id stringlengths 9 13 | submitter stringlengths 1 64 ⌀ | authors stringlengths 5 22.9k | title stringlengths 4 245 | comments stringlengths 1 548 ⌀ | journal-ref stringlengths 4 362 ⌀ | doi stringlengths 12 82 ⌀ | report-no stringlengths 2 281 ⌀ | categories stringclasses 793 values | license stringclasses 9 values | orig_abstract stringlengths 24 1.95k | versions listlengths 1 30 | update_date stringlengths 10 10 | authors_parsed listlengths 1 1.74k | abstract stringlengths 21 1.95k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1708.08969 | Behrouz Mirza | Zahra Mirzaiyan, Behrouz Mirza, Elham Sharifian | Generating five-dimensional Myers-Perry black hole solution using
quaternions | 6 pages | Annals of Physics 389 (2018) 11-18 | 10.1016/j.aop.2017.12.005 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Newman-Janis and Giampieri algorithms are two simple methods to generate
stationary rotating black hole solutions in four dimensions. In this paper, we
obtain the Mayers-Perry black hole from the Schwartzchild solution in five
dimensions using quaternions. Our method generates the Mayers-Perry black hole
solution with two angular momenta in one fell swoop.
| [
{
"created": "Sat, 26 Aug 2017 09:25:08 GMT",
"version": "v1"
},
{
"created": "Wed, 10 Jan 2018 09:19:13 GMT",
"version": "v2"
}
] | 2018-01-11 | [
[
"Mirzaiyan",
"Zahra",
""
],
[
"Mirza",
"Behrouz",
""
],
[
"Sharifian",
"Elham",
""
]
] | The Newman-Janis and Giampieri algorithms are two simple methods to generate stationary rotating black hole solutions in four dimensions. In this paper, we obtain the Mayers-Perry black hole from the Schwartzchild solution in five dimensions using quaternions. Our method generates the Mayers-Perry black hole solution with two angular momenta in one fell swoop. |
0808.2623 | Natalia Kiriushcheva | N. Kiriushcheva, S.V. Kuzmin, C. Racknor, S.R. Valluri | Diffeomorphism Invariance in the Hamiltonian formulation of General
Relativity | 13 pages | Phys.Lett.A372:5101-5105,2008 | 10.1016/j.physleta.2008.05.081 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that when the Einstein-Hilbert Lagrangian is considered without
any non-covariant modifications or change of variables, its Hamiltonian
formulation leads to results consistent with principles of General Relativity.
The first-class constraints of such a Hamiltonian formulation, with the metric
tensor taken as a canonical variable, allow one to derive the generator of
gauge transformations, which directly leads to diffeomorphism invariance. The
given Hamiltonian formulation preserves general covariance of the
transformations derivable from it. This characteristic should be used as the
crucial consistency requirement that must be met by any Hamiltonian formulation
of General Relativity.
| [
{
"created": "Tue, 19 Aug 2008 15:33:21 GMT",
"version": "v1"
}
] | 2010-11-11 | [
[
"Kiriushcheva",
"N.",
""
],
[
"Kuzmin",
"S. V.",
""
],
[
"Racknor",
"C.",
""
],
[
"Valluri",
"S. R.",
""
]
] | It is shown that when the Einstein-Hilbert Lagrangian is considered without any non-covariant modifications or change of variables, its Hamiltonian formulation leads to results consistent with principles of General Relativity. The first-class constraints of such a Hamiltonian formulation, with the metric tensor taken as a canonical variable, allow one to derive the generator of gauge transformations, which directly leads to diffeomorphism invariance. The given Hamiltonian formulation preserves general covariance of the transformations derivable from it. This characteristic should be used as the crucial consistency requirement that must be met by any Hamiltonian formulation of General Relativity. |
gr-qc/9910104 | Martin Bojowald | Martin Bojowald | Loop Quantum Cosmology II: Volume Operators | 21 pages | Class.Quant.Grav.17:1509-1526,2000 | 10.1088/0264-9381/17/6/313 | PITHA 99/33 | gr-qc hep-th | null | Volume operators measuring the total volume of space in a loop quantum theory
of cosmological models are constructed. In the case of models with rotational
symmetry an investigation of the Higgs constraint imposed on the reduced
connection variables is necessary, a complete solution of which is given for
isotropic models; in this case the volume spectrum can be calculated
explicitly. It is observed that the stronger the symmetry conditions are the
smaller is the volume spectrum, which can be interpreted as level splitting due
to broken symmetries. Some implications for quantum cosmology are presented.
| [
{
"created": "Thu, 28 Oct 1999 16:07:09 GMT",
"version": "v1"
}
] | 2010-11-19 | [
[
"Bojowald",
"Martin",
""
]
] | Volume operators measuring the total volume of space in a loop quantum theory of cosmological models are constructed. In the case of models with rotational symmetry an investigation of the Higgs constraint imposed on the reduced connection variables is necessary, a complete solution of which is given for isotropic models; in this case the volume spectrum can be calculated explicitly. It is observed that the stronger the symmetry conditions are the smaller is the volume spectrum, which can be interpreted as level splitting due to broken symmetries. Some implications for quantum cosmology are presented. |
gr-qc/0506052 | Maurice H. P. M. van Putten | Maurice H.P.M. van Putten (MIT-LIGO) | Global spectral representations of black hole spacetimes in the complex
plane | Based on an invited talk at the Int'l Conf. Theor. Physics, 11-16
April 2005, Lebedev Physical Institute, Moscow | null | 10.1073/pnas.0508406103 | null | gr-qc hep-th | null | Binary black hole coalescence produces a finite burst of gravitational
radiation which propagates towards quiescent infinity. These spacetimes are
analytic about infinity and contain a dimensionless coupling constant $M/s$,
where $M$ denotes the total mass-energy and $s$ an imaginary distance. This
introduces globally convergent Fourier series on a complex radial coordinate,
allowing spectral representation of black hole spacetimes in all three
dimensions. We illustrate this representation theory on a Fourier-Legendre
expansion of Boyer-Lindquist initial data and a scalar wave equation with
signal recovery by Cauchy's integral formula.
| [
{
"created": "Thu, 9 Jun 2005 01:14:29 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"van Putten",
"Maurice H. P. M.",
"",
"MIT-LIGO"
]
] | Binary black hole coalescence produces a finite burst of gravitational radiation which propagates towards quiescent infinity. These spacetimes are analytic about infinity and contain a dimensionless coupling constant $M/s$, where $M$ denotes the total mass-energy and $s$ an imaginary distance. This introduces globally convergent Fourier series on a complex radial coordinate, allowing spectral representation of black hole spacetimes in all three dimensions. We illustrate this representation theory on a Fourier-Legendre expansion of Boyer-Lindquist initial data and a scalar wave equation with signal recovery by Cauchy's integral formula. |
gr-qc/0009029 | Romualdo Tresguerres | Antonio Pulido, Alfredo Tiemblo, Romualdo Tresguerres | Time evolution in the presence of gravity | PlainTeX file, 22 pgs., no figures | Gen.Rel.Grav.33:1495-1517,2001 | 10.1023/A:1012288826450 | null | gr-qc | null | We present a suggestion on the interpretation of canonical time evolution
when gravitation is present, based on the nonlinear gauge approach to gravity.
Essentially, our proposal consists of an internal-time concept, with the time
variable taken from the dynamical fields characteristic of the nonlinear
realization of the internal time-translational symmetry. Physical time
evolution requires the latter symmetry to be broken. After disregarding other
breaking mechanisms, we appeal to the Jordan-Brans-Dicke action, conveniently
interpreted, to achieve that goal. We show that nontrivial time evolution
follows, the special relativistic limit being recovered in the absence of
gravity.
| [
{
"created": "Mon, 11 Sep 2000 10:45:46 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Pulido",
"Antonio",
""
],
[
"Tiemblo",
"Alfredo",
""
],
[
"Tresguerres",
"Romualdo",
""
]
] | We present a suggestion on the interpretation of canonical time evolution when gravitation is present, based on the nonlinear gauge approach to gravity. Essentially, our proposal consists of an internal-time concept, with the time variable taken from the dynamical fields characteristic of the nonlinear realization of the internal time-translational symmetry. Physical time evolution requires the latter symmetry to be broken. After disregarding other breaking mechanisms, we appeal to the Jordan-Brans-Dicke action, conveniently interpreted, to achieve that goal. We show that nontrivial time evolution follows, the special relativistic limit being recovered in the absence of gravity. |
1609.03982 | Giacomo Rosati | Giovanni Amelino-Camelia, Leonardo Barcaroli, Giacomo D'Amico,
Niccol\'o Loret, Giacomo Rosati | Quantum-gravity-induced dual lensing and IceCube neutrinos | In this version V2 we give a definition of variation probability
which could be considered in alternative to the notion of variation
probability already introduced in version V1; both notions of variation
probability are contemplated in the data analysis. arXiv admin note: text
overlap with arXiv:1605.00496 | Int.J.Mod.Phys. D26 (2017) 1750076 | 10.1142/S0218271817500766 | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Momentum-space curvature, which is expected in some approaches to the
quantum-gravity problem, can produce dual redshift, a feature which introduces
energy dependence of the travel times of ultrarelativistic particles, and dual
lensing, a feature which mainly affects the direction of observation of
particles. In our recent arXiv:1605.00496 we explored the possibility that dual
redshift might be relevant in the analysis of IceCube neutrinos, obtaining
results which are preliminarily encouraging. Here we explore the possibility
that also dual lensing might play a role in the analysis of IceCube neutrinos.
In doing so we also investigate issues which are of broader interest, such as
the possibility of estimating the contribution by background neutrinos and some
noteworthy differences between candidate "early neutrinos" and candidate "late
neutrinos".
| [
{
"created": "Tue, 13 Sep 2016 19:04:58 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Sep 2016 00:00:14 GMT",
"version": "v2"
}
] | 2017-06-01 | [
[
"Amelino-Camelia",
"Giovanni",
""
],
[
"Barcaroli",
"Leonardo",
""
],
[
"D'Amico",
"Giacomo",
""
],
[
"Loret",
"Niccoló",
""
],
[
"Rosati",
"Giacomo",
""
]
] | Momentum-space curvature, which is expected in some approaches to the quantum-gravity problem, can produce dual redshift, a feature which introduces energy dependence of the travel times of ultrarelativistic particles, and dual lensing, a feature which mainly affects the direction of observation of particles. In our recent arXiv:1605.00496 we explored the possibility that dual redshift might be relevant in the analysis of IceCube neutrinos, obtaining results which are preliminarily encouraging. Here we explore the possibility that also dual lensing might play a role in the analysis of IceCube neutrinos. In doing so we also investigate issues which are of broader interest, such as the possibility of estimating the contribution by background neutrinos and some noteworthy differences between candidate "early neutrinos" and candidate "late neutrinos". |
1206.4720 | Matt Visser | Valentina Baccetti (Victoria University of Wellington), Prado
Martin-Moruno (Victoria University of Wellington), and Matt Visser (Victoria
University of Wellington) | Gordon and Kerr-Schild ansatze in massive and bimetric gravity | 22 pages | JHEP 1208 (2012) 108 | 10.1007/JHEP08(2012)108 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We develop the "generalized Gordon ansatz" for the ghost-free versions of
both massive and bimetric gravity, an ansatz which is general enough to include
almost all spacetimes commonly considered to be physically interesting, and
restricted enough to greatly simplify calculations. The ansatz allows explicit
calculation of the matrix square root gamma = sqrt{g^{-1} f} appearing as a
central feature of the ghost-free analysis. In particular, this ansatz
automatically allows us to write the effective stress-energy tensor as that
corresponding to a perfect fluid. A qualitatively similar "generalized
Kerr-Schild ansatz" can also be easily considered, now leading to an effective
stress-energy tensor that corresponds to a null fluid. Cosmological
implications are considered, as are consequences for black hole physics.
Finally we have a few words to say concerning the null energy condition in the
framework provided by these ansatze.
| [
{
"created": "Wed, 20 Jun 2012 21:00:21 GMT",
"version": "v1"
}
] | 2012-12-06 | [
[
"Baccetti",
"Valentina",
"",
"Victoria University of Wellington"
],
[
"Martin-Moruno",
"Prado",
"",
"Victoria University of Wellington"
],
[
"Visser",
"Matt",
"",
"Victoria\n University of Wellington"
]
] | We develop the "generalized Gordon ansatz" for the ghost-free versions of both massive and bimetric gravity, an ansatz which is general enough to include almost all spacetimes commonly considered to be physically interesting, and restricted enough to greatly simplify calculations. The ansatz allows explicit calculation of the matrix square root gamma = sqrt{g^{-1} f} appearing as a central feature of the ghost-free analysis. In particular, this ansatz automatically allows us to write the effective stress-energy tensor as that corresponding to a perfect fluid. A qualitatively similar "generalized Kerr-Schild ansatz" can also be easily considered, now leading to an effective stress-energy tensor that corresponds to a null fluid. Cosmological implications are considered, as are consequences for black hole physics. Finally we have a few words to say concerning the null energy condition in the framework provided by these ansatze. |
2010.04745 | Zack Carson | Zack Carson | Probing Fundamental Physics with Gravitational Waves | Ph.D. Thesis | University of Virginia, 2020 | 10.18130/v3-pxdw-2144 | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The explosive coalescence of two black holes 1.3 billion light years away has
for the very first time allowed us to peer into the extreme gravity region of
spacetime surrounding these events. With these maximally compact objects
reaching speeds up to 60% the speed of light, collision events such as these
create harsh spacetime environments where the fields are strong, non-linear,
and highly dynamical -- a place yet un-probed in human history. On September
14, 2015, the iconic chirp signal from such an event was registered
simultaneously by both of the Laser Interferometer Gravitational-Wave
Observatory (LIGO) detectors -- by an unparalleled feat of modern engineering.
Dubbed "GW150914", this gravitational wave event paved the way for an entirely
new observing window into the universe, providing for the unique opportunity to
probe fundamental physics from an entirely new viewpoint. Since this historic
event, the LIGO/Virgo collaboration (LVC) has further identified ten additional
gravitational wave signals in its first two observing runs, composed of a
myriad of different events. Important among these new cataloged detections is
GW170817, the first detection of gravitational waves from the merger of two
neutron stars, giving way to new insight into the supranuclear physics resident
within.
This thesis explores this new unique opportunity to harness the information
encoded within gravitational waves in regards to their source whence they came,
to probe fundamental physics from an entirely new perspective. Part A focuses
on probing nuclear physics by way of the tidal information encoded within
gravitational waves from binary neutron star mergers. Part B focuses on testing
general relativity from such events by way of the remnants of such spacetime
encoded within the gravitational wave signal.
| [
{
"created": "Fri, 9 Oct 2020 18:03:53 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Apr 2021 08:19:59 GMT",
"version": "v2"
}
] | 2021-04-27 | [
[
"Carson",
"Zack",
""
]
] | The explosive coalescence of two black holes 1.3 billion light years away has for the very first time allowed us to peer into the extreme gravity region of spacetime surrounding these events. With these maximally compact objects reaching speeds up to 60% the speed of light, collision events such as these create harsh spacetime environments where the fields are strong, non-linear, and highly dynamical -- a place yet un-probed in human history. On September 14, 2015, the iconic chirp signal from such an event was registered simultaneously by both of the Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors -- by an unparalleled feat of modern engineering. Dubbed "GW150914", this gravitational wave event paved the way for an entirely new observing window into the universe, providing for the unique opportunity to probe fundamental physics from an entirely new viewpoint. Since this historic event, the LIGO/Virgo collaboration (LVC) has further identified ten additional gravitational wave signals in its first two observing runs, composed of a myriad of different events. Important among these new cataloged detections is GW170817, the first detection of gravitational waves from the merger of two neutron stars, giving way to new insight into the supranuclear physics resident within. This thesis explores this new unique opportunity to harness the information encoded within gravitational waves in regards to their source whence they came, to probe fundamental physics from an entirely new perspective. Part A focuses on probing nuclear physics by way of the tidal information encoded within gravitational waves from binary neutron star mergers. Part B focuses on testing general relativity from such events by way of the remnants of such spacetime encoded within the gravitational wave signal. |
1812.08642 | Tapobrata Sarkar | Pritam Banerjee, Suvankar Paul, Rajibul Shaikh, Tapobrata Sarkar | Tidal effects away from the equatorial plane in Kerr backgrounds | Discussions improved. Some figures are slightly modified | null | 10.1016/j.physletb.2019.05.048 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study tidal effects on self-gravitating Newtonian stars rotating around a
Kerr black hole in stable circular orbits away from the equatorial plane. Such
cases are exemplified by a non-vanishing Carter's constant. Here, we calculate
the tidal disruption limit (Roche limit) of the star numerically, in Fermi
normal coordinates. The Roche limit is found to depend strongly on the choice
of the orbit, and differs significantly from the equatorial plane result as one
approaches nearly polar orbits. As expected, this difference is large when the
star is close to the black hole (near to the innermost stable circular orbit)
and becomes smaller when the star is far from it. We also discuss the
dependence of the Roche limit on the equation of state of the star, taking two
specific parameter values as examples.
| [
{
"created": "Thu, 20 Dec 2018 15:40:58 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Dec 2018 15:06:04 GMT",
"version": "v2"
},
{
"created": "Sat, 19 Jan 2019 07:06:53 GMT",
"version": "v3"
}
] | 2019-06-26 | [
[
"Banerjee",
"Pritam",
""
],
[
"Paul",
"Suvankar",
""
],
[
"Shaikh",
"Rajibul",
""
],
[
"Sarkar",
"Tapobrata",
""
]
] | We study tidal effects on self-gravitating Newtonian stars rotating around a Kerr black hole in stable circular orbits away from the equatorial plane. Such cases are exemplified by a non-vanishing Carter's constant. Here, we calculate the tidal disruption limit (Roche limit) of the star numerically, in Fermi normal coordinates. The Roche limit is found to depend strongly on the choice of the orbit, and differs significantly from the equatorial plane result as one approaches nearly polar orbits. As expected, this difference is large when the star is close to the black hole (near to the innermost stable circular orbit) and becomes smaller when the star is far from it. We also discuss the dependence of the Roche limit on the equation of state of the star, taking two specific parameter values as examples. |
1803.03615 | Nils A. Nilsson | Nils A. Nilsson and Ewa Czuchry | Ho\v{r}ava-Lifshitz cosmology in light of new data | Added comments and clarifications as per the referee's suggestions.
Accepted for publication in Physics of the Dark Universe | Physics of the Dark Universe 23C (2019) 100253 | 10.1016/j.dark.2018.100253 | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present new observational constraints on Lorentz violating
Ho\v{r}ava-Lifshitz cosmological scenarios using an updated cosmological data
set from Cosmic Microwave Background (Planck CMB), expansion rates of
elliptical and lenticular galaxies, JLA compilation (Joint Light-Curve
Analysis) data for Type Ia supernovae (SneIa), Baryon Acoustic Oscillations
(BAO) and priors on the Hubble parameter with an alternative parametrisation of
the equations. Unlike in other approaches we consider the curvature parameter
$\Omega_k$ as a free parameter in the analysis we considered the parameters
$\Omega_k$ and $\Delta N_\nu$ as completely free, which helped to place new,
updated bounds on several of the theory parameters. Remarkably, the detailed
balance scenario exhibits positive spatial curvature to more than 3$\sigma$,
whereas for further theory generalizations we found evidence for positive
spatial curvature at 1$\sigma$. This could create circumstantial evidence from
observations and could be used to single out distinct formulations and
scenarios.
| [
{
"created": "Fri, 9 Mar 2018 17:43:25 GMT",
"version": "v1"
},
{
"created": "Mon, 16 Apr 2018 10:11:46 GMT",
"version": "v2"
},
{
"created": "Fri, 28 Dec 2018 09:12:29 GMT",
"version": "v3"
}
] | 2018-12-31 | [
[
"Nilsson",
"Nils A.",
""
],
[
"Czuchry",
"Ewa",
""
]
] | We present new observational constraints on Lorentz violating Ho\v{r}ava-Lifshitz cosmological scenarios using an updated cosmological data set from Cosmic Microwave Background (Planck CMB), expansion rates of elliptical and lenticular galaxies, JLA compilation (Joint Light-Curve Analysis) data for Type Ia supernovae (SneIa), Baryon Acoustic Oscillations (BAO) and priors on the Hubble parameter with an alternative parametrisation of the equations. Unlike in other approaches we consider the curvature parameter $\Omega_k$ as a free parameter in the analysis we considered the parameters $\Omega_k$ and $\Delta N_\nu$ as completely free, which helped to place new, updated bounds on several of the theory parameters. Remarkably, the detailed balance scenario exhibits positive spatial curvature to more than 3$\sigma$, whereas for further theory generalizations we found evidence for positive spatial curvature at 1$\sigma$. This could create circumstantial evidence from observations and could be used to single out distinct formulations and scenarios. |
gr-qc/0606051 | Davide Batic | D. Batic | Scattering for massive Dirac fields on the Kerr metric | 33 pages, 1 figure, new proof of Lemma III.1, minor changes in
Section III, a few typos corrected in Thm. IV.1 and Thm. B.3 | J.Math.Phys.48:022502,2007 | 10.1063/1.2456345 | null | gr-qc | null | Starting with the Dirac equation outside the event horizon of a non-extreme
Kerr black hole, we develop a time-dependent scattering theory for massive
Dirac particles. The explicit computation of the modified wave operators at
infinity is done by implementing a time-dependent logarithmic phase shift from
the free dynamics to offset the long range term in the full Hamiltonian due to
the presence of the gravitational force. Analytical expressions for the wave
operators are also given.
| [
{
"created": "Mon, 12 Jun 2006 11:50:02 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jul 2006 07:43:54 GMT",
"version": "v2"
},
{
"created": "Wed, 20 Sep 2006 09:05:01 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Batic",
"D.",
""
]
] | Starting with the Dirac equation outside the event horizon of a non-extreme Kerr black hole, we develop a time-dependent scattering theory for massive Dirac particles. The explicit computation of the modified wave operators at infinity is done by implementing a time-dependent logarithmic phase shift from the free dynamics to offset the long range term in the full Hamiltonian due to the presence of the gravitational force. Analytical expressions for the wave operators are also given. |
2004.00086 | Maciej Dunajski | Peter Cameron, Maciej Dunajski | On Schwarzschild causality in higher dimensions | 34 pages, lots of figures. Final version, to appear in Classical and
Quantum Gravity | null | 10.1088/1361-6382/abb4b8 | null | gr-qc hep-th math.DG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that the causal properties of asymptotically flat spacetimes depend
on their dimensionality: while the time-like future of any point in the past
conformal infinity $\mathcal{I}^-$ contains the whole of the future conformal
infinity $\mathcal{I}^+$ in $(2+1)$ and $(3+1)$ dimensional Schwarzschild
spacetimes, this property (which we call the Penrose property) does not hold
for $(d+1)$ dimensional Schwarzschild if $d>3$. We also show that the Penrose
property holds for the Kerr solution in $(3+1)$ dimensions, and discuss the
connection with scattering theory in the presence of positive mass.
| [
{
"created": "Tue, 31 Mar 2020 20:09:53 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Sep 2020 09:02:47 GMT",
"version": "v2"
}
] | 2020-12-02 | [
[
"Cameron",
"Peter",
""
],
[
"Dunajski",
"Maciej",
""
]
] | We show that the causal properties of asymptotically flat spacetimes depend on their dimensionality: while the time-like future of any point in the past conformal infinity $\mathcal{I}^-$ contains the whole of the future conformal infinity $\mathcal{I}^+$ in $(2+1)$ and $(3+1)$ dimensional Schwarzschild spacetimes, this property (which we call the Penrose property) does not hold for $(d+1)$ dimensional Schwarzschild if $d>3$. We also show that the Penrose property holds for the Kerr solution in $(3+1)$ dimensions, and discuss the connection with scattering theory in the presence of positive mass. |
gr-qc/9902011 | Jorge Pullin | Jorge Pullin | Matters of Gravity, the newsletter of the APS Topical Group on
Gravitation | 18 pages, LaTeX with html.sty. Jorge Pullin (editor). PDF and html
versions (with figures) in http://vishnu.nirvana.phys.psu.edu/mog.html | null | null | MOG-13 | gr-qc | null | Contents:
Editorial
Correspondents
News:
- Topical Group News, by Jim Isenberg
- We hear that..., by Jorge Pullin
- The Chandra Satellite, by Beverly Berger
Research Briefs:
- Analytical event horizons of merging black holes, by Simonetta Frittelli
- LIGO project update, by David Shoemaker
- Bicentenary of the Cavendish Experiment, by Riley Newman
Conference reports:
- Eighth Midwest meeting, by Richard Hammond
- GWDAW 98, by Sam Finn
- Bad Honnef seminar, by Alan Randall.
| [
{
"created": "Wed, 3 Feb 1999 04:30:22 GMT",
"version": "v1"
}
] | 2009-03-10 | [
[
"Pullin",
"Jorge",
""
]
] | Contents: Editorial Correspondents News: - Topical Group News, by Jim Isenberg - We hear that..., by Jorge Pullin - The Chandra Satellite, by Beverly Berger Research Briefs: - Analytical event horizons of merging black holes, by Simonetta Frittelli - LIGO project update, by David Shoemaker - Bicentenary of the Cavendish Experiment, by Riley Newman Conference reports: - Eighth Midwest meeting, by Richard Hammond - GWDAW 98, by Sam Finn - Bad Honnef seminar, by Alan Randall. |
2103.16431 | Conrad Hewitt | C. G. Hewitt | Dynamical Equilibrium States of a Class of Irrotational Non-Orthogonally
Transitive $G_{2}$ Cosmologies I: The Conjecture of Chaotic Cosmological
Inhomogeneity | Only change is added reference to companion paper
arxiv.org:2103.16428 | null | 10.1088/1361-6382/ac0e46 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Einstein field equations for a class of irrotational non-orthogonally
transitive $G_{2}$ cosmologies are written down as a system of partial
differential equations. The equilibrium points are self-similar and can be
written as a one-parameter, five-dimensional, ordinary differential equation.
The corresponding cosmological models both evolve and have one-dimension of
inhomogeneity. The major mathematical features of this ordinary differential
equation are derived, and a cosmological interpretation is given. The
relationship to the exceptional Bianchi models is explained and exploited to
provide a conjecture about future generalizations.
| [
{
"created": "Tue, 30 Mar 2021 15:25:19 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Mar 2021 01:54:27 GMT",
"version": "v2"
}
] | 2021-09-01 | [
[
"Hewitt",
"C. G.",
""
]
] | The Einstein field equations for a class of irrotational non-orthogonally transitive $G_{2}$ cosmologies are written down as a system of partial differential equations. The equilibrium points are self-similar and can be written as a one-parameter, five-dimensional, ordinary differential equation. The corresponding cosmological models both evolve and have one-dimension of inhomogeneity. The major mathematical features of this ordinary differential equation are derived, and a cosmological interpretation is given. The relationship to the exceptional Bianchi models is explained and exploited to provide a conjecture about future generalizations. |
1901.09760 | Dongjin Chway | Dongjin Chway | Light Bending in Models with a Generic Scalar Field | 17 pages, no figure; v2: minor changes; more references are added in
the introduction | null | null | CTPU-PTC-19-02 | gr-qc hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the deflection and time delay of light by the Sun in general scalar
extensions of the Standard Model which may violate the equivalence principle.
