fixed | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | To find more deliberate $f(R, T)$ astrophysical solutions, we proceed by
studying wormhole geometries under the assumption of spherical symmetry and the
existence of a conformal Killing symmetry to attain the more acceptable
astrophysical results. To do this, we consider a more plausible and simple
model $f(R,T)=R+2\... | [
{
"created": "Sat, 10 Aug 2019 12:37:29 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Aug 2020 12:04:11 GMT",
"version": "v2"
}
] | 2020-08-21 | [
[
"Banerjee",
"Ayan",
""
],
[
"Singh",
"Ksh. Newton",
""
],
[
"Jasim",
"M. K.",
""
],
[
"Rahaman",
"Farook",
""
]
] | To find more deliberate $f(R, T)$ astrophysical solutions, we proceed by studying wormhole geometries under the assumption of spherical symmetry and the existence of a conformal Killing symmetry to attain the more acceptable astrophysical results. To do this, we consider a more plausible and simple model $f(R,T)=R+2\ch... |
0902.0346 | Matt Visser | Matt Visser (Victoria University of Wellington), Carlos Barcelo
(Astrophysics Institute of Andalusia), Stefano Liberati (SISSA and INFN,
Trieste), Sebastiano Sonego (University of Udine) | Small, dark, and heavy: But is it a black hole? | 17 pages, 8 figures. Technical seminar at the workshop "Black Holes
in General Relativity and String Theory", 24-30 August, 2008, Veli Losinj,
Croatia; V2: one reference added | PoS BHs,GRandStrings 2008:010,2008 | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Astronomers have certainly observed things that are small, dark, and heavy.
But are these objects really black holes in the sense of general relativity?
The consensus opinion is simply "yes", and there is very little "wriggle room".
We discuss one of the specific alternatives.
| [
{
"created": "Mon, 2 Feb 2009 19:51:07 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Feb 2009 20:55:15 GMT",
"version": "v2"
}
] | 2010-02-16 | [
[
"Visser",
"Matt",
"",
"Victoria University of Wellington"
],
[
"Barcelo",
"Carlos",
"",
"Astrophysics Institute of Andalusia"
],
[
"Liberati",
"Stefano",
"",
"SISSA and INFN,\n Trieste"
],
[
"Sonego",
"Sebastiano",
"",
"University of Udi... | Astronomers have certainly observed things that are small, dark, and heavy. But are these objects really black holes in the sense of general relativity? The consensus opinion is simply "yes", and there is very little "wriggle room". We discuss one of the specific alternatives. |
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