Despite the presence of the interaction $\phi FF$ or $\phi F \tilde{F}$ between
the scalar field and photon, we show that the bending and time delay of light
are the same as in Einstein's general relativity. The bending angle is obtained
using geometrical optics and compared with the angle obtained using another
method based on scattering amplitude. It is pointed out that the method based
on scattering amplitude can lead to wrong conclusions about potential energy
and light polarization. Also, we obtain a constraint on the generic scalar
particle from the parametrized post-Newtonian parameter $\gamma$, noting that
planet motions are affected by the scalar field as in scalar-tensor theories
with some modifications to the scalar field's couplings to the Sun and planets.
| [
{
"created": "Mon, 28 Jan 2019 16:05:49 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Feb 2019 14:06:09 GMT",
"version": "v2"
}
] | 2019-02-14 | [
[
"Chway",
"Dongjin",
""
]
] | We study the deflection and time delay of light by the Sun in general scalar extensions of the Standard Model which may violate the equivalence principle. Despite the presence of the interaction $\phi FF$ or $\phi F \tilde{F}$ between the scalar field and photon, we show that the bending and time delay of light are the same as in Einstein's general relativity. The bending angle is obtained using geometrical optics and compared with the angle obtained using another method based on scattering amplitude. It is pointed out that the method based on scattering amplitude can lead to wrong conclusions about potential energy and light polarization. Also, we obtain a constraint on the generic scalar particle from the parametrized post-Newtonian parameter $\gamma$, noting that planet motions are affected by the scalar field as in scalar-tensor theories with some modifications to the scalar field's couplings to the Sun and planets. |
2103.10649 | Hideki Asada | Keita Takizawa, Hideki Asada | Iterative solutions for the gravitational lens equation in the strong
deflection limit | 9 pages, 6 figures, correcting a numerical value and a sentence in
the introduction section, PRD in press | Phys. Rev. D 103, 104039 (2021) | 10.1103/PhysRevD.103.104039 | null | gr-qc astro-ph.CO hep-th | http://creativecommons.org/licenses/by/4.0/ | Two exact lens equations have been recently shown to be equivalent to each
other, being consistent with the gravitational deflection angle of light from a
source to an observer, both of which can be within a finite distance from a
lens object [Phys. Rev. D 102, 064060 (2020)]. We examine methods for iterative
solutions of the gravitational lens equations in the strong deflection limit.
It has been so far unclear whether a convergent series expansion can be
provided by the gravitational lens approach based on the geometrical optics for
obtaining approximate solutions in the strong deflection limit in terms of a
small offset angle. By using the ratio of the lens mass to the lens distance,
we discuss a slightly different method for iterative solutions and the behavior
of the convergence. Finite distance effects begin at the third order in the
iterative method. The iterative solutions in the strong deflection limit are
estimated for Sgr $A^{*}$ and M87. These results suggest that only the linear
order solution can be relevant with current observations, while the finite
distance effects at the third order may be negligible in the Schwarzschild lens
model for these astronomical objects.
| [
{
"created": "Fri, 19 Mar 2021 06:09:57 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Apr 2021 07:47:59 GMT",
"version": "v2"
},
{
"created": "Wed, 12 May 2021 00:45:09 GMT",
"version": "v3"
}
] | 2021-05-26 | [
[
"Takizawa",
"Keita",
""
],
[
"Asada",
"Hideki",
""
]
] | Two exact lens equations have been recently shown to be equivalent to each other, being consistent with the gravitational deflection angle of light from a source to an observer, both of which can be within a finite distance from a lens object [Phys. Rev. D 102, 064060 (2020)]. We examine methods for iterative solutions of the gravitational lens equations in the strong deflection limit. It has been so far unclear whether a convergent series expansion can be provided by the gravitational lens approach based on the geometrical optics for obtaining approximate solutions in the strong deflection limit in terms of a small offset angle. By using the ratio of the lens mass to the lens distance, we discuss a slightly different method for iterative solutions and the behavior of the convergence. Finite distance effects begin at the third order in the iterative method. The iterative solutions in the strong deflection limit are estimated for Sgr $A^{*}$ and M87. These results suggest that only the linear order solution can be relevant with current observations, while the finite distance effects at the third order may be negligible in the Schwarzschild lens model for these astronomical objects. |
1905.01742 | Roberto Giamb\`o | Roberto Giamb\`o, John Miritzis, Annagiulia Pezzola | Late time evolution of negatively curved FLRW models | accepted version for publication | Eur. Phys. J. Plus (2020) 135:367 | 10.1140/epjp/s13360-020-00370-3 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the late time evolution of negatively curved
Friedmann--Le\-ma\^{\i}tre--Robert\-son--Walker (FLRW) models with a perfect
fluid matter source and a scalar field nonminimally coupled to matter. Since,
under mild assumptions on the potential $V$, it is already known that
equilibria corresponding to non-negative local minima for $V$ are
asymptotically stable, we classify all cases where one of the energy components
eventually dominates. In particular for nondegenerate minima with zero critical
value, we rigorously prove that if $\gamma$, the parameter of the equation of
state is larger than $2/3$, then there is a transfer of energy from the fluid
and the scalar field to the energy density of the scalar curvature. Thus, the
scalar curvature, if present, has a dominant effect on the late evolution of
the universe and eventually dominates over both the perfect fluid and the
scalar field. The analysis in complemented with the case where $V$ is
exponential and therefore the scalar field diverges to infinity.
| [
{
"created": "Sun, 5 May 2019 20:11:39 GMT",
"version": "v1"
},
{
"created": "Mon, 23 Sep 2019 16:12:32 GMT",
"version": "v2"
},
{
"created": "Thu, 23 Apr 2020 10:09:35 GMT",
"version": "v3"
}
] | 2020-04-24 | [
[
"Giambò",
"Roberto",
""
],
[
"Miritzis",
"John",
""
],
[
"Pezzola",
"Annagiulia",
""
]
] | We study the late time evolution of negatively curved Friedmann--Le\-ma\^{\i}tre--Robert\-son--Walker (FLRW) models with a perfect fluid matter source and a scalar field nonminimally coupled to matter. Since, under mild assumptions on the potential $V$, it is already known that equilibria corresponding to non-negative local minima for $V$ are asymptotically stable, we classify all cases where one of the energy components eventually dominates. In particular for nondegenerate minima with zero critical value, we rigorously prove that if $\gamma$, the parameter of the equation of state is larger than $2/3$, then there is a transfer of energy from the fluid and the scalar field to the energy density of the scalar curvature. Thus, the scalar curvature, if present, has a dominant effect on the late evolution of the universe and eventually dominates over both the perfect fluid and the scalar field. The analysis in complemented with the case where $V$ is exponential and therefore the scalar field diverges to infinity. |
2105.15184 | Marco Antonelli | Lorenzo Gavassino and Marco Antonelli | Unified Extended Irreversible Thermodynamics and the stability of
relativistic theories for dissipation | 30 pages, 3 figures. This review article is part of the special issue
"Neutron Star Physics in the Multi-Messenger Discourse" for Frontiers
Astronomy and Space Science, see
https://www.frontiersin.org/articles/10.3389/fspas.2021.686344/abstract | Front. Astron. Space Sci. 8:686344 (2021) | 10.3389/fspas.2021.686344 | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a relativistic context, the main purpose of Extended Irreversible
Thermodynamics (EIT) is to generalize the principles of non-equilibrium
thermodynamics to the domain of fluid dynamics. In particular, the theory aims
at modelling any diffusion-type process (like heat as diffusion of energy,
viscosity as diffusion of momentum, charge-conductivity as diffusion of
particles) directly from thermodynamic laws. Although in Newtonian physics this
task can be achieved with a first-order approach to dissipation (i.e.
Navier-Stokes-Fourier like equations), in a relativistic framework the
relativity of simultaneity poses serious challenges to the first-order
methodology, originating instabilities which are, instead, naturally eliminated
within EIT. The first part of this work is dedicated to reviewing the most
recent progress made in understanding the mathematical origin of this
instability problem. In the second part, we present the formalism that arises
by promoting non-equilibrium thermodynamics to a classical effective field
theory. We call this approach Unified Extended Irreversible Thermodynamics
(UEIT), because it contains, as particular cases, EIT itself, in particular the
Israel-Stewart theory and the divergence-type theories, plus Carter's approach
and most branches of non-equilibrium thermodynamics, such as relativistic
chemistry and radiation hydrodynamics. We use this formalism to explain why all
these theories are stable by construction (provided that the microscopic input
is correct), showing that their (Lyapunov) stability is a direct consequence of
the second law of thermodynamics.
| [
{
"created": "Mon, 31 May 2021 17:46:29 GMT",
"version": "v1"
}
] | 2021-06-01 | [
[
"Gavassino",
"Lorenzo",
""
],
[
"Antonelli",
"Marco",
""
]
] | In a relativistic context, the main purpose of Extended Irreversible Thermodynamics (EIT) is to generalize the principles of non-equilibrium thermodynamics to the domain of fluid dynamics. In particular, the theory aims at modelling any diffusion-type process (like heat as diffusion of energy, viscosity as diffusion of momentum, charge-conductivity as diffusion of particles) directly from thermodynamic laws. Although in Newtonian physics this task can be achieved with a first-order approach to dissipation (i.e. Navier-Stokes-Fourier like equations), in a relativistic framework the relativity of simultaneity poses serious challenges to the first-order methodology, originating instabilities which are, instead, naturally eliminated within EIT. The first part of this work is dedicated to reviewing the most recent progress made in understanding the mathematical origin of this instability problem. In the second part, we present the formalism that arises by promoting non-equilibrium thermodynamics to a classical effective field theory. We call this approach Unified Extended Irreversible Thermodynamics (UEIT), because it contains, as particular cases, EIT itself, in particular the Israel-Stewart theory and the divergence-type theories, plus Carter's approach and most branches of non-equilibrium thermodynamics, such as relativistic chemistry and radiation hydrodynamics. We use this formalism to explain why all these theories are stable by construction (provided that the microscopic input is correct), showing that their (Lyapunov) stability is a direct consequence of the second law of thermodynamics. |
2210.01372 | Ayan Banerjee | Takol Tangphati, Ayan Banerjee, Sudan Hansraj and Anirudh Pradhan | The criteria of the anisotropic quark star models in Rastall gravity | 9 pages, 5 figures | null | 10.1016/j.aop.2023.169285 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Quark stars are terrestrial laboratories to study fundamental physics at
ultrahigh densities and temperatures. In this work, we investigate the internal
structure and the physical properties of quark stars (QSs) in the Rastall
gravity. Rastall gravity is considered a non-conservative theory of gravity,
which is an effective gravity theory at high energy density, e.g., relevant to
the early universe and dense, compact objects. We derive the hydrostatic
equilibrium structure for QSs with the inclusion of anisotropic pressure. More
specifically, we find the QS mass-radius relations for the MIT bag model. We
focus on the model depending on the Rastall free parameter $\eta$ and examine
the deviations from the General Relativity (GR) counterparts.
| [
{
"created": "Tue, 4 Oct 2022 04:28:47 GMT",
"version": "v1"
}
] | 2023-04-26 | [
[
"Tangphati",
"Takol",
""
],
[
"Banerjee",
"Ayan",
""
],
[
"Hansraj",
"Sudan",
""
],
[
"Pradhan",
"Anirudh",
""
]
] | Quark stars are terrestrial laboratories to study fundamental physics at ultrahigh densities and temperatures. In this work, we investigate the internal structure and the physical properties of quark stars (QSs) in the Rastall gravity. Rastall gravity is considered a non-conservative theory of gravity, which is an effective gravity theory at high energy density, e.g., relevant to the early universe and dense, compact objects. We derive the hydrostatic equilibrium structure for QSs with the inclusion of anisotropic pressure. More specifically, we find the QS mass-radius relations for the MIT bag model. We focus on the model depending on the Rastall free parameter $\eta$ and examine the deviations from the General Relativity (GR) counterparts. |
gr-qc/0309091 | Vladimir S. Manko | V.S. Manko, E. Ruiz | On the discrepancy between two approaches to the equilibrium problem for
spinning particles | 9 pages; to appear in Gravitation & Cosmology | Grav.Cosmol. 9 (2003) 183-185 | null | null | gr-qc | null | We show that the absence of equilibrium states of two uncharged spinning
particles located on the symmetry axis, revealed in an approximate approach
recently employed by Bonnor, can be explained by a non-general character of his
approximation scheme which lacks an important arbitrary parameter representing
a strut. The absence of this parameter introduces an artificial restriction on
the particles' angular momenta, making it impossible to find a physical
solution to the balance equations.
| [
{
"created": "Fri, 19 Sep 2003 00:25:51 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Manko",
"V. S.",
""
],
[
"Ruiz",
"E.",
""
]
] | We show that the absence of equilibrium states of two uncharged spinning particles located on the symmetry axis, revealed in an approximate approach recently employed by Bonnor, can be explained by a non-general character of his approximation scheme which lacks an important arbitrary parameter representing a strut. The absence of this parameter introduces an artificial restriction on the particles' angular momenta, making it impossible to find a physical solution to the balance equations. |
1911.13199 | Enrique Gaztanaga | Enrique Gaztanaga | Homogeneity and the causal boundary | 10 pages, 2 figures, invited review at XXXIX Polish Astronomical
Society Meeting. arXiv admin note: text overlap with arXiv:1904.08218 | Contribution to the Proceedings of the XXXIX Polish Astronomical
(09-12 September 2019, Olsztyn, Poland) | null | null | gr-qc astro-ph.CO hep-th physics.hist-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A Universe with finite age also has a finite causal scale $\chi_\S$, so the
metric can not be homogeneous for $\chi>\chi_\S$, as it is usually assumed. To
account for this, we propose a new causal boundary condition, that can be
fulfil by fixing the cosmological constant $\Lambda$ (a free parameter for
gravity). The resulting Universe is inhomogeneous, with possible variation of
cosmological parameters on scales $\chi \simeq \chi_\S$. The size of $\chi_\S$
depends on the details of inflation, but regardless of its size, the boundary
condition forces $\Lambda/8\pi G $ to cancel the contribution of a constant
vacuum energy $\rho_{vac}$ to the measured $\rho_\Lambda \equiv \Lambda/8\pi G
+ \rho_{vac}$. To reproduce the observed $\rho_{\Lambda} \simeq 2 \rho_m$ today
with $\chi_\S \rightarrow \infty$ we then need a universe filled with evolving
dark energy (DE) with pressure $p_{DE}> - \rho_{DE}$ and a fine tuned value of
$\rho_{DE} \simeq 2 \rho_m$ today. This seems very odd, but there is another
solution to this puzzle. We can have a finite value of $\chi_\S \simeq 3 c/H_0$
without the need of DE. This scale corresponds to half the sky at $z \sim 1$
and 60deg at $z \sim 1000$, which is consistent with the anomalous lack of
correlations observed in the CMB.
| [
{
"created": "Tue, 26 Nov 2019 15:33:54 GMT",
"version": "v1"
}
] | 2019-12-03 | [
[
"Gaztanaga",
"Enrique",
""
]
] | A Universe with finite age also has a finite causal scale $\chi_\S$, so the metric can not be homogeneous for $\chi>\chi_\S$, as it is usually assumed. To account for this, we propose a new causal boundary condition, that can be fulfil by fixing the cosmological constant $\Lambda$ (a free parameter for gravity). The resulting Universe is inhomogeneous, with possible variation of cosmological parameters on scales $\chi \simeq \chi_\S$. The size of $\chi_\S$ depends on the details of inflation, but regardless of its size, the boundary condition forces $\Lambda/8\pi G $ to cancel the contribution of a constant vacuum energy $\rho_{vac}$ to the measured $\rho_\Lambda \equiv \Lambda/8\pi G + \rho_{vac}$. To reproduce the observed $\rho_{\Lambda} \simeq 2 \rho_m$ today with $\chi_\S \rightarrow \infty$ we then need a universe filled with evolving dark energy (DE) with pressure $p_{DE}> - \rho_{DE}$ and a fine tuned value of $\rho_{DE} \simeq 2 \rho_m$ today. This seems very odd, but there is another solution to this puzzle. We can have a finite value of $\chi_\S \simeq 3 c/H_0$ without the need of DE. This scale corresponds to half the sky at $z \sim 1$ and 60deg at $z \sim 1000$, which is consistent with the anomalous lack of correlations observed in the CMB. |
1803.05312 | Sankhasubhra Nag | Nandan Roy, Shivani Singh, Sankhasubhra Nag, and Tapas K. Das | Second Order Perturbative Effects on the Acoustic Geometry | Latex 2e, 9 pages | null | null | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we have studied the effect of higher order perturbations,
particularly the second order in details, on the sonic horizon. We have
considered two different schemes of perturbations which are velocity potential
perturbation and mass acceleration rate perturbation. These two schemes give us
qualitatively similar behaviour. We have found that the analogue gravity
formalism also holds for the higher order perturbations.
| [
{
"created": "Mon, 12 Mar 2018 18:49:22 GMT",
"version": "v1"
}
] | 2018-03-15 | [
[
"Roy",
"Nandan",
""
],
[
"Singh",
"Shivani",
""
],
[
"Nag",
"Sankhasubhra",
""
],
[
"Das",
"Tapas K.",
""
]
] | In this work, we have studied the effect of higher order perturbations, particularly the second order in details, on the sonic horizon. We have considered two different schemes of perturbations which are velocity potential perturbation and mass acceleration rate perturbation. These two schemes give us qualitatively similar behaviour. We have found that the analogue gravity formalism also holds for the higher order perturbations. |
gr-qc/0205039 | Luca Lusanna | Luca Lusanna (INFN, Firenze) | Spacetime, General Covariance, Dirac-Bergmann Observables and
Non-Inertial Frames | 23 pages | null | 10.1142/9789812791368_0005 | null | gr-qc astro-ph hep-th | null | Talk at the 25th Johns Hopkins Workshop "2001: A Relativistic Spacetime
Odyssey", Firenze September 2001.
| [
{
"created": "Fri, 10 May 2002 08:30:28 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Lusanna",
"Luca",
"",
"INFN, Firenze"
]
] | Talk at the 25th Johns Hopkins Workshop "2001: A Relativistic Spacetime Odyssey", Firenze September 2001. |
gr-qc/0006032 | Paolo Matteucci | Marco Godina, Paolo Matteucci and James A. Vickers | Metric-affine gravity and the Nester-Witten 2-form | LaTeX (14 pages, 3 runs); added references, corrected typos,
clarified content of section 3 | J.Geom.Phys. 39 (2001) 265-275 | 10.1016/S0393-0440(01)00007-9 | null | gr-qc | null | In this paper we redefine the well-known metric-affine Hilbert Lagrangian in
terms of a spin-connection and a spin-tetrad. On applying the Poincar\'e-Cartan
method and using the geometry of gauge-natural bundles, a global gravitational
superpotential is derived. On specializing to the case of the Kosmann lift, we
recover the result originally found by Kijowski (1978) for the metric (natural)
Hilbert Lagrangian. On choosing a different, suitable lift, we can also recover
the Nester-Witten 2-form, which plays an important role in the energy
positivity proof and in many quasi-local definitions of mass.
| [
{
"created": "Fri, 9 Jun 2000 14:03:26 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Sep 2001 14:14:24 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Godina",
"Marco",
""
],
[
"Matteucci",
"Paolo",
""
],
[
"Vickers",
"James A.",
""
]
] | In this paper we redefine the well-known metric-affine Hilbert Lagrangian in terms of a spin-connection and a spin-tetrad. On applying the Poincar\'e-Cartan method and using the geometry of gauge-natural bundles, a global gravitational superpotential is derived. On specializing to the case of the Kosmann lift, we recover the result originally found by Kijowski (1978) for the metric (natural) Hilbert Lagrangian. On choosing a different, suitable lift, we can also recover the Nester-Witten 2-form, which plays an important role in the energy positivity proof and in many quasi-local definitions of mass. |
1506.05597 | Xiangdong Zhang | Xiangdong Zhang | Higher dimensional Loop Quantum Cosmology | 14 pages. Minor revision and references added, presentation improved | Eur. Phys. J. C (2016) 76: 395 | 10.1140/epjc/s10052-016-4249-8 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Loop quantum cosmology(LQC) is the symmetric model of loop quantum gravity.
In this paper, we generalize the structure of loop quantum cosmology to the
theories with arbitrary spacetime dimensions. The isotropic and homogenous
cosmological model in n+1 dimensions is quantized by the loop quantization
method. Interestingly, we find that the underlying quantum theories are divided
into two qualitatively different sectors according to spacetime dimensions. The
effective Hamiltonian and modified dynamical equations of n+1 dimensional LQC
are obtained. Moreover, our results indicate that the classical big bang
singularity is resolved in arbitrary spacetime dimensions by a quantum bounce.
We also briefly discuss the similarities and differences between the n+1
dimensional model and the 3+1 dimensional one. Our model serves as a first
example of higher dimensional loop quantum cosmology and offers possibility to
investigate quantum gravity effects in higher dimensional cosmology.
| [
{
"created": "Thu, 18 Jun 2015 09:27:59 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jun 2015 15:49:12 GMT",
"version": "v2"
},
{
"created": "Wed, 23 Sep 2015 20:01:25 GMT",
"version": "v3"
},
{
"created": "Tue, 6 Oct 2015 13:52:48 GMT",
"version": "v4"
}
] | 2016-10-13 | [
[
"Zhang",
"Xiangdong",
""
]
] | Loop quantum cosmology(LQC) is the symmetric model of loop quantum gravity. In this paper, we generalize the structure of loop quantum cosmology to the theories with arbitrary spacetime dimensions. The isotropic and homogenous cosmological model in n+1 dimensions is quantized by the loop quantization method. Interestingly, we find that the underlying quantum theories are divided into two qualitatively different sectors according to spacetime dimensions. The effective Hamiltonian and modified dynamical equations of n+1 dimensional LQC are obtained. Moreover, our results indicate that the classical big bang singularity is resolved in arbitrary spacetime dimensions by a quantum bounce. We also briefly discuss the similarities and differences between the n+1 dimensional model and the 3+1 dimensional one. Our model serves as a first example of higher dimensional loop quantum cosmology and offers possibility to investigate quantum gravity effects in higher dimensional cosmology. |
gr-qc/0006095 | Michele Vallisneri | Massimo Pauri and Michele Vallisneri | Marzke-Wheeler coordinates for accelerated observers in special
relativity | AmsLaTeX, 22 pages, 8 eps figures; revised, references added. To
appear in Foundations of Physics Letters, October 2000 | Found.Phys.Lett. 13 (2000) 401-425 | null | null | gr-qc hep-th | null | In special relativity, the definition of coordinate systems adapted to
generic accelerated observers is a long-standing problem, which has found
unequivocal solutions only for the simplest motions. We show that the
Marzke-Wheeler construction, an extension of the Einstein synchronization
convention, produces accelerated systems of coordinates with desirable
properties: (a) they reduce to Lorentz coordinates in a neighborhood of the
observers' world-lines; (b) they index continuously and completely the causal
envelope of the world-line (that is, the intersection of its causal past and
its causal future: for well-behaved world-lines, the entire space-time). In
particular, Marzke-Wheeler coordinates provide a smooth and consistent
foliation of the causal envelope of any accelerated observer into space-like
surfaces.
We compare the Marzke-Wheeler procedure with other definitions of accelerated
coordinates; we examine it in the special case of stationary motions, and we
provide explicit coordinate transformations for uniformly accelerated and
uniformly rotating observers. Finally, we employ the notion of Marzke-Wheeler
simultaneity to clarify the relativistic paradox of the twins, by pinpointing
the local origin of differential aging.
| [
{
"created": "Wed, 28 Jun 2000 07:53:07 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Sep 2000 07:49:47 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Pauri",
"Massimo",
""
],
[
"Vallisneri",
"Michele",
""
]
] | In special relativity, the definition of coordinate systems adapted to generic accelerated observers is a long-standing problem, which has found unequivocal solutions only for the simplest motions. We show that the Marzke-Wheeler construction, an extension of the Einstein synchronization convention, produces accelerated systems of coordinates with desirable properties: (a) they reduce to Lorentz coordinates in a neighborhood of the observers' world-lines; (b) they index continuously and completely the causal envelope of the world-line (that is, the intersection of its causal past and its causal future: for well-behaved world-lines, the entire space-time). In particular, Marzke-Wheeler coordinates provide a smooth and consistent foliation of the causal envelope of any accelerated observer into space-like surfaces. We compare the Marzke-Wheeler procedure with other definitions of accelerated coordinates; we examine it in the special case of stationary motions, and we provide explicit coordinate transformations for uniformly accelerated and uniformly rotating observers. Finally, we employ the notion of Marzke-Wheeler simultaneity to clarify the relativistic paradox of the twins, by pinpointing the local origin of differential aging. |
1403.7702 | David Garrison | David Garrison | Gauge Field Turbulence as a Cause of Inflation in Chern-Simons Modified
Gravity | 7 pages, 4 figures | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we study the dynamics of the Chern-Simons Inflation Model
proposed by Alexander, Marciano and Spergel. According to this model, inflation
begins when a fermion current interacts with a turbulent gauge field in a space
larger than some critical size. This mechanism appears to work by driving
energy from the initial random spectrum into a narrow band of frequencies,
similar to the inverse energy cascade seen in MHD turbulence. In this work we
focus on the dynamics of the interaction using phase diagrams and a thorough
analysis of the evolution equations. We show that in this model inflation is
caused by an over-damped harmonic oscillator driving waves in the gauge field
at their resonance frequency.
| [
{
"created": "Sun, 30 Mar 2014 04:38:41 GMT",
"version": "v1"
}
] | 2014-04-01 | [
[
"Garrison",
"David",
""
]
] | In this paper, we study the dynamics of the Chern-Simons Inflation Model proposed by Alexander, Marciano and Spergel. According to this model, inflation begins when a fermion current interacts with a turbulent gauge field in a space larger than some critical size. This mechanism appears to work by driving energy from the initial random spectrum into a narrow band of frequencies, similar to the inverse energy cascade seen in MHD turbulence. In this work we focus on the dynamics of the interaction using phase diagrams and a thorough analysis of the evolution equations. We show that in this model inflation is caused by an over-damped harmonic oscillator driving waves in the gauge field at their resonance frequency. |
0911.2190 | Mattias Marklund | G. Brodin, M. Forsberg, M. Marklund, D. Eriksson | Interaction between gravitational waves and plasma waves in the Vlasov
description | 9 pages, uses jpp.cls | null | 10.1017/S0022377809990535 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The nonlinear interaction between electromagnetic, electrostatic and
gravitational waves in a Vlasov plasma is reconsidered. By using a orthonormal
tetrad description the three-wave coupling coefficients are computed. Comparing
with previous results, it is found that the present theory leads to algebraic
expression that are much reduced, as compared to those computed using a
coordinate frame formalism. Furthermore, here we calculate the back-reaction on
the gravitational waves, and a simple energy conservation law is deduced in the
limit of a cold plasma.
| [
{
"created": "Wed, 11 Nov 2009 17:41:09 GMT",
"version": "v1"
}
] | 2015-05-14 | [
[
"Brodin",
"G.",
""
],
[
"Forsberg",
"M.",
""
],
[
"Marklund",
"M.",
""
],
[
"Eriksson",
"D.",
""
]
] | The nonlinear interaction between electromagnetic, electrostatic and gravitational waves in a Vlasov plasma is reconsidered. By using a orthonormal tetrad description the three-wave coupling coefficients are computed. Comparing with previous results, it is found that the present theory leads to algebraic expression that are much reduced, as compared to those computed using a coordinate frame formalism. Furthermore, here we calculate the back-reaction on the gravitational waves, and a simple energy conservation law is deduced in the limit of a cold plasma. |
2207.10612 | Chandrasekhar Bhamidipati | Pavan Kumar Yerra and Chandrasekhar Bhamidipati | Topology of Born-Infeld AdS black holes in 4D novel
Einstein-Gauss-Bonnet gravity | v1: 14 pages, 5 figures; v2: 17 pages, 7 figures, minor changes,
matches published version | Phys.Lett.B 835 (2022) 137591 | 10.1016/j.physletb.2022.137591 | null | gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | The topological classification of critical points of black holes in 4D
Einstein-Gauss-Bonnet gravity coupled to Born-Infeld theory is investigated.
Considered independently, Born-infeld corrections to the Einstein action alter
the topological charge of critical points of the charged AdS black hole system,
whereas the Gauss-Bonnet corrections do not. For the combined system though,
the total topological charge of the Einstein-Gauss-Bonnet theory is unaltered
in the presence of Born-Infeld coupling.
| [
{
"created": "Thu, 21 Jul 2022 17:10:23 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Dec 2022 15:41:03 GMT",
"version": "v2"
}
] | 2022-12-16 | [
[
"Yerra",
"Pavan Kumar",
""
],
[
"Bhamidipati",
"Chandrasekhar",
""
]
] | The topological classification of critical points of black holes in 4D Einstein-Gauss-Bonnet gravity coupled to Born-Infeld theory is investigated. Considered independently, Born-infeld corrections to the Einstein action alter the topological charge of critical points of the charged AdS black hole system, whereas the Gauss-Bonnet corrections do not. For the combined system though, the total topological charge of the Einstein-Gauss-Bonnet theory is unaltered in the presence of Born-Infeld coupling. |
2407.17578 | Hector O. Silva | Hector O. Silva | Neutron stars as extreme gravity probes | 46 pages, 8 figures. Review Chapter for the book "Recent Progress on
Gravity Tests" (Eds. C. Bambi and A. C\'ardenas-Avenda\~no, Springer
Singapore) | null | 10.1007/978-981-97-2871-8_4 | null | gr-qc astro-ph.HE hep-th | http://creativecommons.org/licenses/by/4.0/ | Neutron stars are powerful probes into the extremes of physics. In this
chapter, we will discuss how observations of neutron stars, either in isolation
or in binaries, can be leveraged to test general relativity and constrain
competing theories of gravity.
| [
{
"created": "Wed, 24 Jul 2024 18:31:45 GMT",
"version": "v1"
}
] | 2024-07-26 | [
[
"Silva",
"Hector O.",
""
]
] | Neutron stars are powerful probes into the extremes of physics. In this chapter, we will discuss how observations of neutron stars, either in isolation or in binaries, can be leveraged to test general relativity and constrain competing theories of gravity. |
1410.6211 | Shivaraj Kandhasamy | The LIGO Scientific Collaboration, the Virgo Collaboration: J. Aasi,
J. Abadie, B. P. Abbott, R. Abbott, T. Abbott, M. R. Abernathy, T. Accadia,
F. Acernese, C. Adams, T. Adams, P. Addesso, R. X. Adhikari, C. Affeldt, M.
Agathos, N. Aggarwal, O. D. Aguiar, P. Ajith, B. Allen, A. Allocca, E. Amado.
Ceron, D. Amariutei, R. A. Anderson, S. B. Anderson, W. G. Anderson, K. Arai,
M. C. Araya, C. Arceneaux, J. Areeda, S. Ast, S. M. Aston, P. Astone, P.
Aufmuth, C. Aulbert, L. Austin, B. E. Aylott, S. Babak, P. T. Baker, G.
Ballardin, S. W. Ballmer, J. C. Barayoga, D. Barker, S. H. Barnum, F. Barone,
B. Barr, L. Barsotti, M. Barsuglia, M. A. Barton, I. Bartos, R. Bassiri, A.
Basti, J. Batch, J. Bauchrowitz, Th. S. Bauer, M. Bebronne, B. Behnke, M.
Bejger, M. G. Beker, A. S. Bell, C. Bell, I. Belopolski, G. Bergmann, J. M.
Berliner, D. Bersanetti, A. Bertolini, D. Bessis, J. Betzwieser, P. T.
Beyersdorf, T. Bhadbhade, I. A. Bilenko, G. Billingsley, J. Birch, S.
Biscans, M. Bitossi, M. A. Bizouard, E. Black, J. K. Blackburn, L. Blackburn,
D. Blair, M. Blom, O. Bock, T. P. Bodiya, M. Boer, C. Bogan, C. Bond, F.
Bondu, L. Bonelli, R. Bonnand, R. Bork, M. Born, V. Boschi, S. Bose, L. Bosi,
J. Bowers, C. Bradaschia, P. R. Brady, V. B. Braginsky, M. Branchesi, C. A.
Brannen, J. E. Brau, J. Breyer, T. Briant, D. O. Bridges, A. Brillet, M.
Brinkmann, V. Brisson, M. Britzger, A. F. Brooks, D. A. Brown, D. D. Brown,
F. Br\"uckner, T. Bulik, H. J. Bulten, A. Buonanno, D. Buskulic, C. Buy, R.
L. Byer, L. Cadonati, G. Cagnoli, J. Calder\'o. Bustillo, E. Calloni, J. B.
Camp, P. Campsie, K. C. Cannon, B. Canuel, J. Cao, C. D. Capano, F.
Carbognani, L. Carbone, S. Caride, A. Castiglia, S. Caudill, M. Cavagli\`a,
F. Cavalier, R. Cavalieri, G. Cella, C. Cepeda, E. Cesarini, R. Chakraborty,
T. Chalermsongsak, S. Chao, P. Charlton, E. Chassande-Mottin, X. Chen, Y.
Chen, A. Chincarini, A. Chiummo, H. S. Cho, J. Chow, N. Christensen, Q. Chu,
S. S. Y. Chua, S. Chung, G. Ciani, F. Clara, D. E. Clark, J. A. Clark, F.
Cleva, E. Coccia, P.-F. Cohadon, A. Colla, M. Colombini, M. Constanci. Jr.,
A. Conte, D. Cook, T. R. Corbitt, M. Cordier, N. Cornish, A. Corsi, C. A.
Costa, M. W. Coughlin, J.-P. Coulon, S. Countryman, P. Couvares, D. M.
Coward, M. Cowart, D. C. Coyne, K. Craig, J. D. E. Creighton, T. D.
Creighton, S. G. Crowder, A. Cumming, L. Cunningham, E. Cuoco, K. Dahl, T.
Da. Canton, M. Damjanic, S. L. Danilishin, S. D'Antonio, K. Danzmann, V.
Dattilo, B. Daudert, H. Daveloza, M. Davier, G. S. Davies, E. J. Daw, R. Day,
T. Dayanga, G. Debreczeni, J. Degallaix, E. Deleeuw, S. Del\'eglise, W. De.
Pozzo, T. Denker, T. Dent, H. Dereli, V. Dergachev, R. T. DeRosa, R. D. Rosa,
R. DeSalvo, S. Dhurandhar, M. D\'iaz, A. Dietz, L. D. Fiore, A. D. Lieto, I.
D. Palma, A. D. Virgilio, K. Dmitry, F. Donovan, K. L. Dooley, S. Doravari,
M. Drago, R. W. P. Drever, J. C. Driggers, Z. Du, J. -C. Dumas, S. Dwyer, T.
Eberle, M. Edwards, A. Effler, P. Ehrens, J. Eichholz, S. S. Eikenberry, G.
Endr\H{o}czi, R. Essick, T. Etzel, K. Evans, M. Evans, T. Evans, M.
Factourovich, V. Fafone, S. Fairhurst, Q. Fang, B. Farr, W. Farr, M. Favata,
D. Fazi, H. Fehrmann, D. Feldbaum, I. Ferrante, F. Ferrini, F. Fidecaro, L.
S. Finn, I. Fiori, R. Fisher, R. Flaminio, E. Foley, S. Foley, E. Forsi, N.
Fotopoulos, J.-D. Fournier, S. Franco, S. Frasca, F. Frasconi, M. Frede, M.
Frei, Z. Frei, A. Freise, R. Frey, T. T. Fricke, P. Fritschel, V. V. Frolov,
M.-K. Fujimoto, P. Fulda, M. Fyffe, J. Gair, L. Gammaitoni, J. Garcia, F.
Garufi, N. Gehrels, G. Gemme, E. Genin, A. Gennai, L. Gergely, S. Ghosh, J.
A. Giaime, S. Giampanis, K. D. Giardina, A. Giazotto, S. Gil-Casanova, C.
Gill, J. Gleason, E. Goetz, R. Goetz, L. Gondan, G. Gonz\'alez, N. Gordon, M.
L. Gorodetsky, S. Gossan, S. Go{\ss}ler, R. Gouaty, C. Graef, P. B. Graff, M.
Granata, A. Grant, S. Gras, C. Gray, R. J. S. Greenhalgh, A. M. Gretarsson,
C. Griffo, H. Grote, K. Grover, S. Grunewald, G. M. Guidi, C. Guido, K. E.
Gushwa, E. K. Gustafson, R. Gustafson, B. Hall, E. Hall, D. Hammer, G.
Hammond, M. Hanke, J. Hanks, C. Hanna, J. Hanson, J. Harms, G. M. Harry, I.
W. Harry, E. D. Harstad, M. T. Hartman, K. Haughian, K. Hayama, J. Heefner,
A. Heidmann, M. Heintze, H. Heitmann, P. Hello, G. Hemming, M. Hendry, I. S.
Heng, A. W. Heptonstall, M. Heurs, S. Hild, D. Hoak, K. A. Hodge, K. Holt, T.
Hong, S. Hooper, T. Horrom, D. J. Hosken, J. Hough, E. J. Howell, Y. Hu, Z.
Hua, V. Huang, E. A. Huerta, B. Hughey, S. Husa, S. H. Huttner, M. Huynh, T.
Huynh-Dinh, J. Iafrate, D. R. Ingram, R. Inta, T. Isogai, A. Ivanov, B. R.
Iyer, K. Izumi, M. Jacobson, E. James, H. Jang, Y. J. Jang, P. Jaranowski, F.
Jim\'enez-Forteza, W. W. Johnson, D. I. Jones, D. Jones, R. Jones, R.J.G.
Jonker, L. Ju, Hari. K, P. Kalmus, V. Kalogera, S. Kandhasamy, G. Kang, J. B.
Kanner, M. Kasprzack, R. Kasturi, E. Katsavounidis, W. Katzman, H. Kaufer, K.
Kaufman, K. Kawabe, S. Kawamura, F. Kawazoe, F. K\'ef\'elian, D. Keitel, D.
B. Kelley, W. Kells, D. G. Keppel, A. Khalaidovski, F. Y. Khalili, E. A.
Khazanov, B. K. Kim, C. Kim, K. Kim, N. Kim, W. Kim, Y.-M. Kim, E. King, P.
J. King, D. L. Kinzel, J. S. Kissel, S. Klimenko, J. Kline, S. Koehlenbeck,
K. Kokeyama, V. Kondrashov, S. Koranda, W. Z. Korth, I. Kowalska, D. Kozak,
A. Kremin, V. Kringel, B. Krishnan, A. Kr\'olak, C. Kucharczyk, S. Kudla, G.
Kuehn, A. Kumar, D. Nand. Kumar, P. Kumar, R. Kumar, R. Kurdyumov, P. Kwee,
M. Landry, B. Lantz, S. Larson, P. D. Lasky, C. Lawrie, A. Lazzarini, P.
Leaci, E. O. Lebigot, C.-H. Lee, H. K. Lee, H. M. Lee, J. J. Lee, J. Lee, M.
Leonardi, J. R. Leong, A. L. Roux, N. Leroy, N. Letendre, B. Levine, J. B.
Lewis, V. Lhuillier, T. G. F. Li, A. C. Lin, T. B. Littenberg, V. Litvine, F.
Liu, H. Liu, Y. Liu, Z. Liu, D. Lloyd, N. A. Lockerbie, V. Lockett, D.
Lodhia, K. Loew, J. Logue, A. L. Lombardi, M. Lorenzini, V. Loriette, M.
Lormand, G. Losurdo, J. Lough, J. Luan, M. J. Lubinski, H. L\"uck, A. P.
Lundgren, J. Macarthur, E. Macdonald, B. Machenschalk, M. MacInnis, D. M.
Macleod, F. Magana-Sandoval, M. Mageswaran, K. Mailand, E. Majorana, I.
Maksimovic, V. Malvezzi, N. Man, G. M. Manca, I. Mandel, V. Mandic, V.
Mangano, M. Mantovani, F. Marchesoni, F. Marion, S. M\'arka, Z. M\'arka, A.
Markosyan, E. Maros, J. Marque, F. Martelli, L. Martellini, I. W. Martin, R.
M. Martin, G. Martini, D. Martynov, J. N. Marx, K. Mason, A. Masserot, T. J.
Massinger, F. Matichard, L. Matone, R. A. Matzner, N. Mavalvala, G. May, N.
Mazumder, G. Mazzolo, R. McCarthy, D. E. McClelland, S. C. McGuire, G.
McIntyre, J. McIver, D. Meacher, G. D. Meadors, M. Mehmet, J. Meidam, T.
Meier, A. Melatos, G. Mendell, R. A. Mercer, S. Meshkov, C. Messenger, M. S.
Meyer, H. Miao, C. Michel, E. Mikhailov, L. Milano, J. Miller, Y. Minenkov,
C. M. F. Mingarelli, S. Mitra, V. P. Mitrofanov, G. Mitselmakher, R.
Mittleman, B. Moe, M. Mohan, S. R. P. Mohapatra, F. Mokler, D. Moraru, G.
Moreno, N. Morgado, T. Mori, S. R. Morriss, K. Mossavi, B. Mours, C. M.
Mow-Lowry, C. L. Mueller, G. Mueller, S. Mukherjee, A. Mullavey, J. Munch, D.
Murphy, P. G. Murray, A. Mytidis, M. F. Nagy, I. Nardecchia, T. Nash, L.
Naticchioni, R. Nayak, V. Necula, I. Neri, M. Neri, G. Newton, T. Nguyen, E.
Nishida, A. Nishizawa, A. Nitz, F. Nocera, D. Nolting, M. E. Normandin, L. K.
Nuttall, E. Ochsner, J. O'Dell, E. Oelker, G. H. Ogin, J. J. Oh, S. H. Oh, F.
Ohme, P. Oppermann, B. O'Reilly, W. Orteg. Larcher, R. O'Shaughnessy, C.
Osthelder, D. J. Ottaway, R. S. Ottens, J. Ou, H. Overmier, B. J. Owen, C.
Padilla, A. Pai, C. Palomba, Y. Pan, C. Pankow, F. Paoletti, R. Paoletti, H.
Paris, A. Pasqualetti, R. Passaquieti, D. Passuello, M. Pedraza, P. Peiris,
S. Penn, A. Perreca, M. Phelps, M. Pichot, M. Pickenpack, F. Piergiovanni, V.
Pierro, L. Pinard, B. Pindor, I. M. Pinto, M. Pitkin, J. Poeld, R. Poggiani,
V. Poole, F. Postiglione, C. Poux, V. Predoi, T. Prestegard, L. R. Price, M.
Prijatelj, S. Privitera, G. A. Prodi, L. Prokhorov, O. Puncken, M. Punturo,
P. Puppo, V. Quetschke, E. Quintero, R. Quitzow-James, F. J. Raab, D. S.
Rabeling, I. R\'acz, H. Radkins, P. Raffai, S. Raja, G. Rajalakshmi, M.
Rakhmanov, C. Ramet, P. Rapagnani, V. Raymond, V. Re, C. M. Reed, T. Reed, T.
Regimbau, S. Reid, D. H. Reitze, F. Ricci, R. Riesen, K. Riles, N. A.
Robertson, F. Robinet, A. Rocchi, S. Roddy, C. Rodriguez, M. Rodruck, C.
Roever, L. Rolland, J. G. Rollins, J. D. Romano, R. Romano, G. Romanov, J. H.
Romie, D. Rosi\'nska, S. Rowan, A. R\"udiger, P. Ruggi, K. Ryan, F. Salemi,
L. Sammut, V. Sandberg, J. Sanders, V. Sannibale, I. Santiago-Prieto, E.
Saracco, B. Sassolas, B. S. Sathyaprakash, P. R. Saulson, R. Savage, R.
Schilling, R. Schnabel, R. M. S. Schofield, E. Schreiber, D. Schuette, B.
Schulz, B. F. Schutz, P. Schwinberg, J. Scott, S. M. Scott, F. Seifert, D.
Sellers, A. S. Sengupta, D. Sentenac, V. Sequino, A. Sergeev, D. Shaddock, S.
Shah, M. S. Shahriar, M. Shaltev, B. Shapiro, P. Shawhan, D. H. Shoemaker, T.
L. Sidery, K. Siellez, X. Siemens, D. Sigg, D. Simakov, A. Singer, L. Singer,
A. M. Sintes, G. R. Skelton, B. J. J. Slagmolen, J. Slutsky, J. R. Smith, M.
R. Smith, R. J. E. Smith, N. D. Smith-Lefebvre, K. Soden, E. J. Son, B.
Sorazu, T. Souradeep, L. Sperandio, A. Staley, E. Steinert, J. Steinlechner,
S. Steinlechner, S. Steplewski, D. Stevens, A. Stochino, R. Stone, K. A.
Strain, N. Straniero, S. Strigin, A. S. Stroeer, R. Sturani, A. L. Stuver, T.
Z. Summerscales, S. Susmithan, P. J. Sutton, B. Swinkels, G. Szeifert, M.
Tacca, D. Talukder, L. Tang, D. B. Tanner, S. P. Tarabrin, R. Taylor, A. P.
M. te. Braack, M. P. Thirugnanasambandam, M. Thomas, P. Thomas, K. A. Thorne,
K. S. Thorne, E. Thrane, V. Tiwari, K. V. Tokmakov, C. Tomlinson, A.
Toncelli, M. Tonelli, O. Torre, C. V. Torres, C. I. Torrie, F. Travasso, G.
Traylor, M. Tse, D. Ugolini, C. S. Unnikrishnan, H. Vahlbruch, G. Vajente, M.
Vallisneri, J. F. J. va. de. Brand, C. Va. De. Broeck, S. va. de. Putten, M.
V. va. de. Sluys, J. va. Heijningen, A. A. va. Veggel, S. Vass, M. Vas\'uth,
R. Vaulin, A. Vecchio, G. Vedovato, P. J. Veitch, J. Veitch, K. Venkateswara,
D. Verkindt, S. Verma, F. Vetrano, A. Vicer\'e, R. Vincent-Finley, J.-Y.
Vinet, S. Vitale, S. Vitale, B. Vlcek, T. Vo, H. Vocca, C. Vorvick, W. D.
Vousden, D. Vrinceanu, S. P. Vyachanin, A. Wade, L. Wade, M. Wade, S. J.
Waldman, M. Walker, L. Wallace, Y. Wan, J. Wang, M. Wang, X. Wang, A. Wanner,
R. L. Ward, M. Was, B. Weaver, L.-W. Wei, M. Weinert, A. J. Weinstein, R.
Weiss, T. Welborn, L. Wen, P. Wessels, M. West, T. Westphal, K. Wette, J. T.
Whelan, D. J. White, B. F. Whiting, S. Wibowo, K. Wiesner, C. Wilkinson, L.
Williams, R. Williams, T. Williams, J. L. Willis, B. Willke, M. Wimmer, L.
Winkelmann, W. Winkler, C. C. Wipf, H. Wittel, G. Woan, J. Worden, J. Yablon,
I. Yakushin, H. Yamamoto, C. C. Yancey, H. Yang, D. Yeaton-Massey, S.
Yoshida, H. Yum, M. Yvert, A. Zadro\.zny, M. Zanolin, J.-P. Zendri, F. Zhang,
L. Zhang, C. Zhao, H. Zhu, X. J. Zhu, N. Zotov, M. E. Zucker, and J. Zweizig | Searching for stochastic gravitational waves using data from the two
co-located LIGO Hanford detectors | 21 pages, 10 figures, 5 tables | Phys. Rev. D 91, 022003 (2015) | 10.1103/PhysRevD.91.022003 | null | gr-qc astro-ph.IM | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Searches for a stochastic gravitational-wave background (SGWB) using
terrestrial detectors typically involve cross-correlating data from pairs of
detectors. The sensitivity of such cross-correlation analyses depends, among
other things, on the separation between the two detectors: the smaller the
separation, the better the sensitivity. Hence, a co-located detector pair is
more sensitive to a gravitational-wave background than a non-co-located
detector pair. However, co-located detectors are also expected to suffer from
correlated noise from instrumental and environmental effects that could
contaminate the measurement of the background. Hence, methods to identify and
mitigate the effects of correlated noise are necessary to achieve the potential
increase in sensitivity of co-located detectors. Here we report on the first
SGWB analysis using the two LIGO Hanford detectors and address the
complications arising from correlated environmental noise. We apply correlated
noise identification and mitigation techniques to data taken by the two LIGO
Hanford detectors, H1 and H2, during LIGO's fifth science run. At low
frequencies, 40 - 460 Hz, we are unable to sufficiently mitigate the correlated
noise to a level where we may confidently measure or bound the stochastic
gravitational-wave signal. However, at high frequencies, 460-1000 Hz, these
techniques are sufficient to set a $95%$ confidence level (C.L.) upper limit on
the gravitational-wave energy density of \Omega(f)<7.7 x 10^{-4} (f/ 900 Hz)^3,
which improves on the previous upper limit by a factor of $\sim 180$. In doing
so, we demonstrate techniques that will be useful for future searches using
advanced detectors, where correlated noise (e.g., from global magnetic fields)
may affect even widely separated detectors.
| [
{
"created": "Wed, 22 Oct 2014 23:34:59 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Nov 2014 06:49:33 GMT",
"version": "v2"
},
{
"created": "Wed, 3 Dec 2014 00:01:40 GMT",
"version": "v3"
}
] | 2015-01-14 | [
[
"The LIGO Scientific Collaboration",
"",
""
],
[
"the Virgo Collaboration",
"",
""
],
[
"Aasi",
"J.",
""
],
[
"Abadie",
"J.",
""
],
[
"Abbott",
"B. P.",
""
],
[
"Abbott",
"R.",
""
],
[
"Abbott",
"T.",
""
],
[
"Abernathy",
"M. R.",
""
],
[
"Accadia",
"T.",
""
],
[
"Acernese",
"F.",
""
],
[
"Adams",
"C.",
""
],
[
"Adams",
"T.",
""
],
[
"Addesso",
"P.",
""
],
[
"Adhikari",
"R. X.",
""
],
[
"Affeldt",
"C.",
""
],
[
"Agathos",
"M.",
""
],
[
"Aggarwal",
"N.",
""
],
[
"Aguiar",
"O. D.",
""
],
[
"Ajith",
"P.",
""
],
[
"Allen",
"B.",
""
],
[
"Allocca",
"A.",
""
],
[
"Ceron",
"E. Amado.",
""
],
[
"Amariutei",
"D.",
""
],
[
"Anderson",
"R. A.",
""
],
[
"Anderson",
"S. B.",
""
],
[
"Anderson",
"W. G.",
""
],
[
"Arai",
"K.",
""
],
[
"Araya",
"M. C.",
""
],
[
"Arceneaux",
"C.",
""
],
[
"Areeda",
"J.",
""
],
[
"Ast",
"S.",
""
],
[
"Aston",
"S. M.",
""
],
[
"Astone",
"P.",
""
],
[
"Aufmuth",
"P.",
""
],
[
"Aulbert",
"C.",
""
],
[
"Austin",
"L.",
""
],
[
"Aylott",
"B. E.",
""
],
[
"Babak",
"S.",
""
],
[
"Baker",
"P. T.",
""
],
[
"Ballardin",
"G.",
""
],
[
"Ballmer",
"S. W.",
""
],
[
"Barayoga",
"J. C.",
""
],
[
"Barker",
"D.",
""
],
[
"Barnum",
"S. H.",
""
],
[
"Barone",
"F.",
""
],
[
"Barr",
"B.",
""
],
[
"Barsotti",
"L.",
""
],
[
"Barsuglia",
"M.",
""
],
[
"Barton",
"M. A.",
""
],
[
"Bartos",
"I.",
""
],
[
"Bassiri",
"R.",
""
],
[
"Basti",
"A.",
""
],
[
"Batch",
"J.",
""
],
[
"Bauchrowitz",
"J.",
""
],
[
"Bauer",
"Th. S.",
""
],
[
"Bebronne",
"M.",
""
],
[
"Behnke",
"B.",
""
],
[
"Bejger",
"M.",
""
],
[
"Beker",
"M. G.",
""
],
[
"Bell",
"A. S.",
""
],
[
"Bell",
"C.",
""
],
[
"Belopolski",
"I.",
""
],
[
"Bergmann",
"G.",
""
],
[
"Berliner",
"J. M.",
""
],
[
"Bersanetti",
"D.",
""
],
[
"Bertolini",
"A.",
""
],
[
"Bessis",
"D.",
""
],
[
"Betzwieser",
"J.",
""
],
[
"Beyersdorf",
"P. T.",
""
],
[
"Bhadbhade",
"T.",
""
],
[
"Bilenko",
"I. A.",
""
],
[
"Billingsley",
"G.",
""
],
[
"Birch",
"J.",
""
],
[
"Biscans",
"S.",
""
],
[
"Bitossi",
"M.",
""
],
[
"Bizouard",
"M. A.",
""
],
[
"Black",
"E.",
""
],
[
"Blackburn",
"J. K.",
""
],
[
"Blackburn",
"L.",
""
],
[
"Blair",
"D.",
""
],
[
"Blom",
"M.",
""
],
[
"Bock",
"O.",
""
],
[
"Bodiya",
"T. P.",
""
],
[
"Boer",
"M.",
""
],
[
"Bogan",
"C.",
""
],
[
"Bond",
"C.",
""
],
[
"Bondu",
"F.",
""
],
[
"Bonelli",
"L.",
""
],
[
"Bonnand",
"R.",
""
],
[
"Bork",
"R.",
""
],
[
"Born",
"M.",
""
],
[
"Boschi",
"V.",
""
],
[
"Bose",
"S.",
""
],
[
"Bosi",
"L.",
""
],
[
"Bowers",
"J.",
""
],
[
"Bradaschia",
"C.",
""
],
[
"Brady",
"P. R.",
""
],
[
"Braginsky",
"V. B.",
""
],
[
"Branchesi",
"M.",
""
],
[
"Brannen",
"C. A.",
""
],
[
"Brau",
"J. E.",
""
],
[
"Breyer",
"J.",
""
],
[
"Briant",
"T.",
""
],
[
"Bridges",
"D. O.",
""
],
[
"Brillet",
"A.",
""
],
[
"Brinkmann",
"M.",
""
],
[
"Brisson",
"V.",
""
],
[
"Britzger",
"M.",
""
],
[
"Brooks",
"A. F.",
""
],
[
"Brown",
"D. A.",
""
],
[
"Brown",
"D. D.",
""
],
[
"Brückner",
"F.",
""
],
[
"Bulik",
"T.",
""
],
[
"Bulten",
"H. J.",
""
],
[
"Buonanno",
"A.",
""
],
[
"Buskulic",
"D.",
""
],
[
"Buy",
"C.",
""
],
[
"Byer",
"R. L.",
""
],
[
"Cadonati",
"L.",
""
],
[
"Cagnoli",
"G.",
""
],
[
"Bustillo",
"J. Calderó.",
""
],
[
"Calloni",
"E.",
""
],
[
"Camp",
"J. B.",
""
],
[
"Campsie",
"P.",
""
],
[
"Cannon",
"K. C.",
""
],
[
"Canuel",
"B.",
""
],
[
"Cao",
"J.",
""
],
[
"Capano",
"C. D.",
""
],
[
"Carbognani",
"F.",
""
],
[
"Carbone",
"L.",
""
],
[
"Caride",
"S.",
""
],
[
"Castiglia",
"A.",
""
],
[
"Caudill",
"S.",
""
],
[
"Cavaglià",
"M.",
""
],
[
"Cavalier",
"F.",
""
],
[
"Cavalieri",
"R.",
""
],
[
"Cella",
"G.",
""
],
[
"Cepeda",
"C.",
""
],
[
"Cesarini",
"E.",
""
],
[
"Chakraborty",
"R.",
""
],
[
"Chalermsongsak",
"T.",
""
],
[
"Chao",
"S.",
""
],
[
"Charlton",
"P.",
""
],
[
"Chassande-Mottin",
"E.",
""
],
[
"Chen",
"X.",
""
],
[
"Chen",
"Y.",
""
],
[
"Chincarini",
"A.",
""
],
[
"Chiummo",
"A.",
""
],
[
"Cho",
"H. S.",
""
],
[
"Chow",
"J.",
""
],
[
"Christensen",
"N.",
""
],
[
"Chu",
"Q.",
""
],
[
"Chua",
"S. S. Y.",
""
],
[
"Chung",
"S.",
""
],
[
"Ciani",
"G.",
""
],
[
"Clara",
"F.",
""
],
[
"Clark",
"D. E.",
""
],
[
"Clark",
"J. A.",
""
],
[
"Cleva",
"F.",
""
],
[
"Coccia",
"E.",
""
],
[
"Cohadon",
"P. -F.",
""
],
[
"Colla",
"A.",
""
],
[
"Colombini",
"M.",
""
],
[
"Constanci.",
"M.",
"Jr."
],
[
"Conte",
"A.",
""
],
[
"Cook",
"D.",
""
],
[
"Corbitt",
"T. R.",
""
],
[
"Cordier",
"M.",
""
],
[
"Cornish",
"N.",
""
],
[
"Corsi",
"A.",
""
],
[
"Costa",
"C. A.",
""
],
[
"Coughlin",
"M. W.",
""
],
[
"Coulon",
"J. -P.",
""
],
[
"Countryman",
"S.",
""
],
[
"Couvares",
"P.",
""
],
[
"Coward",
"D. M.",
""
],
[
"Cowart",
"M.",
""
],
[
"Coyne",
"D. C.",
""
],
[
"Craig",
"K.",
""
],
[
"Creighton",
"J. D. E.",
""
],
[
"Creighton",
"T. D.",
""
],
[
"Crowder",
"S. G.",
""
],
[
"Cumming",
"A.",
""
],
[
"Cunningham",
"L.",
""
],
[
"Cuoco",
"E.",
""
],
[
"Dahl",
"K.",
""
],
[
"Canton",
"T. Da.",
""
],
[
"Damjanic",
"M.",
""
],
[
"Danilishin",
"S. L.",
""
],
[
"D'Antonio",
"S.",
""
],
[
"Danzmann",
"K.",
""
],
[
"Dattilo",
"V.",
""
],
[
"Daudert",
"B.",
""
],
[
"Daveloza",
"H.",
""
],
[
"Davier",
"M.",
""
],
[
"Davies",
"G. S.",
""
],
[
"Daw",
"E. J.",
""
],
[
"Day",
"R.",
""
],
[
"Dayanga",
"T.",
""
],
[
"Debreczeni",
"G.",
""
],
[
"Degallaix",
"J.",
""
],
[
"Deleeuw",
"E.",
""
],
[
"Deléglise",
"S.",
""
],
[
"Pozzo",
"W. De.",
""
],
[
"Denker",
"T.",
""
],
[
"Dent",
"T.",
""
],
[
"Dereli",
"H.",
""
],
[
"Dergachev",
"V.",
""
],
[
"DeRosa",
"R. T.",
""
],
[
"Rosa",
"R. D.",
""
],
[
"DeSalvo",
"R.",
""
],
[
"Dhurandhar",
"S.",
""
],
[
"Díaz",
"M.",
""
],
[
"Dietz",
"A.",
""
],
[
"Fiore",
"L. D.",
""
],
[
"Lieto",
"A. D.",
""
],
[
"Palma",
"I. D.",
""
],
[
"Virgilio",
"A. D.",
""
],
[
"Dmitry",
"K.",
""
],
[
"Donovan",
"F.",
""
],
[
"Dooley",
"K. L.",
""
],
[
"Doravari",
"S.",
""
],
[
"Drago",
"M.",
""
],
[
"Drever",
"R. W. P.",
""
],
[
"Driggers",
"J. C.",
""
],
[
"Du",
"Z.",
""
],
[
"Dumas",
"J. -C.",
""
],
[
"Dwyer",
"S.",
""
],
[
"Eberle",
"T.",
""
],
[
"Edwards",
"M.",
""
],
[
"Effler",
"A.",
""
],
[
"Ehrens",
"P.",
""
],
[
"Eichholz",
"J.",
""
],
[
"Eikenberry",
"S. S.",
""
],
[
"Endrőczi",
"G.",
""
],
[
"Essick",
"R.",
""
],
[
"Etzel",
"T.",
""
],
[
"Evans",
"K.",
""
],
[
"Evans",
"M.",
""
],
[
"Evans",
"T.",
""
],
[
"Factourovich",
"M.",
""
],
[
"Fafone",
"V.",
""
],
[
"Fairhurst",
"S.",
""
],
[
"Fang",
"Q.",
""
],
[
"Farr",
"B.",
""
],
[
"Farr",
"W.",
""
],
[
"Favata",
"M.",
""
],
[
"Fazi",
"D.",
""
],
[
"Fehrmann",
"H.",
""
],
[
"Feldbaum",
"D.",
""
],
[
"Ferrante",
"I.",
""
],
[
"Ferrini",
"F.",
""
],
[
"Fidecaro",
"F.",
""
],
[
"Finn",
"L. S.",
""
],
[
"Fiori",
"I.",
""
],
[
"Fisher",
"R.",
""
],
[
"Flaminio",
"R.",
""
],
[
"Foley",
"E.",
""
],
[
"Foley",
"S.",
""
],
[
"Forsi",
"E.",
""
],
[
"Fotopoulos",
"N.",
""
],
[
"Fournier",
"J. -D.",
""
],
[
"Franco",
"S.",
""
],
[
"Frasca",
"S.",
""
],
[
"Frasconi",
"F.",
""
],
[
"Frede",
"M.",
""
],
[
"Frei",
"M.",
""
],
[
"Frei",
"Z.",
""
],
[
"Freise",
"A.",
""
],
[
"Frey",
"R.",
""
],
[
"Fricke",
"T. T.",
""
],
[
"Fritschel",
"P.",
""
],
[
"Frolov",
"V. V.",
""
],
[
"Fujimoto",
"M. -K.",
""
],
[
"Fulda",
"P.",
""
],
[
"Fyffe",
"M.",
""
],
[
"Gair",
"J.",
""
],
[
"Gammaitoni",
"L.",
""
],
[
"Garcia",
"J.",
""
],
[
"Garufi",
"F.",
""
],
[
"Gehrels",
"N.",
""
],
[
"Gemme",
"G.",
""
],
[
"Genin",
"E.",
""
],
[
"Gennai",
"A.",
""
],
[
"Gergely",
"L.",
""
],
[
"Ghosh",
"S.",
""
],
[
"Giaime",
"J. A.",
""
],
[
"Giampanis",
"S.",
""
],
[
"Giardina",
"K. D.",
""
],
[
"Giazotto",
"A.",
""
],
[
"Gil-Casanova",
"S.",
""
],
[
"Gill",
"C.",
""
],
[
"Gleason",
"J.",
""
],
[
"Goetz",
"E.",
""
],
[
"Goetz",
"R.",
""
],
[
"Gondan",
"L.",
""
],
[
"González",
"G.",
""
],
[
"Gordon",
"N.",
""
],
[
"Gorodetsky",
"M. L.",
""
],
[
"Gossan",
"S.",
""
],
[
"Goßler",
"S.",
""
],
[
"Gouaty",
"R.",
""
],
[
"Graef",
"C.",
""
],
[
"Graff",
"P. B.",
""
],
[
"Granata",
"M.",
""
],
[
"Grant",
"A.",
""
],
[
"Gras",
"S.",
""
],
[
"Gray",
"C.",
""
],
[
"Greenhalgh",
"R. J. S.",
""
],
[
"Gretarsson",
"A. M.",
""
],
[
"Griffo",
"C.",
""
],
[
"Grote",
"H.",
""
],
[
"Grover",
"K.",
""
],
[
"Grunewald",
"S.",
""
],
[
"Guidi",
"G. M.",
""
],
[
"Guido",
"C.",
""
],
[
"Gushwa",
"K. E.",
""
],
[
"Gustafson",
"E. K.",
""
],
[
"Gustafson",
"R.",
""
],
[
"Hall",
"B.",
""
],
[
"Hall",
"E.",
""
],
[
"Hammer",
"D.",
""
],
[
"Hammond",
"G.",
""
],
[
"Hanke",
"M.",
""
],
[
"Hanks",
"J.",
""
],
[
"Hanna",
"C.",
""
],
[
"Hanson",
"J.",
""
],
[
"Harms",
"J.",
""
],
[
"Harry",
"G. M.",
""
],
[
"Harry",
"I. W.",
""
],
[
"Harstad",
"E. D.",
""
],
[
"Hartman",
"M. T.",
""
],
[
"Haughian",
"K.",
""
],
[
"Hayama",
"K.",
""
],
[
"Heefner",
"J.",
""
],
[
"Heidmann",
"A.",
""
],
[
"Heintze",
"M.",
""
],
[
"Heitmann",
"H.",
""
],
[
"Hello",
"P.",
""
],
[
"Hemming",
"G.",
""
],
[
"Hendry",
"M.",
""
],
[
"Heng",
"I. S.",
""
],
[
"Heptonstall",
"A. W.",
""
],
[
"Heurs",
"M.",
""
],
[
"Hild",
"S.",
""
],
[
"Hoak",
"D.",
""
],
[
"Hodge",
"K. A.",
""
],
[
"Holt",
"K.",
""
],
[
"Hong",
"T.",
""
],
[
"Hooper",
"S.",
""
],
[
"Horrom",
"T.",
""
],
[
"Hosken",
"D. J.",
""
],
[
"Hough",
"J.",
""
],
[
"Howell",
"E. J.",
""
],
[
"Hu",
"Y.",
""
],
[
"Hua",
"Z.",
""
],
[
"Huang",
"V.",
""
],
[
"Huerta",
"E. A.",
""
],
[
"Hughey",
"B.",
""
],
[
"Husa",
"S.",
""
],
[
"Huttner",
"S. H.",
""
],
[
"Huynh",
"M.",
""
],
[
"Huynh-Dinh",
"T.",
""
],
[
"Iafrate",
"J.",
""
],
[
"Ingram",
"D. R.",
""
],
[
"Inta",
"R.",
""
],
[
"Isogai",
"T.",
""
],
[
"Ivanov",
"A.",
""
],
[
"Iyer",
"B. R.",
""
],
[
"Izumi",
"K.",
""
],
[
"Jacobson",
"M.",
""
],
[
"James",
"E.",
""
],
[
"Jang",
"H.",
""
],
[
"Jang",
"Y. J.",
""
],
[
"Jaranowski",
"P.",
""
],
[
"Jiménez-Forteza",
"F.",
""
],
[
"Johnson",
"W. W.",
""
],
[
"Jones",
"D. I.",
""
],
[
"Jones",
"D.",
""
],
[
"Jones",
"R.",
""
],
[
"Jonker",
"R. J. G.",
""
],
[
"Ju",
"L.",
""
],
[
"K",
"Hari.",
""
],
[
"Kalmus",
"P.",
""
],
[
"Kalogera",
"V.",
""
],
[
"Kandhasamy",
"S.",
""
],
[
"Kang",
"G.",
""
],
[
"Kanner",
"J. B.",
""
],
[
"Kasprzack",
"M.",
""
],
[
"Kasturi",
"R.",
""
],
[
"Katsavounidis",
"E.",
""
],
[
"Katzman",
"W.",
""
],
[
"Kaufer",
"H.",
""
],
[
"Kaufman",
"K.",
""
],
[
"Kawabe",
"K.",
""
],
[
"Kawamura",
"S.",
""
],
[
"Kawazoe",
"F.",
""
],
[
"Kéfélian",
"F.",
""
],
[
"Keitel",
"D.",
""
],
[
"Kelley",
"D. B.",
""
],
[
"Kells",
"W.",
""
],
[
"Keppel",
"D. G.",
""
],
[
"Khalaidovski",
"A.",
""
],
[
"Khalili",
"F. Y.",
""
],
[
"Khazanov",
"E. A.",
""
],
[
"Kim",
"B. K.",
""
],
[
"Kim",
"C.",
""
],
[
"Kim",
"K.",
""
],
[
"Kim",
"N.",
""
],
[
"Kim",
"W.",
""
],
[
"Kim",
"Y. -M.",
""
],
[
"King",
"E.",
""
],
[
"King",
"P. J.",
""
],
[
"Kinzel",
"D. L.",
""
],
[
"Kissel",
"J. S.",
""
],
[
"Klimenko",
"S.",
""
],
[
"Kline",
"J.",
""
],
[
"Koehlenbeck",
"S.",
""
],
[
"Kokeyama",
"K.",
""
],
[
"Kondrashov",
"V.",
""
],
[
"Koranda",
"S.",
""
],
[
"Korth",
"W. Z.",
""
],
[
"Kowalska",
"I.",
""
],
[
"Kozak",
"D.",
""
],
[
"Kremin",
"A.",
""
],
[
"Kringel",
"V.",
""
],
[
"Krishnan",
"B.",
""
],
[
"Królak",
"A.",
""
],
[
"Kucharczyk",
"C.",
""
],
[
"Kudla",
"S.",
""
],
[
"Kuehn",
"G.",
""
],
[
"Kumar",
"A.",
""
],
[
"Kumar",
"D. Nand.",
""
],
[
"Kumar",
"P.",
""
],
[
"Kumar",
"R.",
""
],
[
"Kurdyumov",
"R.",
""
],
[
"Kwee",
"P.",
""
],
[
"Landry",
"M.",
""
],
[
"Lantz",
"B.",
""
],
[
"Larson",
"S.",
""
],
[
"Lasky",
"P. D.",
""
],
[
"Lawrie",
"C.",
""
],
[
"Lazzarini",
"A.",
""
],
[
"Leaci",
"P.",
""
],
[
"Lebigot",
"E. O.",
""
],
[
"Lee",
"C. -H.",
""
],
[
"Lee",
"H. K.",
""
],
[
"Lee",
"H. M.",
""
],
[
"Lee",
"J. J.",
""
],
[
"Lee",
"J.",
""
],
[
"Leonardi",
"M.",
""
],
[
"Leong",
"J. R.",
""
],
[
"Roux",
"A. L.",
""
],
[
"Leroy",
"N.",
""
],
[
"Letendre",
"N.",
""
],
[
"Levine",
"B.",
""
],
[
"Lewis",
"J. B.",
""
],
[
"Lhuillier",
"V.",
""
],
[
"Li",
"T. G. F.",
""
],
[
"Lin",
"A. C.",
""
],
[
"Littenberg",
"T. B.",
""
],
[
"Litvine",
"V.",
""
],
[
"Liu",
"F.",
""
],
[
"Liu",
"H.",
""
],
[
"Liu",
"Y.",
""
],
[
"Liu",
"Z.",
""
],
[
"Lloyd",
"D.",
""
],
[
"Lockerbie",
"N. A.",
""
],
[
"Lockett",
"V.",
""
],
[
"Lodhia",
"D.",
""
],
[
"Loew",
"K.",
""
],
[
"Logue",
"J.",
""
],
[
"Lombardi",
"A. L.",
""
],
[
"Lorenzini",
"M.",
""
],
[
"Loriette",
"V.",
""
],
[
"Lormand",
"M.",
""
],
[
"Losurdo",
"G.",
""
],
[
"Lough",
"J.",
""
],
[
"Luan",
"J.",
""
],
[
"Lubinski",
"M. J.",
""
],
[
"Lück",
"H.",
""
],
[
"Lundgren",
"A. P.",
""
],
[
"Macarthur",
"J.",
""
],
[
"Macdonald",
"E.",
""
],
[
"Machenschalk",
"B.",
""
],
[
"MacInnis",
"M.",
""
],
[
"Macleod",
"D. M.",
""
],
[
"Magana-Sandoval",
"F.",
""
],
[
"Mageswaran",
"M.",
""
],
[
"Mailand",
"K.",
""
],
[
"Majorana",
"E.",
""
],
[
"Maksimovic",
"I.",
""
],
[
"Malvezzi",
"V.",
""
],
[
"Man",
"N.",
""
],
[
"Manca",
"G. M.",
""
],
[
"Mandel",
"I.",
""
],
[
"Mandic",
"V.",
""
],
[
"Mangano",
"V.",
""
],
[
"Mantovani",
"M.",
""
],
[
"Marchesoni",
"F.",
""
],
[
"Marion",
"F.",
""
],
[
"Márka",
"S.",
""
],
[
"Márka",
"Z.",
""
],
[
"Markosyan",
"A.",
""
],
[
"Maros",
"E.",
""
],
[
"Marque",
"J.",
""
],
[
"Martelli",
"F.",
""
],
[
"Martellini",
"L.",
""
],
[
"Martin",
"I. W.",
""
],
[
"Martin",
"R. M.",
""
],
[
"Martini",
"G.",
""
],
[
"Martynov",
"D.",
""
],
[
"Marx",
"J. N.",
""
],
[
"Mason",
"K.",
""
],
[
"Masserot",
"A.",
""
],
[
"Massinger",
"T. J.",
""
],
[
"Matichard",
"F.",
""
],
[
"Matone",
"L.",
""
],
[
"Matzner",
"R. A.",
""
],
[
"Mavalvala",
"N.",
""
],
[
"May",
"G.",
""
],
[
"Mazumder",
"N.",
""
],
[
"Mazzolo",
"G.",
""
],
[
"McCarthy",
"R.",
""
],
[
"McClelland",
"D. E.",
""
],
[
"McGuire",
"S. C.",
""
],
[
"McIntyre",
"G.",
""
],
[
"McIver",
"J.",
""
],
[
"Meacher",
"D.",
""
],
[
"Meadors",
"G. D.",
""
],
[
"Mehmet",
"M.",
""
],
[
"Meidam",
"J.",
""
],
[
"Meier",
"T.",
""
],
[
"Melatos",
"A.",
""
],
[
"Mendell",
"G.",
""
],
[
"Mercer",
"R. A.",
""
],
[
"Meshkov",
"S.",
""
],
[
"Messenger",
"C.",
""
],
[
"Meyer",
"M. S.",
""
],
[
"Miao",
"H.",
""
],
[
"Michel",
"C.",
""
],
[
"Mikhailov",
"E.",
""
],
[
"Milano",
"L.",
""
],
[
"Miller",
"J.",
""
],
[
"Minenkov",
"Y.",
""
],
[
"Mingarelli",
"C. M. F.",
""
],
[
"Mitra",
"S.",
""
],
[
"Mitrofanov",
"V. P.",
""
],
[
"Mitselmakher",
"G.",
""
],
[
"Mittleman",
"R.",
""
],
[
"Moe",
"B.",
""
],
[
"Mohan",
"M.",
""
],
[
"Mohapatra",
"S. R. P.",
""
],
[
"Mokler",
"F.",
""
],
[
"Moraru",
"D.",
""
],
[
"Moreno",
"G.",
""
],
[
"Morgado",
"N.",
""
],
[
"Mori",
"T.",
""
],
[
"Morriss",
"S. R.",
""
],
[
"Mossavi",
"K.",
""
],
[
"Mours",
"B.",
""
],
[
"Mow-Lowry",
"C. M.",
""
],
[
"Mueller",
"C. L.",
""
],
[
"Mueller",
"G.",
""
],
[
"Mukherjee",
"S.",
""
],
[
"Mullavey",
"A.",
""
],
[
"Munch",
"J.",
""
],
[
"Murphy",
"D.",
""
],
[
"Murray",
"P. G.",
""
],
[
"Mytidis",
"A.",
""
],
[
"Nagy",
"M. F.",
""
],
[
"Nardecchia",
"I.",
""
],
[
"Nash",
"T.",
""
],
[
"Naticchioni",
"L.",
""
],
[
"Nayak",
"R.",
""
],
[
"Necula",
"V.",
""
],
[
"Neri",
"I.",
""
],
[
"Neri",
"M.",
""
],
[
"Newton",
"G.",
""
],
[
"Nguyen",
"T.",
""
],
[
"Nishida",
"E.",
""
],
[
"Nishizawa",
"A.",
""
],
[
"Nitz",
"A.",
""
],
[
"Nocera",
"F.",
""
],
[
"Nolting",
"D.",
""
],
[
"Normandin",
"M. E.",
""
],
[
"Nuttall",
"L. K.",
""
],
[
"Ochsner",
"E.",
""
],
[
"O'Dell",
"J.",
""
],
[
"Oelker",
"E.",
""
],
[
"Ogin",
"G. H.",
""
],
[
"Oh",
"J. J.",
""
],
[
"Oh",
"S. H.",
""
],
[
"Ohme",
"F.",
""
],
[
"Oppermann",
"P.",
""
],
[
"O'Reilly",
"B.",
""
],
[
"Larcher",
"W. Orteg.",
""
],
[
"O'Shaughnessy",
"R.",
""
],
[
"Osthelder",
"C.",
""
],
[
"Ottaway",
"D. J.",
""
],
[
"Ottens",
"R. S.",
""
],
[
"Ou",
"J.",
""
],
[
"Overmier",
"H.",
""
],
[
"Owen",
"B. J.",
""
],
[
"Padilla",
"C.",
""
],
[
"Pai",
"A.",
""
],
[
"Palomba",
"C.",
""
],
[
"Pan",
"Y.",
""
],
[
"Pankow",
"C.",
""
],
[
"Paoletti",
"F.",
""
],
[
"Paoletti",
"R.",
""
],
[
"Paris",
"H.",
""
],
[
"Pasqualetti",
"A.",
""
],
[
"Passaquieti",
"R.",
""
],
[
"Passuello",
"D.",
""
],
[
"Pedraza",
"M.",
""
],
[
"Peiris",
"P.",
""
],
[
"Penn",
"S.",
""
],
[
"Perreca",
"A.",
""
],
[
"Phelps",
"M.",
""
],
[
"Pichot",
"M.",
""
],
[
"Pickenpack",
"M.",
""
],
[
"Piergiovanni",
"F.",
""
],
[
"Pierro",
"V.",
""
],
[
"Pinard",
"L.",
""
],
[
"Pindor",
"B.",
""
],
[
"Pinto",
"I. M.",
""
],
[
"Pitkin",
"M.",
""
],
[
"Poeld",
"J.",
""
],
[
"Poggiani",
"R.",
""
],
[
"Poole",
"V.",
""
],
[
"Postiglione",
"F.",
""
],
[
"Poux",
"C.",
""
],
[
"Predoi",
"V.",
""
],
[
"Prestegard",
"T.",
""
],
[
"Price",
"L. R.",
""
],
[
"Prijatelj",
"M.",
""
],
[
"Privitera",
"S.",
""
],
[
"Prodi",
"G. A.",
""
],
[
"Prokhorov",
"L.",
""
],
[
"Puncken",
"O.",
""
],
[
"Punturo",
"M.",
""
],
[
"Puppo",
"P.",
""
],
[
"Quetschke",
"V.",
""
],
[
"Quintero",
"E.",
""
],
[
"Quitzow-James",
"R.",
""
],
[
"Raab",
"F. J.",
""
],
[
"Rabeling",
"D. S.",
""
],
[
"Rácz",
"I.",
""
],
[
"Radkins",
"H.",
""
],
[
"Raffai",
"P.",
""
],
[
"Raja",
"S.",
""
],
[
"Rajalakshmi",
"G.",
""
],
[
"Rakhmanov",
"M.",
""
],
[
"Ramet",
"C.",
""
],
[
"Rapagnani",
"P.",
""
],
[
"Raymond",
"V.",
""
],
[
"Re",
"V.",
""
],
[
"Reed",
"C. M.",
""
],
[
"Reed",
"T.",
""
],
[
"Regimbau",
"T.",
""
],
[
"Reid",
"S.",
""
],
[
"Reitze",
"D. H.",
""
],
[
"Ricci",
"F.",
""
],
[
"Riesen",
"R.",
""
],
[
"Riles",
"K.",
""
],
[
"Robertson",
"N. A.",
""
],
[
"Robinet",
"F.",
""
],
[
"Rocchi",
"A.",
""
],
[
"Roddy",
"S.",
""
],
[
"Rodriguez",
"C.",
""
],
[
"Rodruck",
"M.",
""
],
[
"Roever",
"C.",
""
],
[
"Rolland",
"L.",
""
],
[
"Rollins",
"J. G.",
""
],
[
"Romano",
"J. D.",
""
],
[
"Romano",
"R.",
""
],
[
"Romanov",
"G.",
""
],
[
"Romie",
"J. H.",
""
],
[
"Rosińska",
"D.",
""
],
[
"Rowan",
"S.",
""
],
[
"Rüdiger",
"A.",
""
],
[
"Ruggi",
"P.",
""
],
[
"Ryan",
"K.",
""
],
[
"Salemi",
"F.",
""
],
[
"Sammut",
"L.",
""
],
[
"Sandberg",
"V.",
""
],
[
"Sanders",
"J.",
""
],
[
"Sannibale",
"V.",
""
],
[
"Santiago-Prieto",
"I.",
""
],
[
"Saracco",
"E.",
""
],
[
"Sassolas",
"B.",
""
],
[
"Sathyaprakash",
"B. S.",
""
],
[
"Saulson",
"P. R.",
""
],
[
"Savage",
"R.",
""
],
[
"Schilling",
"R.",
""
],
[
"Schnabel",
"R.",
""
],
[
"Schofield",
"R. M. S.",
""
],
[
"Schreiber",
"E.",
""
],
[
"Schuette",
"D.",
""
],
[
"Schulz",
"B.",
""
],
[
"Schutz",
"B. F.",
""
],
[
"Schwinberg",
"P.",
""
],
[
"Scott",
"J.",
""
],
[
"Scott",
"S. M.",
""
],
[
"Seifert",
"F.",
""
],
[
"Sellers",
"D.",
""
],
[
"Sengupta",
"A. S.",
""
],
[
"Sentenac",
"D.",
""
],
[
"Sequino",
"V.",
""
],
[
"Sergeev",
"A.",
""
],
[
"Shaddock",
"D.",
""
],
[
"Shah",
"S.",
""
],
[
"Shahriar",
"M. S.",
""
],
[
"Shaltev",
"M.",
""
],
[
"Shapiro",
"B.",
""
],
[
"Shawhan",
"P.",
""
],
[
"Shoemaker",
"D. H.",
""
],
[
"Sidery",
"T. L.",
""
],
[
"Siellez",
"K.",
""
],
[
"Siemens",
"X.",
""
],
[
"Sigg",
"D.",
""
],
[
"Simakov",
"D.",
""
],
[
"Singer",
"A.",
""
],
[
"Singer",
"L.",
""
],
[
"Sintes",
"A. M.",
""
],
[
"Skelton",
"G. R.",
""
],
[
"Slagmolen",
"B. J. J.",
""
],
[
"Slutsky",
"J.",
""
],
[
"Smith",
"J. R.",
""
],
[
"Smith",
"M. R.",
""
],
[
"Smith",
"R. J. E.",
""
],
[
"Smith-Lefebvre",
"N. D.",
""
],
[
"Soden",
"K.",
""
],
[
"Son",
"E. J.",
""
],
[
"Sorazu",
"B.",
""
],
[
"Souradeep",
"T.",
""
],
[
"Sperandio",
"L.",
""
],
[
"Staley",
"A.",
""
],
[
"Steinert",
"E.",
""
],
[
"Steinlechner",
"J.",
""
],
[
"Steinlechner",
"S.",
""
],
[
"Steplewski",
"S.",
""
],
[
"Stevens",
"D.",
""
],
[
"Stochino",
"A.",
""
],
[
"Stone",
"R.",
""
],
[
"Strain",
"K. A.",
""
],
[
"Straniero",
"N.",
""
],
[
"Strigin",
"S.",
""
],
[
"Stroeer",
"A. S.",
""
],
[
"Sturani",
"R.",
""
],
[
"Stuver",
"A. L.",
""
],
[
"Summerscales",
"T. Z.",
""
],
[
"Susmithan",
"S.",
""
],
[
"Sutton",
"P. J.",
""
],
[
"Swinkels",
"B.",
""
],
[
"Szeifert",
"G.",
""
],
[
"Tacca",
"M.",
""
],
[
"Talukder",
"D.",
""
],
[
"Tang",
"L.",
""
],
[
"Tanner",
"D. B.",
""
],
[
"Tarabrin",
"S. P.",
""
],
[
"Taylor",
"R.",
""
],
[
"Braack",
"A. P. M. te.",
""
],
[
"Thirugnanasambandam",
"M. P.",
""
],
[
"Thomas",
"M.",
""
],
[
"Thomas",
"P.",
""
],
[
"Thorne",
"K. A.",
""
],
[
"Thorne",
"K. S.",
""
],
[
"Thrane",
"E.",
""
],
[
"Tiwari",
"V.",
""
],
[
"Tokmakov",
"K. V.",
""
],
[
"Tomlinson",
"C.",
""
],
[
"Toncelli",
"A.",
""
],
[
"Tonelli",
"M.",
""
],
[
"Torre",
"O.",
""
],
[
"Torres",
"C. V.",
""
],
[
"Torrie",
"C. I.",
""
],
[
"Travasso",
"F.",
""
],
[
"Traylor",
"G.",
""
],
[
"Tse",
"M.",
""
],
[
"Ugolini",
"D.",
""
],
[
"Unnikrishnan",
"C. S.",
""
],
[
"Vahlbruch",
"H.",
""
],
[
"Vajente",
"G.",
""
],
[
"Vallisneri",
"M.",
""
],
[
"Brand",
"J. F. J. va. de.",
""
],
[
"Broeck",
"C. Va. De.",
""
],
[
"Putten",
"S. va. de.",
""
],
[
"Sluys",
"M. V. va. de.",
""
],
[
"Heijningen",
"J. va.",
""
],
[
"Veggel",
"A. A. va.",
""
],
[
"Vass",
"S.",
""
],
[
"Vasúth",
"M.",
""
],
[
"Vaulin",
"R.",
""
],
[
"Vecchio",
"A.",
""
],
[
"Vedovato",
"G.",
""
],
[
"Veitch",
"P. J.",
""
],
[
"Veitch",
"J.",
""
],
[
"Venkateswara",
"K.",
""
],
[
"Verkindt",
"D.",
""
],
[
"Verma",
"S.",
""
],
[
"Vetrano",
"F.",
""
],
[
"Viceré",
"A.",
""
],
[
"Vincent-Finley",
"R.",
""
],
[
"Vinet",
"J. -Y.",
""
],
[
"Vitale",
"S.",
""
],
[
"Vitale",
"S.",
""
],
[
"Vlcek",
"B.",
""
],
[
"Vo",
"T.",
""
],
[
"Vocca",
"H.",
""
],
[
"Vorvick",
"C.",
""
],
[
"Vousden",
"W. D.",
""
],
[
"Vrinceanu",
"D.",
""
],
[
"Vyachanin",
"S. P.",
""
],
[
"Wade",
"A.",
""
],
[
"Wade",
"L.",
""
],
[
"Wade",
"M.",
""
],
[
"Waldman",
"S. J.",
""
],
[
"Walker",
"M.",
""
],
[
"Wallace",
"L.",
""
],
[
"Wan",
"Y.",
""
],
[
"Wang",
"J.",
""
],
[
"Wang",
"M.",
""
],
[
"Wang",
"X.",
""
],
[
"Wanner",
"A.",
""
],
[
"Ward",
"R. L.",
""
],
[
"Was",
"M.",
""
],
[
"Weaver",
"B.",
""
],
[
"Wei",
"L. -W.",
""
],
[
"Weinert",
"M.",
""
],
[
"Weinstein",
"A. J.",
""
],
[
"Weiss",
"R.",
""
],
[
"Welborn",
"T.",
""
],
[
"Wen",
"L.",
""
],
[
"Wessels",
"P.",
""
],
[
"West",
"M.",
""
],
[
"Westphal",
"T.",
""
],
[
"Wette",
"K.",
""
],
[
"Whelan",
"J. T.",
""
],
[
"White",
"D. J.",
""
],
[
"Whiting",
"B. F.",
""
],
[
"Wibowo",
"S.",
""
],
[
"Wiesner",
"K.",
""
],
[
"Wilkinson",
"C.",
""
],
[
"Williams",
"L.",
""
],
[
"Williams",
"R.",
""
],
[
"Williams",
"T.",
""
],
[
"Willis",
"J. L.",
""
],
[
"Willke",
"B.",
""
],
[
"Wimmer",
"M.",
""
],
[
"Winkelmann",
"L.",
""
],
[
"Winkler",
"W.",
""
],
[
"Wipf",
"C. C.",
""
],
[
"Wittel",
"H.",
""
],
[
"Woan",
"G.",
""
],
[
"Worden",
"J.",
""
],
[
"Yablon",
"J.",
""
],
[
"Yakushin",
"I.",
""
],
[
"Yamamoto",
"H.",
""
],
[
"Yancey",
"C. C.",
""
],
[
"Yang",
"H.",
""
],
[
"Yeaton-Massey",
"D.",
""
],
[
"Yoshida",
"S.",
""
],
[
"Yum",
"H.",
""
],
[
"Yvert",
"M.",
""
],
[
"Zadrożny",
"A.",
""
],
[
"Zanolin",
"M.",
""
],
[
"Zendri",
"J. -P.",
""
],
[
"Zhang",
"F.",
""
],
[
"Zhang",
"L.",
""
],
[
"Zhao",
"C.",
""
],
[
"Zhu",
"H.",
""
],
[
"Zhu",
"X. J.",
""
],
[
"Zotov",
"N.",
""
],
[
"Zucker",
"M. E.",
""
],
[
"Zweizig",
"J.",
""
]
] | Searches for a stochastic gravitational-wave background (SGWB) using terrestrial detectors typically involve cross-correlating data from pairs of detectors. The sensitivity of such cross-correlation analyses depends, among other things, on the separation between the two detectors: the smaller the separation, the better the sensitivity. Hence, a co-located detector pair is more sensitive to a gravitational-wave background than a non-co-located detector pair. However, co-located detectors are also expected to suffer from correlated noise from instrumental and environmental effects that could contaminate the measurement of the background. Hence, methods to identify and mitigate the effects of correlated noise are necessary to achieve the potential increase in sensitivity of co-located detectors. Here we report on the first SGWB analysis using the two LIGO Hanford detectors and address the complications arising from correlated environmental noise. We apply correlated noise identification and mitigation techniques to data taken by the two LIGO Hanford detectors, H1 and H2, during LIGO's fifth science run. At low frequencies, 40 - 460 Hz, we are unable to sufficiently mitigate the correlated noise to a level where we may confidently measure or bound the stochastic gravitational-wave signal. However, at high frequencies, 460-1000 Hz, these techniques are sufficient to set a $95%$ confidence level (C.L.) upper limit on the gravitational-wave energy density of \Omega(f)<7.7 x 10^{-4} (f/ 900 Hz)^3, which improves on the previous upper limit by a factor of $\sim 180$. In doing so, we demonstrate techniques that will be useful for future searches using advanced detectors, where correlated noise (e.g., from global magnetic fields) may affect even widely separated detectors. |
0710.3680 | Piotr T. Chru\'sciel | Piotr T. Chrusciel | Mass and angular-momentum inequalities for axi-symmetric initial data
sets I. Positivity of mass | 33 pages in A4 | AnnalsPhys.323:2566-2590,2008 | 10.1016/j.aop.2007.12.010 | null | gr-qc | null | We extend the validity of Brill's axisymmetric positive energy theorem to all
asymptotically flat initial data sets with positive scalar curvature on simply
connected manifolds.
| [
{
"created": "Fri, 19 Oct 2007 11:50:41 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Chrusciel",
"Piotr T.",
""
]
] | We extend the validity of Brill's axisymmetric positive energy theorem to all asymptotically flat initial data sets with positive scalar curvature on simply connected manifolds. |
2011.08770 | Nikos Chatzifotis | Nikos Chatzifotis, George Koutsoumbas, Eleftherios Papantonopoulos | Formation of Bound States of scalar fields in AdS-asymptotic Wormholes | 22 pages, 10 figures, References updated, Minor changes | Phys. Rev. D 104, 024039 (2021) | 10.1103/PhysRevD.104.024039 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the Wentzel-Kramers-Brillouin (WKB) approximation to study the
formation and propagation of bound states in the vicinity of a wormhole in the
non-minimal derivative coupling theory of gravity. The wormhole throat connects
two Anti-de Sitter spacetimes. We show that when the scalar field lies in high
orbital states, the corresponding potential has potential barriers that block
the passage of a classical field. We investigate the behaviour of the bound
states trapped in the potential wells and provide the flow between the two AdS
regions.
| [
{
"created": "Tue, 17 Nov 2020 16:56:57 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Nov 2020 19:47:31 GMT",
"version": "v2"
},
{
"created": "Tue, 1 Dec 2020 11:33:41 GMT",
"version": "v3"
},
{
"created": "Thu, 13 May 2021 10:07:08 GMT",
"version": "v4"
}
] | 2021-08-06 | [
[
"Chatzifotis",
"Nikos",
""
],
[
"Koutsoumbas",
"George",
""
],
[
"Papantonopoulos",
"Eleftherios",
""
]
] | We use the Wentzel-Kramers-Brillouin (WKB) approximation to study the formation and propagation of bound states in the vicinity of a wormhole in the non-minimal derivative coupling theory of gravity. The wormhole throat connects two Anti-de Sitter spacetimes. We show that when the scalar field lies in high orbital states, the corresponding potential has potential barriers that block the passage of a classical field. We investigate the behaviour of the bound states trapped in the potential wells and provide the flow between the two AdS regions. |
gr-qc/0301036 | Jean-Philippe Uzan | Nathalie Deruelle (GReCO, IAP, Paris) | Linearized gravity on branes: from Newton's law to cosmological
perturbations | 11 pages, Tex, proceedings of the talk presented at the conference
ERE 2002 held in Menorca in september 2002 | null | null | null | gr-qc astro-ph hep-th | null | We review here how Newton's law can be approximately recovered in the simple,
"paradigmatic", case of a flat $Z_2$-symmetric brane in a 5-D anti-de Sitter
bulk. We then comment on the difficulties encountered so far in extending this
analysis to cosmological perturbations on a Robertson-Walker brane.
| [
{
"created": "Fri, 10 Jan 2003 12:19:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Deruelle",
"Nathalie",
"",
"GReCO, IAP, Paris"
]
] | We review here how Newton's law can be approximately recovered in the simple, "paradigmatic", case of a flat $Z_2$-symmetric brane in a 5-D anti-de Sitter bulk. We then comment on the difficulties encountered so far in extending this analysis to cosmological perturbations on a Robertson-Walker brane. |
0708.1460 | Herrera Ramon Dr | Sergio del Campo and Ramon Herrera | Warm inflation in the DGP brane-world model | 15 pages and 1 figure. Accepted for publication in Phys. Lett. B | Phys.Lett.B653:122-128,2007 | 10.1016/j.physletb.2007.08.007 | null | gr-qc astro-ph hep-th | null | Warm inflationary universe models on a warped Dvali-Gabadadze-Porrati brane
are studied. General conditions required for these models to be realizable are
derived and discussed. By using an effective exponential potential we develop
models for constant and variable dissipation coefficient ratio
$r=\frac{\Gamma}{3 H}$. We use recent astronomical observations for
constraining the parameters appearing in our models.
| [
{
"created": "Fri, 10 Aug 2007 15:21:22 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"del Campo",
"Sergio",
""
],
[
"Herrera",
"Ramon",
""
]
] | Warm inflationary universe models on a warped Dvali-Gabadadze-Porrati brane are studied. General conditions required for these models to be realizable are derived and discussed. By using an effective exponential potential we develop models for constant and variable dissipation coefficient ratio $r=\frac{\Gamma}{3 H}$. We use recent astronomical observations for constraining the parameters appearing in our models. |
1003.1379 | Manuel Hohmann | Manuel Hohmann and Mattias N. R. Wohlfarth | Repulsive gravity model for dark energy | 16 pages, 2 figures; journal version | Phys.Rev.D81:104006,2010 | 10.1103/PhysRevD.81.104006 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a multimetric gravity theory containing N >= 3 copies of
standard model matter and a corresponding number of metrics. In the Newtonian
limit, this theory generates attractive gravitational forces within each matter
sector, and repulsive forces of the same strength between matter from different
sectors. This result demonstrates that the recently proven no-go theorem that
forbids gravity theories of this type in N = 2 cannot be extended beyond the
bimetric case. We apply our theory to cosmology and show that the repulsion
between different types of matter may induce the observed accelerating
expansion of the universe. In this way dark energy can be explained simply by
dark copies of the well-understood standard model.
| [
{
"created": "Sat, 6 Mar 2010 12:34:34 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Jul 2010 07:31:34 GMT",
"version": "v2"
}
] | 2010-07-07 | [
[
"Hohmann",
"Manuel",
""
],
[
"Wohlfarth",
"Mattias N. R.",
""
]
] | We construct a multimetric gravity theory containing N >= 3 copies of standard model matter and a corresponding number of metrics. In the Newtonian limit, this theory generates attractive gravitational forces within each matter sector, and repulsive forces of the same strength between matter from different sectors. This result demonstrates that the recently proven no-go theorem that forbids gravity theories of this type in N = 2 cannot be extended beyond the bimetric case. We apply our theory to cosmology and show that the repulsion between different types of matter may induce the observed accelerating expansion of the universe. In this way dark energy can be explained simply by dark copies of the well-understood standard model. |
1908.00802 | Oliver Buchmueller | Yousef Abou El-Neaj, Cristiano Alpigiani, Sana Amairi-Pyka, Henrique
Araujo, Antun Balaz, Angelo Bassi, Lars Bathe-Peters, Baptiste Battelier,
Aleksandar Belic, Elliot Bentine, Jose Bernabeu, Andrea Bertoldi, Robert
Bingham, Diego Blas, Vasiliki Bolpasi, Kai Bongs, Sougato Bose, Philippe
Bouyer, Themis Bowcock, William Bowden, Oliver Buchmueller, Clare Burrage,
Xavier Calmet, Benjamin Canuel, Laurentiu-Ioan Caramete, Andrew Carroll,
Giancarlo Cella, Vassilis Charmandaris, Swapan Chattopadhyay, Xuzong Chen,
Maria Luisa Chiofalo, Jonathon Coleman, Joseph Cotter, Yanou Cui, Andrei
Derevianko, Albert De Roeck, Goran Djordjevic, Peter Dornan, Michael Doser,
Ioannis Drougkakis, Jacob Dunningham, Ioana Dutan, Sajan Easo, Gedminas
Elertas, John Ellis, Mai El Sawy, Farida Fassi, Daniel Felea, Chen-Hao Feng,
Robert Flack, Chris Foot, Ivette Fuentes, Naceur Gaaloul, Alexandre Gauguet,
Remi Geiger, Valerie Gibson, Gian Giudice, Jon Goldwin, Oleg Grachov, Peter
W. Graham, Dario Grasso, Maurits van der Grinten, Mustafa Gundogan, Martin G.
Haehnelt, Tiffany Harte, Aurelien Hees, Richard Hobson, Bodil Holst, Jason
Hogan, Mark Kasevich, Bradley J. Kavanagh, Wolf von Klitzing, Tim Kovachy,
Benjamin Krikler, Markus Krutzik, Marek Lewicki, Yu-Hung Lien, Miaoyuan Liu,
Giuseppe Gaetano Luciano, Alain Magnon, Mohammed Mahmoud, Sarah Malik,
Christopher McCabe, Jeremiah Mitchell, Julia Pahl, Debapriya Pal, Saurabh
Pandey, Dimitris Papazoglou, Mauro Paternostro, Bjoern Penning, Achim Peters,
Marco Prevedelli, Vishnupriya Puthiya-Veettil, John Quenby, Ernst Rasel, Sean
Ravenhall, Haifa Rejeb Sfar, Jack Ringwood, Albert Roura, Dylan Sabulsky,
Muhammed Sameed, Ben Sauer, Stefan Alaric Schaffer, Stephan Schiller,
Vladimir Schkolnik, Dennis Schlippert, Christian Schubert, Armin Shayeghi,
Ian Shipsey, Carla Signorini, Marcelle Soares-Santos, Fiodor Sorrentino,
Yajpal Singh, Timothy Sumner, Konstantinos Tassis, Silvia Tentindo, Guglielmo
Maria Tino, Jonathan N. Tinsley, James Unwin, Tristan Valenzuela, Georgios
Vasilakis, Ville Vaskonen, Christian Vogt, Alex Webber-Date, Andre
Wenzlawski, Patrick Windpassinger, Marian Woltmann, Michael Holynski, Efe
Yazgan, Ming-Sheng Zhan, Xinhao Zou, Jure Zupan | AEDGE: Atomic Experiment for Dark Matter and Gravity Exploration in
Space | V2 -- added support authors | EPJ Quantum Technol. 7, 6 (2020) | 10.1140/epjqt/s40507-020-0080-0 | KCL-PH-TH/2019-65, CERN-TH-2019-126 | gr-qc astro-ph.IM hep-ex hep-ph physics.atom-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose in this White Paper a concept for a space experiment using cold
atoms to search for ultra-light dark matter, and to detect gravitational waves
in the frequency range between the most sensitive ranges of LISA and the
terrestrial LIGO/Virgo/KAGRA/INDIGO experiments. This interdisciplinary
experiment, called Atomic Experiment for Dark Matter and Gravity Exploration
(AEDGE), will also complement other planned searches for dark matter, and
exploit synergies with other gravitational wave detectors. We give examples of
the extended range of sensitivity to ultra-light dark matter offered by AEDGE,
and how its gravitational-wave measurements could explore the assembly of
super-massive black holes, first-order phase transitions in the early universe
and cosmic strings. AEDGE will be based upon technologies now being developed
for terrestrial experiments using cold atoms, and will benefit from the space
experience obtained with, e.g., LISA and cold atom experiments in microgravity.
This paper is based on a submission (v1) in response to the Call for White
Papers for the Voyage 2050 long-term plan in the ESA Science Programme. ESA
limited the number of White Paper authors to 30. However, in this version (v2)
we have welcomed as supporting authors participants in the Workshop on Atomic
Experiments for Dark Matter and Gravity Exploration held at CERN: ({\tt
https://indico.cern.ch/event/830432/}), as well as other interested scientists,
and have incorporated additional material.
| [
{
"created": "Fri, 2 Aug 2019 11:02:03 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Oct 2019 10:19:46 GMT",
"version": "v2"
}
] | 2020-07-22 | [
[
"El-Neaj",
"Yousef Abou",
""
],
[
"Alpigiani",
"Cristiano",
""
],
[
"Amairi-Pyka",
"Sana",
""
],
[
"Araujo",
"Henrique",
""
],
[
"Balaz",
"Antun",
""
],
[
"Bassi",
"Angelo",
""
],
[
"Bathe-Peters",
"Lars",
""
],
[
"Battelier",
"Baptiste",
""
],
[
"Belic",
"Aleksandar",
""
],
[
"Bentine",
"Elliot",
""
],
[
"Bernabeu",
"Jose",
""
],
[
"Bertoldi",
"Andrea",
""
],
[
"Bingham",
"Robert",
""
],
[
"Blas",
"Diego",
""
],
[
"Bolpasi",
"Vasiliki",
""
],
[
"Bongs",
"Kai",
""
],
[
"Bose",
"Sougato",
""
],
[
"Bouyer",
"Philippe",
""
],
[
"Bowcock",
"Themis",
""
],
[
"Bowden",
"William",
""
],
[
"Buchmueller",
"Oliver",
""
],
[
"Burrage",
"Clare",
""
],
[
"Calmet",
"Xavier",
""
],
[
"Canuel",
"Benjamin",
""
],
[
"Caramete",
"Laurentiu-Ioan",
""
],
[
"Carroll",
"Andrew",
""
],
[
"Cella",
"Giancarlo",
""
],
[
"Charmandaris",
"Vassilis",
""
],
[
"Chattopadhyay",
"Swapan",
""
],
[
"Chen",
"Xuzong",
""
],
[
"Chiofalo",
"Maria Luisa",
""
],
[
"Coleman",
"Jonathon",
""
],
[
"Cotter",
"Joseph",
""
],
[
"Cui",
"Yanou",
""
],
[
"Derevianko",
"Andrei",
""
],
[
"De Roeck",
"Albert",
""
],
[
"Djordjevic",
"Goran",
""
],
[
"Dornan",
"Peter",
""
],
[
"Doser",
"Michael",
""
],
[
"Drougkakis",
"Ioannis",
""
],
[
"Dunningham",
"Jacob",
""
],
[
"Dutan",
"Ioana",
""
],
[
"Easo",
"Sajan",
""
],
[
"Elertas",
"Gedminas",
""
],
[
"Ellis",
"John",
""
],
[
"Sawy",
"Mai El",
""
],
[
"Fassi",
"Farida",
""
],
[
"Felea",
"Daniel",
""
],
[
"Feng",
"Chen-Hao",
""
],
[
"Flack",
"Robert",
""
],
[
"Foot",
"Chris",
""
],
[
"Fuentes",
"Ivette",
""
],
[
"Gaaloul",
"Naceur",
""
],
[
"Gauguet",
"Alexandre",
""
],
[
"Geiger",
"Remi",
""
],
[
"Gibson",
"Valerie",
""
],
[
"Giudice",
"Gian",
""
],
[
"Goldwin",
"Jon",
""
],
[
"Grachov",
"Oleg",
""
],
[
"Graham",
"Peter W.",
""
],
[
"Grasso",
"Dario",
""
],
[
"van der Grinten",
"Maurits",
""
],
[
"Gundogan",
"Mustafa",
""
],
[
"Haehnelt",
"Martin G.",
""
],
[
"Harte",
"Tiffany",
""
],
[
"Hees",
"Aurelien",
""
],
[
"Hobson",
"Richard",
""
],
[
"Holst",
"Bodil",
""
],
[
"Hogan",
"Jason",
""
],
[
"Kasevich",
"Mark",
""
],
[
"Kavanagh",
"Bradley J.",
""
],
[
"von Klitzing",
"Wolf",
""
],
[
"Kovachy",
"Tim",
""
],
[
"Krikler",
"Benjamin",
""
],
[
"Krutzik",
"Markus",
""
],
[
"Lewicki",
"Marek",
""
],
[
"Lien",
"Yu-Hung",
""
],
[
"Liu",
"Miaoyuan",
""
],
[
"Luciano",
"Giuseppe Gaetano",
""
],
[
"Magnon",
"Alain",
""
],
[
"Mahmoud",
"Mohammed",
""
],
[
"Malik",
"Sarah",
""
],
[
"McCabe",
"Christopher",
""
],
[
"Mitchell",
"Jeremiah",
""
],
[
"Pahl",
"Julia",
""
],
[
"Pal",
"Debapriya",
""
],
[
"Pandey",
"Saurabh",
""
],
[
"Papazoglou",
"Dimitris",
""
],
[
"Paternostro",
"Mauro",
""
],
[
"Penning",
"Bjoern",
""
],
[
"Peters",
"Achim",
""
],
[
"Prevedelli",
"Marco",
""
],
[
"Puthiya-Veettil",
"Vishnupriya",
""
],
[
"Quenby",
"John",
""
],
[
"Rasel",
"Ernst",
""
],
[
"Ravenhall",
"Sean",
""
],
[
"Sfar",
"Haifa Rejeb",
""
],
[
"Ringwood",
"Jack",
""
],
[
"Roura",
"Albert",
""
],
[
"Sabulsky",
"Dylan",
""
],
[
"Sameed",
"Muhammed",
""
],
[
"Sauer",
"Ben",
""
],
[
"Schaffer",
"Stefan Alaric",
""
],
[
"Schiller",
"Stephan",
""
],
[
"Schkolnik",
"Vladimir",
""
],
[
"Schlippert",
"Dennis",
""
],
[
"Schubert",
"Christian",
""
],
[
"Shayeghi",
"Armin",
""
],
[
"Shipsey",
"Ian",
""
],
[
"Signorini",
"Carla",
""
],
[
"Soares-Santos",
"Marcelle",
""
],
[
"Sorrentino",
"Fiodor",
""
],
[
"Singh",
"Yajpal",
""
],
[
"Sumner",
"Timothy",
""
],
[
"Tassis",
"Konstantinos",
""
],
[
"Tentindo",
"Silvia",
""
],
[
"Tino",
"Guglielmo Maria",
""
],
[
"Tinsley",
"Jonathan N.",
""
],
[
"Unwin",
"James",
""
],
[
"Valenzuela",
"Tristan",
""
],
[
"Vasilakis",
"Georgios",
""
],
[
"Vaskonen",
"Ville",
""
],
[
"Vogt",
"Christian",
""
],
[
"Webber-Date",
"Alex",
""
],
[
"Wenzlawski",
"Andre",
""
],
[
"Windpassinger",
"Patrick",
""
],
[
"Woltmann",
"Marian",
""
],
[
"Holynski",
"Michael",
""
],
[
"Yazgan",
"Efe",
""
],
[
"Zhan",
"Ming-Sheng",
""
],
[
"Zou",
"Xinhao",
""
],
[
"Zupan",
"Jure",
""
]
] | We propose in this White Paper a concept for a space experiment using cold atoms to search for ultra-light dark matter, and to detect gravitational waves in the frequency range between the most sensitive ranges of LISA and the terrestrial LIGO/Virgo/KAGRA/INDIGO experiments. This interdisciplinary experiment, called Atomic Experiment for Dark Matter and Gravity Exploration (AEDGE), will also complement other planned searches for dark matter, and exploit synergies with other gravitational wave detectors. We give examples of the extended range of sensitivity to ultra-light dark matter offered by AEDGE, and how its gravitational-wave measurements could explore the assembly of super-massive black holes, first-order phase transitions in the early universe and cosmic strings. AEDGE will be based upon technologies now being developed for terrestrial experiments using cold atoms, and will benefit from the space experience obtained with, e.g., LISA and cold atom experiments in microgravity. This paper is based on a submission (v1) in response to the Call for White Papers for the Voyage 2050 long-term plan in the ESA Science Programme. ESA limited the number of White Paper authors to 30. However, in this version (v2) we have welcomed as supporting authors participants in the Workshop on Atomic Experiments for Dark Matter and Gravity Exploration held at CERN: ({\tt https://indico.cern.ch/event/830432/}), as well as other interested scientists, and have incorporated additional material. |
gr-qc/0302027 | Yuri N. Obukhov | Yuri N. Obukhov, Thoralf Chrobok, and Mike Scherfner | Rotation in string cosmology | 15 pages, 1 figure, Revtex, to appear in Class. Quantum Grav | Class.Quant.Grav.20:1103-1114,2003 | 10.1088/0264-9381/20/6/305 | null | gr-qc astro-ph hep-th | null | We describe exact cosmological solutions with rotation and expansion in the
low-energy effective string theory. These models are spatially homogeneous
(closed Bianchi type IX) and they belong to the family of shear-free metrics
which are causal (no closed timelike curves are allowed), admit no parallax
effects and do not disturb the isotropy of the background radiation. The
dilaton and the axion fields are nontrivial, in general, and we consider both
cases with and without the central charge (effective cosmological constant).
| [
{
"created": "Sun, 9 Feb 2003 12:15:24 GMT",
"version": "v1"
}
] | 2010-11-19 | [
[
"Obukhov",
"Yuri N.",
""
],
[
"Chrobok",
"Thoralf",
""
],
[
"Scherfner",
"Mike",
""
]
] | We describe exact cosmological solutions with rotation and expansion in the low-energy effective string theory. These models are spatially homogeneous (closed Bianchi type IX) and they belong to the family of shear-free metrics which are causal (no closed timelike curves are allowed), admit no parallax effects and do not disturb the isotropy of the background radiation. The dilaton and the axion fields are nontrivial, in general, and we consider both cases with and without the central charge (effective cosmological constant). |
0902.2360 | Kirill Bronnikov | Kirill A. Bronnikov, Jos\'e P. S. Lemos | Cylindrical wormholes | 13 pages, no figures. Substantial changes, a no-go theorem and 2
references added | Phys.Rev.D79:104019,2009 | 10.1103/PhysRevD.79.104019 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that the existence of static, cylindrically symmetric wormholes
does not require violation of the weak or null energy conditions near the
throat, and cylindrically symmetric wormhole geometries can appear with less
exotic sources than wormholes whose throats have a spherical topology. Examples
of exact wormhole solutions are given with scalar, spinor and electromagnetic
fields as sources, and these fields are not necessarily phantom. In particular,
there are wormhole solutions for a massless, minimally coupled scalar field in
the presence of a negative cosmological constant, and for an azimuthal Maxwell
electromagnetic field. All these solutions are not asymptotically flat. A no-go
theorem is proved, according to which a flat (or string) asymptotic behavior on
both sides of a cylindrical wormhole throat is impossible if the energy density
of matter is everywhere nonnegative.
| [
{
"created": "Fri, 13 Feb 2009 17:53:23 GMT",
"version": "v1"
},
{
"created": "Sat, 14 Feb 2009 05:55:27 GMT",
"version": "v2"
},
{
"created": "Tue, 24 Feb 2009 22:30:44 GMT",
"version": "v3"
}
] | 2009-07-30 | [
[
"Bronnikov",
"Kirill A.",
""
],
[
"Lemos",
"José P. S.",
""
]
] | It is shown that the existence of static, cylindrically symmetric wormholes does not require violation of the weak or null energy conditions near the throat, and cylindrically symmetric wormhole geometries can appear with less exotic sources than wormholes whose throats have a spherical topology. Examples of exact wormhole solutions are given with scalar, spinor and electromagnetic fields as sources, and these fields are not necessarily phantom. In particular, there are wormhole solutions for a massless, minimally coupled scalar field in the presence of a negative cosmological constant, and for an azimuthal Maxwell electromagnetic field. All these solutions are not asymptotically flat. A no-go theorem is proved, according to which a flat (or string) asymptotic behavior on both sides of a cylindrical wormhole throat is impossible if the energy density of matter is everywhere nonnegative. |
gr-qc/0303112 | Frank Potter | Howard G. Preston and Franklin Potter | Exploring Large-scale Gravitational Quantization without h-bar in
Planetary Systems, Galaxies, and the Universe | 16 pages | null | null | null | gr-qc | null | We explore a theory of large-scale gravitational quantization, using the
general relativistic Hamilton-Jacobi equation to create quantization conditions
via a new scalar wave equation dependent upon the total mass and the total
vector angular momentum only. Instead of h-bar, a local invariant quantity
proportional to the total angular momentum dictates the quantization
conditions. In the Schwarzschild metric the theory predicts eigenstates with
quantized energy per mass and angular momentum per mass. We find excellent
agreement to the orbital spacings of the satellites of the Jovian planets and
to the planet spacings in the Solar System. For galaxies we derive the baryonic
Tully-Fisher relation and the MOND acceleration, so galaxy velocity curves are
explained without requiring 'dark matter'. For the universe, we derive a new
Hubble relation that accounts for the accelerated expansion with a matter
density at about 5% of the critical matter/energy density, with the remainder
being large-scale quantization zero-point energy. A possible laboratory test is
proposed.
| [
{
"created": "Fri, 28 Mar 2003 17:29:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Preston",
"Howard G.",
""
],
[
"Potter",
"Franklin",
""
]
] | We explore a theory of large-scale gravitational quantization, using the general relativistic Hamilton-Jacobi equation to create quantization conditions via a new scalar wave equation dependent upon the total mass and the total vector angular momentum only. Instead of h-bar, a local invariant quantity proportional to the total angular momentum dictates the quantization conditions. In the Schwarzschild metric the theory predicts eigenstates with quantized energy per mass and angular momentum per mass. We find excellent agreement to the orbital spacings of the satellites of the Jovian planets and to the planet spacings in the Solar System. For galaxies we derive the baryonic Tully-Fisher relation and the MOND acceleration, so galaxy velocity curves are explained without requiring 'dark matter'. For the universe, we derive a new Hubble relation that accounts for the accelerated expansion with a matter density at about 5% of the critical matter/energy density, with the remainder being large-scale quantization zero-point energy. A possible laboratory test is proposed. |
2401.16259 | David Kubiznak | Tomas Hale, David Kubiznak, Jana Men\v{s}\'ikov\'a | Optical properties of black holes in regularized Maxwell theory | 21 pages, 22 figures | null | null | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Regularized Maxwell electrodynamics is a recently discovered theory of
non-linear electrodynamics, with a "minimally regularized" field strength of a
point charge, that is "very close" to the Maxwell theory in many aspects. In
this paper we investigate some of the optical properties of its black holes.
Namely, we study geodesics, gravitational red-shift, black hole shadow, as well
as investigate the relationship between the behavior of (null geodesic)
Lyapunov exponents and the existence of thermodynamic critical points in both
canonical and grand-canonical ensembles.
| [
{
"created": "Mon, 29 Jan 2024 16:09:45 GMT",
"version": "v1"
}
] | 2024-01-30 | [
[
"Hale",
"Tomas",
""
],
[
"Kubiznak",
"David",
""
],
[
"Menšíková",
"Jana",
""
]
] | Regularized Maxwell electrodynamics is a recently discovered theory of non-linear electrodynamics, with a "minimally regularized" field strength of a point charge, that is "very close" to the Maxwell theory in many aspects. In this paper we investigate some of the optical properties of its black holes. Namely, we study geodesics, gravitational red-shift, black hole shadow, as well as investigate the relationship between the behavior of (null geodesic) Lyapunov exponents and the existence of thermodynamic critical points in both canonical and grand-canonical ensembles. |
gr-qc/0402100 | Euro Spallucci | E.I.Guendelman, E. Spallucci | Conformally Invariant Brane-universe and the Cosmological Constant | 2 pages; Revtex; contribution to the Proceedings of the 10th Marcel
Grossman Meeting | null | 10.1142/9789812704030_0134 | null | gr-qc hep-th | null | A relativistic 3-brane can be given a conformally invariant, gauge-type,
formulation provided the embedding space is six-dimensional. The implementation
of conformal invariance requires the use of a modified measure, independent of
the metric in the action. A brane-world scenario without the need of a
cosmological constant in 6D can be constructed. Thus, no ``old'' cosmological
constant problem appears at this level.
| [
{
"created": "Tue, 24 Feb 2004 12:12:21 GMT",
"version": "v1"
}
] | 2016-11-09 | [
[
"Guendelman",
"E. I.",
""
],
[
"Spallucci",
"E.",
""
]
] | A relativistic 3-brane can be given a conformally invariant, gauge-type, formulation provided the embedding space is six-dimensional. The implementation of conformal invariance requires the use of a modified measure, independent of the metric in the action. A brane-world scenario without the need of a cosmological constant in 6D can be constructed. Thus, no ``old'' cosmological constant problem appears at this level. |
0906.4767 | Martin Bojowald | Martin Bojowald, Juan D. Reyes, Rakesh Tibrewala | Non-marginal LTB-like models with inverse triad corrections from loop
quantum gravity | 35 pages, 1 figure | Phys.Rev.D80:084002,2009 | 10.1103/PhysRevD.80.084002 | IGC-09/6-4 | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Marginal LTB models with corrections from loop quantum gravity have recently
been studied with an emphasis on potential singularity resolution. This paper
corroborates and extends the analysis in two regards: (i) the whole class of
LTB models, including non-marginal ones, is considered, and (ii) an alternative
procedure to derive anomaly-free models is presented which first implements
anomaly-freedom in spherical symmetry and then the LTB conditions rather than
the other way around. While the two methods give slightly different equations
of motion, not altogether surprisingly given the ubiquitous sprawl of
quantization ambiguities, final conclusions remain unchanged: Compared to
quantizations of homogeneous models, bounces seem to appear less easily in
inhomogeneous situations, and even the existence of homogeneous solutions as
special cases in inhomogeneous models may be precluded by quantum effects.
However, compared to marginal models, bouncing solutions seem more likely with
non-marginal models.
| [
{
"created": "Thu, 25 Jun 2009 18:30:46 GMT",
"version": "v1"
}
] | 2009-11-06 | [
[
"Bojowald",
"Martin",
""
],
[
"Reyes",
"Juan D.",
""
],
[
"Tibrewala",
"Rakesh",
""
]
] | Marginal LTB models with corrections from loop quantum gravity have recently been studied with an emphasis on potential singularity resolution. This paper corroborates and extends the analysis in two regards: (i) the whole class of LTB models, including non-marginal ones, is considered, and (ii) an alternative procedure to derive anomaly-free models is presented which first implements anomaly-freedom in spherical symmetry and then the LTB conditions rather than the other way around. While the two methods give slightly different equations of motion, not altogether surprisingly given the ubiquitous sprawl of quantization ambiguities, final conclusions remain unchanged: Compared to quantizations of homogeneous models, bounces seem to appear less easily in inhomogeneous situations, and even the existence of homogeneous solutions as special cases in inhomogeneous models may be precluded by quantum effects. However, compared to marginal models, bouncing solutions seem more likely with non-marginal models. |
gr-qc/0605056 | Juan A. Valiente-Kroon | JA Valiente Kroon | On smoothness-asymmetric null infinities | 13 pages, 1 figure | Class.Quant.Grav. 23 (2006) 3593-3606 | 10.1088/0264-9381/23/10/022 | null | gr-qc | null | We discuss the existence of asymptotically Euclidean initial data sets to the
vacuum Einstein field equations which would give rise (modulo an existence
result for the evolution equations near spatial infinity) to developments with
a past and a future null infinity of different smoothness. For simplicity, the
analysis is restricted to the class of conformally flat, axially symmetric
initial data sets. It is shown how the free parameters in the second
fundamental form of the data can be used to satisfy certain obstructions to the
smoothness of null infinity. The resulting initial data sets could be
interpreted as those of some sort of (non-linearly) distorted Schwarzschild
black hole. Its developments would be so that they admit a peeling future null
infinity, but at the same time have a polyhomogeneous (non-peeling) past null
infinity.
| [
{
"created": "Wed, 10 May 2006 09:15:27 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Kroon",
"JA Valiente",
""
]
] | We discuss the existence of asymptotically Euclidean initial data sets to the vacuum Einstein field equations which would give rise (modulo an existence result for the evolution equations near spatial infinity) to developments with a past and a future null infinity of different smoothness. For simplicity, the analysis is restricted to the class of conformally flat, axially symmetric initial data sets. It is shown how the free parameters in the second fundamental form of the data can be used to satisfy certain obstructions to the smoothness of null infinity. The resulting initial data sets could be interpreted as those of some sort of (non-linearly) distorted Schwarzschild black hole. Its developments would be so that they admit a peeling future null infinity, but at the same time have a polyhomogeneous (non-peeling) past null infinity. |
1105.1087 | Ujjal Debnath | Writambhara Chakraborty | Accelerating Expansion of the Universe | Ph.D Thesis (2010), 157 pages, 57 figures | null | null | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This thesis concentrates on the accelerated expansion of the Universe
recently explored by measurements of redshift and luminosity-distance relations
of type Ia Supernovae. We have considered a model of the universe filled with
modified Chaplygin gas and barotropic fluid. The role of dynamical cosmological
constant has been explored with Modified Chaplygin Gas as the background fluid.
Various phenomenological models for \Lambda have been studied in presence of
the gravitational constant G to be constant or time dependent. A new form of
the well known Chaplygin gas model has been presented by introducing
inhomogeneity in the EOS. This model explains w=-1 crossing. An interaction of
this model with the scalar field has also been investigated through a
phenomenological coupling function. Tachyonic field has been depicted as dark
energy model to represent the present acceleration of the Universe. A mixture
of the tachyonic fluid has been considered with Generalized Chaplygin Gas to
show the role of the later as a dark energy candidate in presence of tachyonic
matter. A model of interaction has been studied with scalar field and the
inhomogeneous ideal fluid. Two forms of the ideal fluid have been analysed. A
power law expansion for the scale factor has been assumed to solve the
equations for the energy densities. Brans-Dicke theory has been used to
investigate the possibility of obtaining cosmic acceleration. For this purpose
a constant and a variable \omega (Brans-Dicke parameter) have been considered.
A self-interacting potential has been introduced to show its role in the
evolution of the Universe. This model has been studied in presence of
barotropic fluid and Generalized Chaplygin Gas.
| [
{
"created": "Wed, 4 May 2011 07:21:08 GMT",
"version": "v1"
}
] | 2011-05-06 | [
[
"Chakraborty",
"Writambhara",
""
]
] | This thesis concentrates on the accelerated expansion of the Universe recently explored by measurements of redshift and luminosity-distance relations of type Ia Supernovae. We have considered a model of the universe filled with modified Chaplygin gas and barotropic fluid. The role of dynamical cosmological constant has been explored with Modified Chaplygin Gas as the background fluid. Various phenomenological models for \Lambda have been studied in presence of the gravitational constant G to be constant or time dependent. A new form of the well known Chaplygin gas model has been presented by introducing inhomogeneity in the EOS. This model explains w=-1 crossing. An interaction of this model with the scalar field has also been investigated through a phenomenological coupling function. Tachyonic field has been depicted as dark energy model to represent the present acceleration of the Universe. A mixture of the tachyonic fluid has been considered with Generalized Chaplygin Gas to show the role of the later as a dark energy candidate in presence of tachyonic matter. A model of interaction has been studied with scalar field and the inhomogeneous ideal fluid. Two forms of the ideal fluid have been analysed. A power law expansion for the scale factor has been assumed to solve the equations for the energy densities. Brans-Dicke theory has been used to investigate the possibility of obtaining cosmic acceleration. For this purpose a constant and a variable \omega (Brans-Dicke parameter) have been considered. A self-interacting potential has been introduced to show its role in the evolution of the Universe. This model has been studied in presence of barotropic fluid and Generalized Chaplygin Gas. |
2311.08033 | Pankaj Saini | Pankaj Saini, Sajad A. Bhat, Marc Favata, K. G. Arun | Eccentricity-induced systematic error on parametrized tests of general
relativity: Hierarchical Bayesian inference applied to a binary black hole
population | 24 pages, 9 figures, 1 table, published in Phys. Rev. D. v2: minor
changes to match the published version | Phys. Rev. D 109, 084056 (2024) | 10.1103/PhysRevD.109.084056 | LIGO Preprint No. P2300370 | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | One approach to testing general relativity (GR) introduces free parameters in
the post-Newtonian (PN) expansion of the gravitational-wave (GW) phase. If
systematic errors on these testing GR (TGR) parameters exceed the statistical
errors, this may signal a false violation of GR. Here, we consider systematic
errors produced by unmodeled binary eccentricity. Since the eccentricity of GW
events in ground-based detectors is expected to be small or negligible, the use
of quasicircular waveform models for testing GR may be safe when analyzing a
small number of events. However, as the catalog size of GW detections
increases, more stringent bounds on GR deviations can be placed by combining
information from multiple events. In that case, even small systematic biases
may become significant. We apply the approach of hierarchical Bayesian
inference to model the posterior probability distributions of the TGR
parameters inferred from a population of eccentric binary black holes (BBHs).
We assume each TGR parameter value varies across the BBH population according
to a Gaussian distribution. We compute the posterior distributions for these
Gaussian hyperparameters. This is done for LIGO and Cosmic Explorer (CE). We
find that systematic biases from unmodeled eccentricity can signal false GR
violations for both detectors when considering constraints set by a catalog of
events. We also compute the projected bounds on the $10$ TGR parameters when
eccentricity is included as a parameter in the waveform model. We find that the
first four dimensionless TGR deformation parameters can be bounded at $90\%$
confidence to $\delta \hat{\varphi}_i \lesssim 10^{-2}$ for LIGO and $\lesssim
10^{-3}$ for CE [where $i=(0,1,2,3)$]. In comparison to the circular orbit
case, the combined bounds on the TGR parameters worsen by a modest factor of
$\lesssim 2$ when eccentricity is included in the waveform.
| [
{
"created": "Tue, 14 Nov 2023 09:53:01 GMT",
"version": "v1"
},
{
"created": "Sat, 11 May 2024 08:48:39 GMT",
"version": "v2"
}
] | 2024-05-14 | [
[
"Saini",
"Pankaj",
""
],
[
"Bhat",
"Sajad A.",
""
],
[
"Favata",
"Marc",
""
],
[
"Arun",
"K. G.",
""
]
] | One approach to testing general relativity (GR) introduces free parameters in the post-Newtonian (PN) expansion of the gravitational-wave (GW) phase. If systematic errors on these testing GR (TGR) parameters exceed the statistical errors, this may signal a false violation of GR. Here, we consider systematic errors produced by unmodeled binary eccentricity. Since the eccentricity of GW events in ground-based detectors is expected to be small or negligible, the use of quasicircular waveform models for testing GR may be safe when analyzing a small number of events. However, as the catalog size of GW detections increases, more stringent bounds on GR deviations can be placed by combining information from multiple events. In that case, even small systematic biases may become significant. We apply the approach of hierarchical Bayesian inference to model the posterior probability distributions of the TGR parameters inferred from a population of eccentric binary black holes (BBHs). We assume each TGR parameter value varies across the BBH population according to a Gaussian distribution. We compute the posterior distributions for these Gaussian hyperparameters. This is done for LIGO and Cosmic Explorer (CE). We find that systematic biases from unmodeled eccentricity can signal false GR violations for both detectors when considering constraints set by a catalog of events. We also compute the projected bounds on the $10$ TGR parameters when eccentricity is included as a parameter in the waveform model. We find that the first four dimensionless TGR deformation parameters can be bounded at $90\%$ confidence to $\delta \hat{\varphi}_i \lesssim 10^{-2}$ for LIGO and $\lesssim 10^{-3}$ for CE [where $i=(0,1,2,3)$]. In comparison to the circular orbit case, the combined bounds on the TGR parameters worsen by a modest factor of $\lesssim 2$ when eccentricity is included in the waveform. |
1803.01105 | Fabio Briscese | Fabio Briscese, Francesco Calogero | Isochronous solutions of Einstein's equations and their Newtonian limit | arXiv admin note: text overlap with arXiv:1406.7156 | Int. J. of Geom. Meth. in Mod. Phys. Vol. 15 (2018) 1850101 | 10.1142/S0219887818501013 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been recently demonstrated that it is possible to construct
isochronous cosmologies, extending to general relativity a result valid for
non-relativistic Hamiltonian systems. In this paper we review these findings
and we discuss the Newtonian limit of these isochronous spacetimes, showing
that it reproduces the analogous findings in the context of non-relativistic
dynamics.
| [
{
"created": "Sat, 3 Mar 2018 04:19:24 GMT",
"version": "v1"
}
] | 2018-03-06 | [
[
"Briscese",
"Fabio",
""
],
[
"Calogero",
"Francesco",
""
]
] | It has been recently demonstrated that it is possible to construct isochronous cosmologies, extending to general relativity a result valid for non-relativistic Hamiltonian systems. In this paper we review these findings and we discuss the Newtonian limit of these isochronous spacetimes, showing that it reproduces the analogous findings in the context of non-relativistic dynamics. |
0802.0618 | Massimiliano Rinaldi | Massimiliano Rinaldi | Superluminal dispersion relations and the Unruh effect | Final discussion expanded, references added. Version accepted for
publication in Phys Rev D | Phys.Rev.D77:124029,2008 | 10.1103/PhysRevD.77.124029 | null | gr-qc hep-th | null | In the context of quantum gravity phenomenology, we study the Unruh effect in
the presence of superluminal dispersion relations. In particular, we estimate
the response function and the probability rate for an accelerated detector
coupled to a massless scalar field, whose dispersion relation becomes
essentially quadratic beyond a threshold momentum $k_p$. By means of
perturbative analysis, we show that superluminal dispersion induces a
correction to the Planckian spectrum, which tends to vanish as $k_p$ increases.
| [
{
"created": "Tue, 5 Feb 2008 13:52:38 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Feb 2008 15:57:22 GMT",
"version": "v2"
},
{
"created": "Mon, 26 May 2008 16:11:42 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Rinaldi",
"Massimiliano",
""
]
] | In the context of quantum gravity phenomenology, we study the Unruh effect in the presence of superluminal dispersion relations. In particular, we estimate the response function and the probability rate for an accelerated detector coupled to a massless scalar field, whose dispersion relation becomes essentially quadratic beyond a threshold momentum $k_p$. By means of perturbative analysis, we show that superluminal dispersion induces a correction to the Planckian spectrum, which tends to vanish as $k_p$ increases. |
1106.4984 | Richard Woodard | Cedric Deffayet, Gilles Esposito-Farese and Richard P. Woodard | Nonlocal metric formulations of MOND with sufficient lensing | 18 pages, uses Revtex4, revised for publication | Phys.Rev.D84:124054,2011 | 10.1103/PhysRevD.84.124054 | UFIFT-QG-11-02 | gr-qc astro-ph.GA hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate how to construct purely metric modifications of gravity which
agree with general relativity in the weak field regime appropriate to the solar
system, but which possess an ultra-weak field regime when the gravitational
acceleration becomes comparable to $a_0 \sim 10^{-10} {\rm m/s}^2$. In this
ultra-weak field regime, the models reproduce the MOND force without dark
matter and also give enough gravitational lensing to be consistent with
existing data. Our models are nonlocal and might conceivably derive from
quantum corrections to the effective field equations.
| [
{
"created": "Fri, 24 Jun 2011 14:50:16 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Dec 2011 01:43:27 GMT",
"version": "v2"
}
] | 2011-12-30 | [
[
"Deffayet",
"Cedric",
""
],
[
"Esposito-Farese",
"Gilles",
""
],
[
"Woodard",
"Richard P.",
""
]
] | We demonstrate how to construct purely metric modifications of gravity which agree with general relativity in the weak field regime appropriate to the solar system, but which possess an ultra-weak field regime when the gravitational acceleration becomes comparable to $a_0 \sim 10^{-10} {\rm m/s}^2$. In this ultra-weak field regime, the models reproduce the MOND force without dark matter and also give enough gravitational lensing to be consistent with existing data. Our models are nonlocal and might conceivably derive from quantum corrections to the effective field equations. |
0808.3246 | Gustav Holzegel | G. Holzegel | Stability and decay-rates for the five-dimensional Schwarzschild metric
under biaxial perturbations | null | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we prove the non-linear asymptotic stability of the
five-dimensional Schwarzschild metric under biaxial vacuum perturbations. This
is the statement that the evolution of (SU(2) x U(1))-symmetric vacuum
perturbations of initial data for the five-dimensional Schwarzschild metric
finally converges in a suitable sense to a member of the Schwarzschild family.
It constitutes the first result proving the existence of non-stationary vacuum
black holes arising from asymptotically flat initial data dynamically
approaching a stationary solution. In fact, we show quantitative rates of
approach. The proof relies on vectorfield multiplier estimates, which are used
in conjunction with a bootstrap argument to establish polynomial decay rates
for the radiation on the perturbed spacetime. Despite being applied here in a
five-dimensional context, the techniques are quite robust and may admit
applications to various four-dimensional stability problems.
| [
{
"created": "Sun, 24 Aug 2008 13:29:27 GMT",
"version": "v1"
}
] | 2008-08-26 | [
[
"Holzegel",
"G.",
""
]
] | In this paper we prove the non-linear asymptotic stability of the five-dimensional Schwarzschild metric under biaxial vacuum perturbations. This is the statement that the evolution of (SU(2) x U(1))-symmetric vacuum perturbations of initial data for the five-dimensional Schwarzschild metric finally converges in a suitable sense to a member of the Schwarzschild family. It constitutes the first result proving the existence of non-stationary vacuum black holes arising from asymptotically flat initial data dynamically approaching a stationary solution. In fact, we show quantitative rates of approach. The proof relies on vectorfield multiplier estimates, which are used in conjunction with a bootstrap argument to establish polynomial decay rates for the radiation on the perturbed spacetime. Despite being applied here in a five-dimensional context, the techniques are quite robust and may admit applications to various four-dimensional stability problems. |
1306.4750 | Lorenzo Sebastiani | R. Di Criscienzo, R. Myrzakulov and L. Sebastiani | Looking for empty topological wormhole spacetimes in $F(R)$-modified
gravity | 13 pages, published version | Classical and Quantum Gravity, v. 30, N23, 235013 (2013) | 10.1088/0264-9381/30/23/235013 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Much attention has been recently devoted to modified theories of gravity in
the attempt to efficiently describe both early inflation and late-time
acceleration of our universe without referring to the cosmological constant or
other ad hoc kinds of fluids. The simplest models overcome General Relativity
simply by replacing $R$ with $F(R)$ in the Einstein--Hilbert action.
Unfortunately, such models typically lack most of the beautiful solutions
discovered in Einstein's gravity. Nonetheless, in $F(R)$ gravity, it has been
possible to get at least few black holes, but still we do not know any empty
wormhole-like spacetime solution. The present paper aims to explain why it is
so hard to get such solutions (given that they exist). Few solutions are
derived in the simplest cases while only an implicit form has been obtained in
the non-trivial case.
| [
{
"created": "Thu, 20 Jun 2013 04:03:38 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Oct 2013 05:17:11 GMT",
"version": "v2"
}
] | 2015-06-16 | [
[
"Di Criscienzo",
"R.",
""
],
[
"Myrzakulov",
"R.",
""
],
[
"Sebastiani",
"L.",
""
]
] | Much attention has been recently devoted to modified theories of gravity in the attempt to efficiently describe both early inflation and late-time acceleration of our universe without referring to the cosmological constant or other ad hoc kinds of fluids. The simplest models overcome General Relativity simply by replacing $R$ with $F(R)$ in the Einstein--Hilbert action. Unfortunately, such models typically lack most of the beautiful solutions discovered in Einstein's gravity. Nonetheless, in $F(R)$ gravity, it has been possible to get at least few black holes, but still we do not know any empty wormhole-like spacetime solution. The present paper aims to explain why it is so hard to get such solutions (given that they exist). Few solutions are derived in the simplest cases while only an implicit form has been obtained in the non-trivial case. |
1105.3245 | Alberto Carrasco Ferreira | Alberto Carrasco, Marc Mars | Uniqueness theorems for static spacetimes containing marginally outer
trapped surfaces | 30 pages, 9 figures | null | 10.1088/0264-9381/28/17/175018 | null | gr-qc math.DG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Marginally outer trapped surfaces are widely considered as the best
quasi-local replacements for event horizons of black holes in General
Relativity. However, this equivalence is far from being proved, even in
stationary and static situations. In this paper we study an important aspect of
this equivalence, namely whether classic uniqueness theorems of static black
holes can be extended to static spacetimes containing weakly outer trapped
surfaces or not. Our main theorem states that, under reasonable hypotheses, a
static spacetime satisfying the null energy condition and containing an
asymptotically flat initial data set, possibly with boundary, which possesses a
bounding weakly outer trapped surface is a unique spacetime. A related result
to this theorem was given in arXiv:0711.1299, where we proved that no bounding
weakly outer trapped surface can penetrate into the exterior region of the
initial data where the static Killing vector is timelike. In this paper, we
also fill some gaps in arXiv:0711.1299 and extend this confinement result to
initial data sets with boundary.
| [
{
"created": "Mon, 16 May 2011 23:31:43 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Carrasco",
"Alberto",
""
],
[
"Mars",
"Marc",
""
]
] | Marginally outer trapped surfaces are widely considered as the best quasi-local replacements for event horizons of black holes in General Relativity. However, this equivalence is far from being proved, even in stationary and static situations. In this paper we study an important aspect of this equivalence, namely whether classic uniqueness theorems of static black holes can be extended to static spacetimes containing weakly outer trapped surfaces or not. Our main theorem states that, under reasonable hypotheses, a static spacetime satisfying the null energy condition and containing an asymptotically flat initial data set, possibly with boundary, which possesses a bounding weakly outer trapped surface is a unique spacetime. A related result to this theorem was given in arXiv:0711.1299, where we proved that no bounding weakly outer trapped surface can penetrate into the exterior region of the initial data where the static Killing vector is timelike. In this paper, we also fill some gaps in arXiv:0711.1299 and extend this confinement result to initial data sets with boundary. |
1512.02247 | Aaron Zimmerman | Aaron Zimmerman and Zachary Mark | Damped and zero-damped quasinormal modes of charged, nearly extremal
black holes | 24 pages, 11 figures, typos corrected and footnotes removed to
reflect published version and errata | Phys. Rev. D 93, 044033 (2016), Phys. Rev. D 93, 089905(E) (2016) | 10.1103/PhysRevD.93.044033, 10.1103/PhysRevD.93.089905 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Despite recent progress, the complete understanding of the perturbations of
charged, rotating black holes as described by the Kerr-Newman metric remains an
open and fundamental problem in relativity. In this study, we explore the
existence of families of quasinormal modes of Kerr-Newman black holes whose
decay rates limit to zero at extremality, called zero-damped modes in past
studies. We review the nearly extremal and WKB approximation methods for
spin-weighted scalar fields (governed by the Dudley-Finley equation) and give
an accounting of the regimes where scalar zero-damped and damped modes exist.
Using Leaver's continued fraction method, we verify that these approximations
give accurate predictions for the frequencies in their regimes of validity. In
the nonrotating limit, we argue that gravito-electromagnetic perturbations of
nearly extremal Reissner-Nordstr\"{o}m black holes have zero-damped modes in
addition to the well-known spectrum of damped modes. We provide an analytic
formula for the frequencies of these modes, verify their existence using a
numerical search, and demonstrate the accuracy of our formula. These results,
along with recent numerical studies, point to the existence of a simple
universal equation for the frequencies of zero-damped gravito-electromagnetic
modes of Kerr-Newman black holes, whose precise form remains an open question.
| [
{
"created": "Mon, 7 Dec 2015 21:13:01 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Apr 2016 15:29:41 GMT",
"version": "v2"
}
] | 2016-04-14 | [
[
"Zimmerman",
"Aaron",
""
],
[
"Mark",
"Zachary",
""
]
] | Despite recent progress, the complete understanding of the perturbations of charged, rotating black holes as described by the Kerr-Newman metric remains an open and fundamental problem in relativity. In this study, we explore the existence of families of quasinormal modes of Kerr-Newman black holes whose decay rates limit to zero at extremality, called zero-damped modes in past studies. We review the nearly extremal and WKB approximation methods for spin-weighted scalar fields (governed by the Dudley-Finley equation) and give an accounting of the regimes where scalar zero-damped and damped modes exist. Using Leaver's continued fraction method, we verify that these approximations give accurate predictions for the frequencies in their regimes of validity. In the nonrotating limit, we argue that gravito-electromagnetic perturbations of nearly extremal Reissner-Nordstr\"{o}m black holes have zero-damped modes in addition to the well-known spectrum of damped modes. We provide an analytic formula for the frequencies of these modes, verify their existence using a numerical search, and demonstrate the accuracy of our formula. These results, along with recent numerical studies, point to the existence of a simple universal equation for the frequencies of zero-damped gravito-electromagnetic modes of Kerr-Newman black holes, whose precise form remains an open question. |
gr-qc/0403032 | Mihalis Dafermos | Mihalis Dafermos | Spherically symmetric spacetimes with a trapped surface | 14 pages, 8 figures, revised | Class.Quant.Grav. 22 (2005) 2221-2232 | 10.1088/0264-9381/22/11/019 | null | gr-qc | null | This paper investigates the global properties of a class of spherically
symmetric spacetimes. The class contains the maximal development of
asymptotically flat spherically symmetric initial data for a wide variety of
coupled Einstein-matter systems. For this class, it is proven here that the
existence of a single trapped surface or marginally trapped surface implies the
completeness of future null infinity and the formation of an event horizon
whose area radius is bounded by twice the final Bondi mass.
| [
{
"created": "Mon, 8 Mar 2004 16:22:30 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Nov 2004 15:27:26 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Dafermos",
"Mihalis",
""
]
] | This paper investigates the global properties of a class of spherically symmetric spacetimes. The class contains the maximal development of asymptotically flat spherically symmetric initial data for a wide variety of coupled Einstein-matter systems. For this class, it is proven here that the existence of a single trapped surface or marginally trapped surface implies the completeness of future null infinity and the formation of an event horizon whose area radius is bounded by twice the final Bondi mass. |
1309.0091 | Olivier Minazzoli | Olivier Minazzoli | The \gamma\ parameter in Brans-Dicke-like (light-)Scalar-Tensor theory
with a universal scalar/matter coupling | 6 pages, accepted in Phys. Rev. D. arXiv admin note: substantial text
overlap with arXiv:1208.2372 | Phys. Rev. D 88, 064050 (2013) | 10.1103/PhysRevD.88.064050 | null | gr-qc hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The post-Newtonian parameter \gamma\ resulting from a universal scalar/matter
coupling is investigated in Brans-Dicke-like Scalar-Tensor theories where the
scalar potential is assumed to be negligible. Conversely to previous studies,
we use a perfect fluid formalism in order to get the explicit scalar-field
equation. It is shown that the metric can be put in its standard post-Newtonian
form. However, it is pointed out that 1-\gamma\ could be either positive, null
or negative for finite value of \omega_0, depending on the coupling function;
while Scalar-Tensor theories without coupling always predict \gamma<1 for
finite value of \omega_0.
| [
{
"created": "Sat, 31 Aug 2013 10:21:22 GMT",
"version": "v1"
}
] | 2013-09-26 | [
[
"Minazzoli",
"Olivier",
""
]
] | The post-Newtonian parameter \gamma\ resulting from a universal scalar/matter coupling is investigated in Brans-Dicke-like Scalar-Tensor theories where the scalar potential is assumed to be negligible. Conversely to previous studies, we use a perfect fluid formalism in order to get the explicit scalar-field equation. It is shown that the metric can be put in its standard post-Newtonian form. However, it is pointed out that 1-\gamma\ could be either positive, null or negative for finite value of \omega_0, depending on the coupling function; while Scalar-Tensor theories without coupling always predict \gamma<1 for finite value of \omega_0. |
gr-qc/9907003 | Gelu Belinchon | J. A. Belinchon | Cosmological models with variable constants | 15 pages. submitted to IJTP | Int.J.Theor.Phys.39:1669-1686,2000 | 10.1023/A:1003644614145 | null | gr-qc | null | The behavior of the constants, G,c,h,a,e,m and Lambda, considering them as
variable, in the framework of a flat cosmological model with FRW symmetries
described by a bulk viscous fluid and considering mechanisms of adiabatic
matter creation are investigated. Within two models; one with radiation
predominance and another of matter predominance, this behavior are studied.
| [
{
"created": "Thu, 1 Jul 1999 22:51:16 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Oct 1999 17:29:08 GMT",
"version": "v2"
},
{
"created": "Fri, 19 Nov 1999 21:09:34 GMT",
"version": "v3"
}
] | 2014-11-17 | [
[
"Belinchon",
"J. A.",
""
]
] | The behavior of the constants, G,c,h,a,e,m and Lambda, considering them as variable, in the framework of a flat cosmological model with FRW symmetries described by a bulk viscous fluid and considering mechanisms of adiabatic matter creation are investigated. Within two models; one with radiation predominance and another of matter predominance, this behavior are studied. |
1501.06960 | Changjun Gao | Changjun Gao and You-Gen Shen | Cosmic evolution of scalar fields with multiple vacua: generalized DBI
and quintessence | 8 pages, 9 figures, accepted by IJTP. A number of typos corrected | Int. J. Theor. Phys (2016) 55: 4532 | 10.1007/s10773-016-3076-x | null | gr-qc astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We find a method to rewrite the equations of motion of scalar fields,
generalized DBI field and quintessence, in the autonomous form
for\emph{arbitrary} scalar potentials. With the aid of this method, we explore
the cosmic evolution of generalized DBI field and quintessence with the
potential of multiple vacua. Then we find that the scalars are always frozen in
the false or true vacuum in the end. Compared to the evolution of quintessence,
the generalized DBI field has more times of oscillations around the vacuum of
the potential. The reason for this point is that, with the increasing of speed
$\dot{\phi}$, the friction term of generalized DBI field is greatly decreased.
Thus the generalized DBI field acquires more times of oscillations.
| [
{
"created": "Wed, 28 Jan 2015 00:46:29 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Jan 2015 07:42:03 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Feb 2015 00:26:51 GMT",
"version": "v3"
},
{
"created": "Thu, 26 Feb 2015 05:17:50 GMT",
"version": "v4"
},
{
"created": "Wed, 8 Jun 2016 14:18:45 GMT",
"version": "v5"
}
] | 2016-09-19 | [
[
"Gao",
"Changjun",
""
],
[
"Shen",
"You-Gen",
""
]
] | We find a method to rewrite the equations of motion of scalar fields, generalized DBI field and quintessence, in the autonomous form for\emph{arbitrary} scalar potentials. With the aid of this method, we explore the cosmic evolution of generalized DBI field and quintessence with the potential of multiple vacua. Then we find that the scalars are always frozen in the false or true vacuum in the end. Compared to the evolution of quintessence, the generalized DBI field has more times of oscillations around the vacuum of the potential. The reason for this point is that, with the increasing of speed $\dot{\phi}$, the friction term of generalized DBI field is greatly decreased. Thus the generalized DBI field acquires more times of oscillations. |
1007.3365 | Petr Tretyakov | M.Skugoreva, A.Toporensky and P.Tretyakov | Cosmological dynamics in six-order gravity | null | Grav.Cosmol.17:110-118,2011 | 10.1134/S0202289311020198 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider cosmological dynamics in generalized modified gravity theory with
the $R\Box R$ term added to the action of the form $R+R^N$. Influence of $R
\Box R$ term to the known solutions of modified gravity is described. We show
that in particular case of $N=3$ these two non-Einstein terms are equally
important on power-law solutions. These solutions and their stability have been
studied using dynamical system approach. Some results for the case of $N \ne 3$
(including stability of de Sitter solution in the theory under investigation)
have been found using other methods.
| [
{
"created": "Tue, 20 Jul 2010 08:55:07 GMT",
"version": "v1"
}
] | 2011-06-10 | [
[
"Skugoreva",
"M.",
""
],
[
"Toporensky",
"A.",
""
],
[
"Tretyakov",
"P.",
""
]
] | We consider cosmological dynamics in generalized modified gravity theory with the $R\Box R$ term added to the action of the form $R+R^N$. Influence of $R \Box R$ term to the known solutions of modified gravity is described. We show that in particular case of $N=3$ these two non-Einstein terms are equally important on power-law solutions. These solutions and their stability have been studied using dynamical system approach. Some results for the case of $N \ne 3$ (including stability of de Sitter solution in the theory under investigation) have been found using other methods. |
2303.09215 | Yuqian Zhao | Yuqian Zhao, Bing Sun, Kai Lin and Zhoujian Cao | The Axial Gravitational Ringing of a Spherically Symmetric Black Hole
Surrounded by Dark Matter Spike | 12 pages, 5 figures, 4 tables | Phys. Rev. D 108, 024070(2023) | 10.1103/PhysRevD.108.024070 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Supermassive black holes at the center of each galaxy may be surrounded by
dark matter. Such dark matter admits a spike structure and vanishes at a
certain distance from the black hole. This dark matter will impact the
spacetime near the black hole and the related ringing gravitational waves can
show distinguished features of the black hole without dark matter. In the
present work, we focus on the quasi-normal modes of the axial gravitational
perturbation who dominate the ringdown process of the perturbed black holes
surrounded by dark matter spikes. The relativistic modification results in less
impact on QNMs. And the relative ringing frequency difference between the black
holes with and without dark matter can be as large as $10^{-2}$. These features
can be used in future gravitational wave detection about extremal mass ratio
inspiral systems to probe the existence of dark matter around supermassive
black holes.
| [
{
"created": "Thu, 16 Mar 2023 10:44:22 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Mar 2023 12:41:06 GMT",
"version": "v2"
},
{
"created": "Tue, 1 Aug 2023 07:40:10 GMT",
"version": "v3"
}
] | 2023-08-02 | [
[
"Zhao",
"Yuqian",
""
],
[
"Sun",
"Bing",
""
],
[
"Lin",
"Kai",
""
],
[
"Cao",
"Zhoujian",
""
]
] | Supermassive black holes at the center of each galaxy may be surrounded by dark matter. Such dark matter admits a spike structure and vanishes at a certain distance from the black hole. This dark matter will impact the spacetime near the black hole and the related ringing gravitational waves can show distinguished features of the black hole without dark matter. In the present work, we focus on the quasi-normal modes of the axial gravitational perturbation who dominate the ringdown process of the perturbed black holes surrounded by dark matter spikes. The relativistic modification results in less impact on QNMs. And the relative ringing frequency difference between the black holes with and without dark matter can be as large as $10^{-2}$. These features can be used in future gravitational wave detection about extremal mass ratio inspiral systems to probe the existence of dark matter around supermassive black holes. |
gr-qc/0401115 | Lars Samuelsson | Max Karlovini and Lars Samuelsson | Elastic Stars in General Relativity: III. Stiff ultrarigid exact
solutions | 20 pages, 6 figures. Added remarks on our numerical method as well as
the relation to the Ernst equation | Class.Quant.Grav. 21 (2004) 4531-4548 | 10.1088/0264-9381/21/19/003 | USITP 2004-2 | gr-qc | null | We present an equation of state for elastic matter which allows for purely
longitudinal elastic waves in all propagation directions, not just principal
directions. The speed of these waves is equal to the speed of light whereas the
transversal type speeds are also very high, comparable to but always strictly
less than that of light. Clearly such an equation of state does not give a
reasonable matter description for the crust of a neutron star, but it does
provide a nice causal toy model for an extremely rigid phase in a neutron star
core, should such a phase exist. Another reason for focusing on this particular
equation of state is simply that it leads to a very simple recipe for finding
stationary rigid motion exact solutions to the Einstein equations. In fact, we
show that a very large class of stationary spacetimes with constant Ricci
scalar can be interpreted as rigid motion solutions with this matter source. We
use the recipe to derive a static spherically symmetric exact solution with
constant energy density, regular centre and finite radius, having a nontrivial
parameter that can be varied to yield a mass-radius curve from which stability
can be read off. It turns out that the solution is stable down to a tenuity R/M
slightly less than 3. The result of this static approach to stability is
confirmed by a numerical determination of the fundamental radial oscillation
mode frequency. We also present another solution with outwards decreasing
energy density. Unfortunately, this solution only has a trivial scaling
parameter and is found to be unstable.
| [
{
"created": "Wed, 28 Jan 2004 20:54:37 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Jan 2004 22:34:18 GMT",
"version": "v2"
},
{
"created": "Tue, 14 Sep 2004 11:12:56 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Karlovini",
"Max",
""
],
[
"Samuelsson",
"Lars",
""
]
] | We present an equation of state for elastic matter which allows for purely longitudinal elastic waves in all propagation directions, not just principal directions. The speed of these waves is equal to the speed of light whereas the transversal type speeds are also very high, comparable to but always strictly less than that of light. Clearly such an equation of state does not give a reasonable matter description for the crust of a neutron star, but it does provide a nice causal toy model for an extremely rigid phase in a neutron star core, should such a phase exist. Another reason for focusing on this particular equation of state is simply that it leads to a very simple recipe for finding stationary rigid motion exact solutions to the Einstein equations. In fact, we show that a very large class of stationary spacetimes with constant Ricci scalar can be interpreted as rigid motion solutions with this matter source. We use the recipe to derive a static spherically symmetric exact solution with constant energy density, regular centre and finite radius, having a nontrivial parameter that can be varied to yield a mass-radius curve from which stability can be read off. It turns out that the solution is stable down to a tenuity R/M slightly less than 3. The result of this static approach to stability is confirmed by a numerical determination of the fundamental radial oscillation mode frequency. We also present another solution with outwards decreasing energy density. Unfortunately, this solution only has a trivial scaling parameter and is found to be unstable. |
1602.02663 | Artur Alho | Artur Alho and Simone Calogero | A stellar model with diffusion in general relativity | 16 pages, 2 figures. v2: 17 pages, matches final published version | null | 10.1016/j.geomphys.2017.05.018 | null | gr-qc math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a spherically symmetric stellar model in general relativity whose
interior consists of a pressureless fluid undergoing microscopic velocity
diffusion in a cosmological scalar field. We show that the diffusion dynamics
compel the interior to be spatially homogeneous, by which one can infer
immediately that within our model, and in contrast to the diffusion-free case,
no naked singularities can form in the gravitational collapse. We then study
the problem of matching an exterior Bondi type metric to the surface of the
star and find that the exterior can be chosen to be a modified Vaidya metric
with variable cosmological constant. Finally, we study in detail the causal
structure of an explicit, self-similar solution.
| [
{
"created": "Mon, 8 Feb 2016 17:42:56 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Jun 2017 13:19:56 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Alho",
"Artur",
""
],
[
"Calogero",
"Simone",
""
]
] | We consider a spherically symmetric stellar model in general relativity whose interior consists of a pressureless fluid undergoing microscopic velocity diffusion in a cosmological scalar field. We show that the diffusion dynamics compel the interior to be spatially homogeneous, by which one can infer immediately that within our model, and in contrast to the diffusion-free case, no naked singularities can form in the gravitational collapse. We then study the problem of matching an exterior Bondi type metric to the surface of the star and find that the exterior can be chosen to be a modified Vaidya metric with variable cosmological constant. Finally, we study in detail the causal structure of an explicit, self-similar solution. |
gr-qc/9905001 | Carey Carpenter Briggs | C. C. Briggs | Some General Expressions for the Coefficient of the 14th Chern Form | 11 pages | null | null | null | gr-qc | null | Some general expressions are given for the coefficient of the 14th Chern form
in terms of the Riemann-Christoffel curvature tensor and some of its
concomitants (e.g., Pontrjagin's characteristic tensors) for n-dimensional
differentiable manifolds having a general linear connection.
| [
{
"created": "Mon, 3 May 1999 02:55:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Briggs",
"C. C.",
""
]
] | Some general expressions are given for the coefficient of the 14th Chern form in terms of the Riemann-Christoffel curvature tensor and some of its concomitants (e.g., Pontrjagin's characteristic tensors) for n-dimensional differentiable manifolds having a general linear connection. |
0807.4221 | Lorenzo Iorio | Lorenzo Iorio | The impact of the oblateness of Regulus on the motion of its companion | LaTex, 6 pages, 5 figures, 1 table. Accepted by Astrophysics and
Space Science | Astrophys.SpaceSci.318:51-55,2008 | 10.1007/s10509-008-9889-1 | null | gr-qc astro-ph physics.space-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The fast spinning B-star Regulus has recently been found to be orbited by a
fainter companion in a close circular path with orbital period P_b = 40.11(2)
d. Being its equatorial radius R_e 32% larger than the polar one R_p, Regulus
possesses a remarkable quadrupole mass moment Q. We investigate the effects of
Q on the orbital period P_b of its companion in order to see if they are
measurable, given the present-day level of accuracy in measuring P_b.
Conversely, we will look for deviations from the third Kepler law, attributed
to the quadrupole mass moment Q of Regulus, to constrain the ratio \gamma=m/M
of the system's masses.
| [
{
"created": "Sat, 26 Jul 2008 07:22:27 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Aug 2008 19:30:28 GMT",
"version": "v2"
}
] | 2008-12-18 | [
[
"Iorio",
"Lorenzo",
""
]
] | The fast spinning B-star Regulus has recently been found to be orbited by a fainter companion in a close circular path with orbital period P_b = 40.11(2) d. Being its equatorial radius R_e 32% larger than the polar one R_p, Regulus possesses a remarkable quadrupole mass moment Q. We investigate the effects of Q on the orbital period P_b of its companion in order to see if they are measurable, given the present-day level of accuracy in measuring P_b. Conversely, we will look for deviations from the third Kepler law, attributed to the quadrupole mass moment Q of Regulus, to constrain the ratio \gamma=m/M of the system's masses. |
2102.10112 | Jose M. M. Senovilla | Jos\'e M M Senovilla | Hoyos negros y sus misteriosos interiores (Black holes and their
mysterious interiors) | 8 pages. Invited commentary on the 2020 physics Nobel prize by the
Revista Espa\~nola de F\'{\i}sica (Spanish Physics Magazine). In Spanish | Rev. Esp. Fisica, vol. 34, number 4, (2020) 41-48 | null | null | gr-qc math-ph math.MP physics.hist-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Singularity theorems constitute a major milestone of relativity. They
generated a panoply of fertile lines of research with dazzling physical
consequences.
(Los teoremas de singularidades constituyen uno de los mayores hitos de la
relatividad. Generaron una panoplia de f\'ertiles l\'ineas de investigaci\'on
con consecuencias f\'isicas deslumbrantes).
| [
{
"created": "Fri, 19 Feb 2021 16:10:55 GMT",
"version": "v1"
}
] | 2021-02-23 | [
[
"Senovilla",
"José M M",
""
]
] | Singularity theorems constitute a major milestone of relativity. They generated a panoply of fertile lines of research with dazzling physical consequences. (Los teoremas de singularidades constituyen uno de los mayores hitos de la relatividad. Generaron una panoplia de f\'ertiles l\'ineas de investigaci\'on con consecuencias f\'isicas deslumbrantes). |
2404.00715 | Orlando Luongo | Alessio Belfiglio, Orlando Luongo, Stefano Mancini, and Sebastiano
Tomasi | Entanglement entropy in quantum black holes | 15 pages, 7 figures | null | null | null | gr-qc hep-th quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the entanglement entropy for a massive Klein-Gordon field in two
Schwarzschild-like quantum black hole spacetimes, also including a nonminimal
coupling term with the background scalar curvature. To compute the entanglement
entropy, we start from the standard spherical shell discretisation procedure,
tracing over the degrees of freedom residing inside an imaginary surface. We
estimate the free parameters for such quantum metrics through a simple physical
argument based on Heisenberg uncertainty principle, along with alternative
proposals as asymptotic safety, trace anomaly, and graviton corpuscular
scaling. Our findings reveal a significant decrease in entropy compared to the
area law near the origin for the quantum metrics. In both scenarios, the
entanglement entropy converges to the expected area law sufficiently far from
the origin. We then compare these results to the entropy scaling in regular
Hayward and corrected-Hayward spacetimes to highlight the main differences with
such regular approaches.
| [
{
"created": "Sun, 31 Mar 2024 15:19:03 GMT",
"version": "v1"
}
] | 2024-04-02 | [
[
"Belfiglio",
"Alessio",
""
],
[
"Luongo",
"Orlando",
""
],
[
"Mancini",
"Stefano",
""
],
[
"Tomasi",
"Sebastiano",
""
]
] | We discuss the entanglement entropy for a massive Klein-Gordon field in two Schwarzschild-like quantum black hole spacetimes, also including a nonminimal coupling term with the background scalar curvature. To compute the entanglement entropy, we start from the standard spherical shell discretisation procedure, tracing over the degrees of freedom residing inside an imaginary surface. We estimate the free parameters for such quantum metrics through a simple physical argument based on Heisenberg uncertainty principle, along with alternative proposals as asymptotic safety, trace anomaly, and graviton corpuscular scaling. Our findings reveal a significant decrease in entropy compared to the area law near the origin for the quantum metrics. In both scenarios, the entanglement entropy converges to the expected area law sufficiently far from the origin. We then compare these results to the entropy scaling in regular Hayward and corrected-Hayward spacetimes to highlight the main differences with such regular approaches. |
gr-qc/9803035 | Carlos Barcelo Seron | C. Barcelo and L.J. Garay | Wormhole effective interactions in anti-de Sitter spacetime | 21 pages, LaTeX 2e, no figures | Int.J.Mod.Phys. D7 (1998) 623-645 | 10.1142/S0218271898000425 | null | gr-qc | null | The effects of asymptotically anti-de Sitter wormholes in low-energy field
theory are calculated in full detail for three different matter contents: a
conformal scalar field, an electromagnetic field and gravitons. There exists a
close relation between the choice of vacuum for the matter fields and the
selection of a basis of the Hilbert space of anti-de Sitter wormholes. In the
presence of conformal matter (i.e., conformal scalar or electromagnetic
fields), this relation allows us to interpret the elements of these bases as
wormhole states containing a given number of particles. This interpretation is
subject to the same kind of ambiguity in the definition of particle as that
arising from quantum field theory in curved spacetime. In the case of
gravitons, owing to the non-conformal coupling, it is not possible to describe
wormhole states in terms of their particle content.
| [
{
"created": "Tue, 10 Mar 1998 16:31:03 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Barcelo",
"C.",
""
],
[
"Garay",
"L. J.",
""
]
] | The effects of asymptotically anti-de Sitter wormholes in low-energy field theory are calculated in full detail for three different matter contents: a conformal scalar field, an electromagnetic field and gravitons. There exists a close relation between the choice of vacuum for the matter fields and the selection of a basis of the Hilbert space of anti-de Sitter wormholes. In the presence of conformal matter (i.e., conformal scalar or electromagnetic fields), this relation allows us to interpret the elements of these bases as wormhole states containing a given number of particles. This interpretation is subject to the same kind of ambiguity in the definition of particle as that arising from quantum field theory in curved spacetime. In the case of gravitons, owing to the non-conformal coupling, it is not possible to describe wormhole states in terms of their particle content. |
1305.2588 | Lisa Glaser | Fay Dowker and Lisa Glaser | Causal set d'Alembertians for various dimensions | 14 pages, 1 figure, published in Class. Quantum Grav (text and figure
were updated to agree with the published version) | 2013,Class. Quantum Grav. 30 195016 | 10.1088/0264-9381/30/19/195016 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose, for dimension d, a discrete Lorentz invariant operator on scalar
fields that approximates the Minkowski spacetime scalar d'Alembertian. For each
dimension, this gives rise to a scalar curvature estimator for causal sets, and
thence to a proposal for a causal set action.
| [
{
"created": "Sun, 12 May 2013 13:33:01 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Sep 2013 15:15:37 GMT",
"version": "v2"
}
] | 2013-09-13 | [
[
"Dowker",
"Fay",
""
],
[
"Glaser",
"Lisa",
""
]
] | We propose, for dimension d, a discrete Lorentz invariant operator on scalar fields that approximates the Minkowski spacetime scalar d'Alembertian. For each dimension, this gives rise to a scalar curvature estimator for causal sets, and thence to a proposal for a causal set action. |
gr-qc/0311041 | John Quiroga H. | Iver Brevik and John Quiroga Hurtado | Inflationary Dilatonic de Sitter Universe from Super Yang - Mills Theory
Perturbed by Scalars and Spinors | LaTeX, 12 pages | null | 10.1023/B:GERG.0000022579.16135.9b | null | gr-qc | null | In this paper a quantum N = 4 super Yang-Mills theory perturbed by
dilaton-coupled scalars and spinor fields is considered. The induced effective
action for such a theory is calculated on a dilaton-gravitational background
using the conformal anomaly found via the AdS/CFT correspondence. Considering
such an effective action (using the large N method) as a quantum correction to
the classical gravity action with cosmological constant, we study the effect
from the dilaton on the scale factor (this corresponds to an inflationary
universe without dilaton). It is shown that, depending on the initial
conditions for the dilaton, the dilaton may slow down or accelerate the
inflation process. At late times the dilaton is decaying exponentially.
Different possible cases corresponding to a dilatonic dS Universe are analyzed
with respect to the equations of motion.
| [
{
"created": "Thu, 13 Nov 2003 17:39:45 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Brevik",
"Iver",
""
],
[
"Hurtado",
"John Quiroga",
""
]
] | In this paper a quantum N = 4 super Yang-Mills theory perturbed by dilaton-coupled scalars and spinor fields is considered. The induced effective action for such a theory is calculated on a dilaton-gravitational background using the conformal anomaly found via the AdS/CFT correspondence. Considering such an effective action (using the large N method) as a quantum correction to the classical gravity action with cosmological constant, we study the effect from the dilaton on the scale factor (this corresponds to an inflationary universe without dilaton). It is shown that, depending on the initial conditions for the dilaton, the dilaton may slow down or accelerate the inflation process. At late times the dilaton is decaying exponentially. Different possible cases corresponding to a dilatonic dS Universe are analyzed with respect to the equations of motion. |
0709.1488 | Andreas Freise | S. Hild and A. Freise | A novel concept for increasing the peak sensitivity of LIGO by detuning
the arm cavities | 8 pages, 4 figures | Class.Quant.Grav.24:5453-5460,2007 | 10.1088/0264-9381/24/22/010 | null | gr-qc | null | We introduce a concept that uses detuned arm cavities to increase the shot
noise limited sensitivity of LIGO without increasing the light power inside the
arm cavities. Numerical simulations show an increased sensitivity between 125
and 400 Hz, with a maximal improvement of about 80% around 225 Hz, while the
sensitivity above 400Hz is decreased. Furthermore our concept is found to give
a sensitivity similar to that of a conventional RSE configuration with a
Signal-Recycling mirror of moderate reflectivity. In the near future detuned
arm cavities might be a beneficial alternative to RSE, due the potentially less
hardware intensive implementation of the proposed concept.
| [
{
"created": "Mon, 10 Sep 2007 21:10:59 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Hild",
"S.",
""
],
[
"Freise",
"A.",
""
]
] | We introduce a concept that uses detuned arm cavities to increase the shot noise limited sensitivity of LIGO without increasing the light power inside the arm cavities. Numerical simulations show an increased sensitivity between 125 and 400 Hz, with a maximal improvement of about 80% around 225 Hz, while the sensitivity above 400Hz is decreased. Furthermore our concept is found to give a sensitivity similar to that of a conventional RSE configuration with a Signal-Recycling mirror of moderate reflectivity. In the near future detuned arm cavities might be a beneficial alternative to RSE, due the potentially less hardware intensive implementation of the proposed concept. |
2309.10072 | Barak Shoshany | Barak Shoshany and Ben Snodgrass | Warp Drives and Closed Timelike Curves | 37 pages, 7 figures; corrected and substantially revised version | null | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is commonly accepted that superluminal travel may be used to facilitate
time travel. This is a purely special-relativistic argument, using the fact
that for observers in two frames of reference, separated by a spacelike
interval, the non-causal (spacelike) future of one observer includes part of
the causal past of the other. In this paper we provide a concrete realization
of this argument in a curved general-relativistic spacetime, using warp drives
as the means of faster-than-light travel. By generalizing the usual warp drive
metric to allow for a non-unit lapse function, we allow the warp drive to
switch between reference frames in a purely geometric way. With an additional
modification allowing the warp drive to have compact support, this permits us
to glue two warp drives together to construct a closed timelike geodesic, such
that a test particle following the geodesics of the two warp drives travels
back to its own past. This provides a precise mathematical model for the
connection between faster-than-light travel and time travel in general
relativity, and the first such model to be explicitly formulated using two warp
drives. We also give a detailed discussion of weak energy condition violations
in the non-unit-lapse warp drive.
| [
{
"created": "Mon, 18 Sep 2023 18:37:30 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Apr 2024 18:03:01 GMT",
"version": "v2"
}
] | 2024-04-24 | [
[
"Shoshany",
"Barak",
""
],
[
"Snodgrass",
"Ben",
""
]
] | It is commonly accepted that superluminal travel may be used to facilitate time travel. This is a purely special-relativistic argument, using the fact that for observers in two frames of reference, separated by a spacelike interval, the non-causal (spacelike) future of one observer includes part of the causal past of the other. In this paper we provide a concrete realization of this argument in a curved general-relativistic spacetime, using warp drives as the means of faster-than-light travel. By generalizing the usual warp drive metric to allow for a non-unit lapse function, we allow the warp drive to switch between reference frames in a purely geometric way. With an additional modification allowing the warp drive to have compact support, this permits us to glue two warp drives together to construct a closed timelike geodesic, such that a test particle following the geodesics of the two warp drives travels back to its own past. This provides a precise mathematical model for the connection between faster-than-light travel and time travel in general relativity, and the first such model to be explicitly formulated using two warp drives. We also give a detailed discussion of weak energy condition violations in the non-unit-lapse warp drive. |
gr-qc/9510015 | R. Beig, Univ. Wien. | R. Beig (Institut f\"ur Theoretische Physik, Universit\"at Wien) Piotr
T. Chrusciel (Departement de Mathematique, Faculte des Sciences, Tours) | Killing vectors in asymptotically flat space-times: I. Asymptotically
translational Killing vectors and the rigid positive energy theorem | 30 pages | J.Math.Phys. 37 (1996) 1939-1961 | 10.1063/1.531497 | null | gr-qc | null | We study Killing vector fields in asymptotically flat space-times. We prove
the following result, implicitly assumed in the uniqueness theory of stationary
black holes. If the conditions of the rigidity part of the positive energy
theorem are met, then in such space-times there are no asymptotically null
Killing vector fields except if the initial data set can be embedded in
Minkowski space-time. We also give a proof of the non-existence of non-singular
(in an appropriate sense) asymptotically flat space-times which satisfy an
energy condition and which have a null ADM four-momentum, under conditions
weaker than previously considered.
| [
{
"created": "Tue, 10 Oct 1995 10:28:54 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Dec 1995 12:38:57 GMT",
"version": "v2"
},
{
"created": "Thu, 17 Oct 1996 13:11:53 GMT",
"version": "v3"
}
] | 2016-08-31 | [
[
"Beig",
"R.",
"",
"Institut für Theoretische Physik, Universität Wien"
],
[
"Chrusciel",
"Piotr T.",
"",
"Departement de Mathematique, Faculte des Sciences, Tours"
]
] | We study Killing vector fields in asymptotically flat space-times. We prove the following result, implicitly assumed in the uniqueness theory of stationary black holes. If the conditions of the rigidity part of the positive energy theorem are met, then in such space-times there are no asymptotically null Killing vector fields except if the initial data set can be embedded in Minkowski space-time. We also give a proof of the non-existence of non-singular (in an appropriate sense) asymptotically flat space-times which satisfy an energy condition and which have a null ADM four-momentum, under conditions weaker than previously considered. |
1504.00072 | Yen-Kheng Lim | Gulmina Zaman Babar, Mubasher Jamil and Yen-Kheng Lim | Dynamics of a charged particle around a weakly magnetized naked
singularity | Added references, accepted for publication in Int.J.Mod.Phys.D | Int.J.Mod.Phys.D Vol. 25, No. 2 (2016) 1650024 | 10.1142/S0218271816500243 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the motion of a charged particle in the vicinity of a weakly
magnetized naked singularity. The escape velocity and energy of the particle
moving around the naked singularity after being kicked by another particle or
photon are investigated. Also at the innermost stable circular orbit (ISCO)
escape velocity and energy are examined. Effective potential and angular
momentum of the particle are also discussed. We discuss the center of mass
energy after collision between two particles having same mass and opposite
charges moving along the same circular orbit in the opposite direction. It is
investigated that under what conditions maximum energy can be produced as a
result of collision.
| [
{
"created": "Wed, 1 Apr 2015 00:36:48 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Apr 2015 05:52:37 GMT",
"version": "v2"
},
{
"created": "Mon, 28 Sep 2015 01:54:52 GMT",
"version": "v3"
},
{
"created": "Sat, 17 Oct 2015 02:08:24 GMT",
"version": "v4"
}
] | 2015-11-19 | [
[
"Babar",
"Gulmina Zaman",
""
],
[
"Jamil",
"Mubasher",
""
],
[
"Lim",
"Yen-Kheng",
""
]
] | We examine the motion of a charged particle in the vicinity of a weakly magnetized naked singularity. The escape velocity and energy of the particle moving around the naked singularity after being kicked by another particle or photon are investigated. Also at the innermost stable circular orbit (ISCO) escape velocity and energy are examined. Effective potential and angular momentum of the particle are also discussed. We discuss the center of mass energy after collision between two particles having same mass and opposite charges moving along the same circular orbit in the opposite direction. It is investigated that under what conditions maximum energy can be produced as a result of collision. |
1910.09267 | Sven Zschocke | Sven Zschocke | Post-linear metric of a compact source of matter | 32 pages, 2 figures | Physical Review D 100 (2019) 084005 | 10.1103/PhysRevD.100.084005 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Multipolar Post-Minkowskian (MPM) formalism represents an approach for
determining the metric density in the exterior of a compact source of matter.
In the MPM formalism the metric density is given in harmonic coordinates and in
terms of symmetric tracefree (STF) multipoles. In this investigation, the
post-linear metric density of this formalism is used in order to determine the
post-linear metric tensor in the exterior of a compact source of matter. The
metric tensor is given in harmonic coordinates and in terms of STF multipoles.
The post-linear metric coefficients are associated with an integration
procedure. The integration of these post-linear metric coefficients is
performed explicitly for the case of a stationary source, where the first
multipoles (monopole and quadrupole) of the source are taken into account.
These studies are a requirement for further investigations in the theory of
light propagation aiming at highly precise astrometric measurements in the
solar system, where the post-linear coefficients of the metric tensor of solar
system bodies become relevant.
| [
{
"created": "Mon, 21 Oct 2019 11:34:42 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Oct 2019 10:20:19 GMT",
"version": "v2"
}
] | 2019-10-30 | [
[
"Zschocke",
"Sven",
""
]
] | The Multipolar Post-Minkowskian (MPM) formalism represents an approach for determining the metric density in the exterior of a compact source of matter. In the MPM formalism the metric density is given in harmonic coordinates and in terms of symmetric tracefree (STF) multipoles. In this investigation, the post-linear metric density of this formalism is used in order to determine the post-linear metric tensor in the exterior of a compact source of matter. The metric tensor is given in harmonic coordinates and in terms of STF multipoles. The post-linear metric coefficients are associated with an integration procedure. The integration of these post-linear metric coefficients is performed explicitly for the case of a stationary source, where the first multipoles (monopole and quadrupole) of the source are taken into account. These studies are a requirement for further investigations in the theory of light propagation aiming at highly precise astrometric measurements in the solar system, where the post-linear coefficients of the metric tensor of solar system bodies become relevant. |
2311.11033 | Xiang-Hua Zhai | Ping Li, Yong-Qiang Liu and Xiang-Hua Zhai | Accretion of the relativistic Vlasov gas onto a Kerr black hole | 28 pages, 11 figures, accepted for publication in Physical Review D | null | null | null | gr-qc astro-ph.HE hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the accretion of relativistic Vlasov gas onto a Kerr black hole,
regarding the particles as distributed throughout all the space, other than
just in the equatorial plane. We solve the relativistic Liouville equation in
the full $3+1$ dimensional framework of Kerr geometry. For the flow that is
stationary and axial symmetric, we prove that the distribution function is
independent of the conjugate coordinates. For an explicit distribution that can
approximate to Maxwell-J\"{u}ttner distribution, we further calculate the
particle current density, the stress energy momentum tensor and the unit
accretion rates of mass, energy and angular momentum. The analytic results at
large distance are shown to be consistent with the limits of the numerical ones
computed at finite distance. Especially, we show that the unit mass accretion
rate agrees with the Schwarzschild result in the case of low temperature limit.
Furthermore, we find from the numerical results that the three unit accretion
rates vary with the angle in Kerr metric and the accretion of Vlasov gas would
slow down the Kerr black hole. The closer to the equator, the faster it slows
down the black hole.
| [
{
"created": "Sat, 18 Nov 2023 10:45:59 GMT",
"version": "v1"
}
] | 2023-11-21 | [
[
"Li",
"Ping",
""
],
[
"Liu",
"Yong-Qiang",
""
],
[
"Zhai",
"Xiang-Hua",
""
]
] | We study the accretion of relativistic Vlasov gas onto a Kerr black hole, regarding the particles as distributed throughout all the space, other than just in the equatorial plane. We solve the relativistic Liouville equation in the full $3+1$ dimensional framework of Kerr geometry. For the flow that is stationary and axial symmetric, we prove that the distribution function is independent of the conjugate coordinates. For an explicit distribution that can approximate to Maxwell-J\"{u}ttner distribution, we further calculate the particle current density, the stress energy momentum tensor and the unit accretion rates of mass, energy and angular momentum. The analytic results at large distance are shown to be consistent with the limits of the numerical ones computed at finite distance. Especially, we show that the unit mass accretion rate agrees with the Schwarzschild result in the case of low temperature limit. Furthermore, we find from the numerical results that the three unit accretion rates vary with the angle in Kerr metric and the accretion of Vlasov gas would slow down the Kerr black hole. The closer to the equator, the faster it slows down the black hole. |
2407.21349 | Sergei V. Ketov | Shunsuke Toyama and Sergei V. Ketov | Starobinsky inflation beyond the leading order | 13 pages, no figures, LaTeX; a reference added | null | null | IPMU24-0033 | gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | The Starobinsky model of cosmological inflation in four spacetime dimensions
is reviewed with the emphasis on impact of quantum gravity corrections. As a
specific example of the quantum corrections, the Grisaru-Zanon quartic
curvature terms in the gravitational effective action of closed superstrings
are chosen. Those quartic curvature terms are compared to the Bel-Robinson
tensor squared in a flat Friedman universe, and the upper bound on the
effective string coupling constant is found by demanding unitarity (causality)
and the absence of ghosts. It is found that the quantum corrections to the
observables (tilts) of the cosmic microwave background radiation in the
Starobinsky inflation may be of the same order of magnitude as the
next-to-next-to-next classical contributions in the Starobinsky model with
respect to the inverse powers of the e-folding number at the horizon crossing.
| [
{
"created": "Wed, 31 Jul 2024 05:40:44 GMT",
"version": "v1"
},
{
"created": "Sat, 3 Aug 2024 07:24:49 GMT",
"version": "v2"
}
] | 2024-08-06 | [
[
"Toyama",
"Shunsuke",
""
],
[
"Ketov",
"Sergei V.",
""
]
] | The Starobinsky model of cosmological inflation in four spacetime dimensions is reviewed with the emphasis on impact of quantum gravity corrections. As a specific example of the quantum corrections, the Grisaru-Zanon quartic curvature terms in the gravitational effective action of closed superstrings are chosen. Those quartic curvature terms are compared to the Bel-Robinson tensor squared in a flat Friedman universe, and the upper bound on the effective string coupling constant is found by demanding unitarity (causality) and the absence of ghosts. It is found that the quantum corrections to the observables (tilts) of the cosmic microwave background radiation in the Starobinsky inflation may be of the same order of magnitude as the next-to-next-to-next classical contributions in the Starobinsky model with respect to the inverse powers of the e-folding number at the horizon crossing. |
2309.05045 | Cheng-Yong Zhang | Cheng-Yong Zhang, Qian Chen, Yuxuan Liu, Yu Tian, Bin Wang, Hongbao
Zhang | Nonlinear self-interaction induced black hole bomb | 7 pages, 5 figures | null | null | null | gr-qc | http://creativecommons.org/licenses/by/4.0/ | We present the first alternative mechanisms to trigger black hole bomb
phenomena beyond the famous superradiant instability. By incorporating
nonlinear self-interaction into the massive charged scalar field in general
relativity, we discover that the allowed static solutions suggest two such
novel dynamic mechanisms, which are further confirmed by our numerical
simulations. The first one originates from the linearly unstable hairy black
hole, but the bomb can be avoided by dialing the coefficient of the tiny scalar
pulse. This distinguishes it from superradiant instability, where the bomb is
an inevitable destiny. The second one is an intrinsically nonlinear process,
which can even drive a linearly stable Reissner-Nordstr\"om black hole to
become a black hole bomb by releasing substantial energy to develop scalar
hair. This is also in sharp contrast with superradiant instability which can
only drive an unstable black hole. These findings not only open up new avenues
for black hole energy burst, but also have potential implications for new
phenomena occurring around astrophysical black holes.
| [
{
"created": "Sun, 10 Sep 2023 14:48:06 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Jul 2024 00:05:28 GMT",
"version": "v2"
}
] | 2024-07-15 | [
[
"Zhang",
"Cheng-Yong",
""
],
[
"Chen",
"Qian",
""
],
[
"Liu",
"Yuxuan",
""
],
[
"Tian",
"Yu",
""
],
[
"Wang",
"Bin",
""
],
[
"Zhang",
"Hongbao",
""
]
] | We present the first alternative mechanisms to trigger black hole bomb phenomena beyond the famous superradiant instability. By incorporating nonlinear self-interaction into the massive charged scalar field in general relativity, we discover that the allowed static solutions suggest two such novel dynamic mechanisms, which are further confirmed by our numerical simulations. The first one originates from the linearly unstable hairy black hole, but the bomb can be avoided by dialing the coefficient of the tiny scalar pulse. This distinguishes it from superradiant instability, where the bomb is an inevitable destiny. The second one is an intrinsically nonlinear process, which can even drive a linearly stable Reissner-Nordstr\"om black hole to become a black hole bomb by releasing substantial energy to develop scalar hair. This is also in sharp contrast with superradiant instability which can only drive an unstable black hole. These findings not only open up new avenues for black hole energy burst, but also have potential implications for new phenomena occurring around astrophysical black holes. |
gr-qc/0003079 | dhZhang | De-Hai Zhang (Graduate School, Academia Sinica) | Quantum Creation of Closed Universe with Both Effects of Tunneling and
Well | 8 pages, no figures, Latex | null | 10.1088/0253-6102/35/5/635 | GS-AS-000316 | gr-qc astro-ph hep-ph hep-th | null | A new ''twice loose shoe'' method in the Wheeler-DeWitt equation of the
universe wave function on the cosmic scale factor a and a scalar field $\phi$
is suggested in this letter. We analysis the both affects come from the
tunneling effect of a and the potential well effect of $\phi$, and obtain the
initial values $a_0$ and $\phi_0$ about a primary closed universe which is born
with the largest probability in the quantum manner. Our result is able to
overcome the ''large field difficulty'' of the universe quantum creation
probability with only tunneling effect. This new born universe has to suffer a
startup of inflation, and then comes into the usual slow rolling inflation. The
universe with the largest probability maybe has a ''gentle'' inflation or an
eternal chaotic inflation, this depends on a new parameter q which describes
the tunneling character.
| [
{
"created": "Mon, 20 Mar 2000 07:33:25 GMT",
"version": "v1"
}
] | 2018-01-17 | [
[
"Zhang",
"De-Hai",
"",
"Graduate School, Academia Sinica"
]
] | A new ''twice loose shoe'' method in the Wheeler-DeWitt equation of the universe wave function on the cosmic scale factor a and a scalar field $\phi$ is suggested in this letter. We analysis the both affects come from the tunneling effect of a and the potential well effect of $\phi$, and obtain the initial values $a_0$ and $\phi_0$ about a primary closed universe which is born with the largest probability in the quantum manner. Our result is able to overcome the ''large field difficulty'' of the universe quantum creation probability with only tunneling effect. This new born universe has to suffer a startup of inflation, and then comes into the usual slow rolling inflation. The universe with the largest probability maybe has a ''gentle'' inflation or an eternal chaotic inflation, this depends on a new parameter q which describes the tunneling character. |
2105.07589 | Pitayuth Wongjun | P. Boonserm, C. H. Chen, T. Ngampitipan, and P. Wongjun | Greybody factor for massive fermion emitted by a black hole in dRGT
massive gravity theory | 40 pages, 16 figures, 1 table; V2 added Ref | null | 10.1103/PhysRevD.104.084054 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The greybody factor of the massive Dirac field around the black hole in the
dRGT massive gravity theory is investigated using the rigorous bound and the
WKB approximation methods. In both methods, the greybody factor significantly
depends on the shape of the potential. If the potential is smaller, there is
more probability for the Dirac field to transmit through the black hole,
therefore, the greybody factor is higher. Moreover, there exists a critical
mass of the Dirac field such that the greybody factor is maximum. By comparing
the results from these two methods, we argue that it is useful to use the
rigorous bound method for the low potential cases, while using the WKB
approximation method for the high potential cases.
| [
{
"created": "Mon, 17 May 2021 03:23:18 GMT",
"version": "v1"
},
{
"created": "Tue, 25 May 2021 03:53:36 GMT",
"version": "v2"
}
] | 2021-10-27 | [
[
"Boonserm",
"P.",
""
],
[
"Chen",
"C. H.",
""
],
[
"Ngampitipan",
"T.",
""
],
[
"Wongjun",
"P.",
""
]
] | The greybody factor of the massive Dirac field around the black hole in the dRGT massive gravity theory is investigated using the rigorous bound and the WKB approximation methods. In both methods, the greybody factor significantly depends on the shape of the potential. If the potential is smaller, there is more probability for the Dirac field to transmit through the black hole, therefore, the greybody factor is higher. Moreover, there exists a critical mass of the Dirac field such that the greybody factor is maximum. By comparing the results from these two methods, we argue that it is useful to use the rigorous bound method for the low potential cases, while using the WKB approximation method for the high potential cases. |
gr-qc/9403042 | Donald Marolf | Abhay Ashtekar, Donald Marolf, and Jose Mourao | Integration on the space of Connections Modulo Gauge Transformations | 18 pages, CGPG-94/3-4, References added and typographic mistakes
revised | Proc. of the Cornelius Lanczos Centenary Conference ed. by J.D.
Brown et. al. (SIAM, Philadelphia, 1994) | null | null | gr-qc hep-th | null | A summary of the known results on integration theory on the space of
connections modulo gauge transformations is presented and its significance to
quantum theories of gauge fields and gravity is discussed. The emphasis is on
the underlying ideas rather than the technical subtleties.
| [
{
"created": "Tue, 22 Mar 1994 02:38:02 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Mar 1994 20:56:39 GMT",
"version": "v2"
},
{
"created": "Tue, 5 Apr 1994 16:08:12 GMT",
"version": "v3"
}
] | 2008-02-03 | [
[
"Ashtekar",
"Abhay",
""
],
[
"Marolf",
"Donald",
""
],
[
"Mourao",
"Jose",
""
]
] | A summary of the known results on integration theory on the space of connections modulo gauge transformations is presented and its significance to quantum theories of gauge fields and gravity is discussed. The emphasis is on the underlying ideas rather than the technical subtleties. |
1408.0790 | Cornelius Rampf | Florian Kuhnel and Cornelius Rampf | Astrophysical Bose-Einstein Condensates and Superradiance | 11 pages, 3 figures, version published in PRD | Phys. Rev. D 90, 103526 (2014) | 10.1103/PhysRevD.90.103526 | null | gr-qc astro-ph.CO astro-ph.GA cond-mat.other | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate gravitational analogue models to describe slowly rotating
objects (e.g., dark-matter halos, or boson stars) in terms of Bose-Einstein
condensates, trapped in their own gravitational potentials. We begin with a
modified Gross-Pitaevskii equation, and show that the resulting background
equations of motion are stable, as long as the rotational component is treated
as a small perturbation. The dynamics of the fluctuations of the velocity
potential are effectively governed by the Klein-Gordon equation of a "Eulerian
metric," where we derive the latter by the use of a relativistic Lagrangian
extrapolation. Superradiant scattering on such objects is studied. We derive
conditions for its occurence and estimate its strength. Our investigations
might give an observational handle to phenomenologically constrain
Bose-Einstein condensates.
| [
{
"created": "Mon, 4 Aug 2014 19:59:55 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Nov 2014 21:00:35 GMT",
"version": "v2"
}
] | 2014-11-26 | [
[
"Kuhnel",
"Florian",
""
],
[
"Rampf",
"Cornelius",
""
]
] | We investigate gravitational analogue models to describe slowly rotating objects (e.g., dark-matter halos, or boson stars) in terms of Bose-Einstein condensates, trapped in their own gravitational potentials. We begin with a modified Gross-Pitaevskii equation, and show that the resulting background equations of motion are stable, as long as the rotational component is treated as a small perturbation. The dynamics of the fluctuations of the velocity potential are effectively governed by the Klein-Gordon equation of a "Eulerian metric," where we derive the latter by the use of a relativistic Lagrangian extrapolation. Superradiant scattering on such objects is studied. We derive conditions for its occurence and estimate its strength. Our investigations might give an observational handle to phenomenologically constrain Bose-Einstein condensates. |
gr-qc/9511030 | Renate Loll | R. Loll (INFN, Firenze) | Spectrum of the Volume Operator in Quantum Gravity | 14 pages, plain tex, 4 figures (postscript, compressed and
uu-encoded) | Nucl.Phys. B460 (1996) 143-154 | 10.1016/0550-3213(95)00627-3 | DFF 235/11/95 | gr-qc hep-th | null | The volume operator is an important kinematical quantity in the
non-perturbative approach to four-dimensional quantum gravity in the connection
formulation. We give a general algorithm for computing its spectrum when acting
on four-valent spin network states, evaluate some of the eigenvalue formulae
explicitly, and discuss the role played by the Mandelstam constraints.
| [
{
"created": "Thu, 9 Nov 1995 16:47:39 GMT",
"version": "v1"
}
] | 2016-08-31 | [
[
"Loll",
"R.",
"",
"INFN, Firenze"
]
] | The volume operator is an important kinematical quantity in the non-perturbative approach to four-dimensional quantum gravity in the connection formulation. We give a general algorithm for computing its spectrum when acting on four-valent spin network states, evaluate some of the eigenvalue formulae explicitly, and discuss the role played by the Mandelstam constraints. |
0905.2662 | Muhammad Sharif | M. Sharif and Sajid Sultan | Tilted Cylindrically Symmetric Self-Similar Solutions | 17 pages, accepted for publication in Acta Physica Polonica B | Acta Phys.Polon.B40:1553-1568,2009 | null | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper is devoted to explore tilted kinematic self-similar solutions of
the the general cylindrical symmetric spacetimes. These solutions are of the
first, zeroth, second and infinite kinds for the perfect fluid and dust cases.
Three different equations of state are used to obtain these solutions. We
obtain a total of five independent solutions. The correspondence of these
solutions with those already available in the literature is also given.
| [
{
"created": "Sat, 16 May 2009 07:44:34 GMT",
"version": "v1"
}
] | 2009-07-24 | [
[
"Sharif",
"M.",
""
],
[
"Sultan",
"Sajid",
""
]
] | This paper is devoted to explore tilted kinematic self-similar solutions of the the general cylindrical symmetric spacetimes. These solutions are of the first, zeroth, second and infinite kinds for the perfect fluid and dust cases. Three different equations of state are used to obtain these solutions. We obtain a total of five independent solutions. The correspondence of these solutions with those already available in the literature is also given. |
1408.4431 | Philippe G. LeFloch | Dan A. Lee and Philippe G. LeFloch | The positive mass theorem for manifolds with distributional curvature | 26 pages | null | null | null | gr-qc math.AP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We formulate and prove a positive mass theorem for n-dimensional spin
manifolds whose metrics have only the Sobolev regularity $C^0 \cap W^{1,n}$. At
this level of regularity, the curvature of the metric is defined in the
distributional sense only, and we propose here a (generalized) notion of ADM
mass for such a metric. Our main theorem establishes that if the manifold is
asymptotically flat and has non-negative scalar curvature distribution, then
its (generalized) ADM mass is well-defined and non-negative, and vanishes only
if the manifold is isometric to Euclidian space. Prior applications of Witten's
spinor method by Lee and Parker and by Bartnik required the much stronger
regularity $W^{2,2}$. Our proof is a generalization of Witten's arguments, in
which we must treat the Dirac operator and its associated
Lichnerowicz-Weitzenbock identity in the distributional sense and cope with
certain averages of first-order derivatives of the metric over annuli that
approach infinity. Finally, we observe that our arguments are not specific to
scalar curvature and also allow us to establish a universal positive mass
theorem.
| [
{
"created": "Tue, 19 Aug 2014 19:17:53 GMT",
"version": "v1"
}
] | 2014-08-20 | [
[
"Lee",
"Dan A.",
""
],
[
"LeFloch",
"Philippe G.",
""
]
] | We formulate and prove a positive mass theorem for n-dimensional spin manifolds whose metrics have only the Sobolev regularity $C^0 \cap W^{1,n}$. At this level of regularity, the curvature of the metric is defined in the distributional sense only, and we propose here a (generalized) notion of ADM mass for such a metric. Our main theorem establishes that if the manifold is asymptotically flat and has non-negative scalar curvature distribution, then its (generalized) ADM mass is well-defined and non-negative, and vanishes only if the manifold is isometric to Euclidian space. Prior applications of Witten's spinor method by Lee and Parker and by Bartnik required the much stronger regularity $W^{2,2}$. Our proof is a generalization of Witten's arguments, in which we must treat the Dirac operator and its associated Lichnerowicz-Weitzenbock identity in the distributional sense and cope with certain averages of first-order derivatives of the metric over annuli that approach infinity. Finally, we observe that our arguments are not specific to scalar curvature and also allow us to establish a universal positive mass theorem. |
0806.1731 | Slava G. Turyshev | Slava G. Turyshev | Experimental Tests of General Relativity | revtex4, 30 pages, 10 figures | Ann.Rev.Nucl.Part.Sci.58:207-248,2008 | 10.1146/annurev.nucl.58.020807.111839 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Einstein's general theory of relativity is the standard theory of gravity,
especially where the needs of astronomy, astrophysics, cosmology and
fundamental physics are concerned. As such, this theory is used for many
practical purposes involving spacecraft navigation, geodesy, and time transfer.
Here I review the foundations of general relativity, discuss recent progress in
the tests of relativistic gravity in the solar system, and present motivations
for the new generation of high-accuracy gravitational experiments. I discuss
the advances in our understanding of fundamental physics that are anticipated
in the near future and evaluate the discovery potential of the recently
proposed gravitational experiments.
| [
{
"created": "Tue, 10 Jun 2008 19:57:33 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Jun 2008 19:32:48 GMT",
"version": "v2"
}
] | 2011-08-17 | [
[
"Turyshev",
"Slava G.",
""
]
] | Einstein's general theory of relativity is the standard theory of gravity, especially where the needs of astronomy, astrophysics, cosmology and fundamental physics are concerned. As such, this theory is used for many practical purposes involving spacecraft navigation, geodesy, and time transfer. Here I review the foundations of general relativity, discuss recent progress in the tests of relativistic gravity in the solar system, and present motivations for the new generation of high-accuracy gravitational experiments. I discuss the advances in our understanding of fundamental physics that are anticipated in the near future and evaluate the discovery potential of the recently proposed gravitational experiments. |
1607.03507 | Muhammad Sharif | M. Sharif and Sehrish Iftikhar | Dynamics of Particles Near Black Hole with Higher Dimensions | 19 pages, 3 figure, to appear in EPJC | Eur. Phys. J. C 76(2016)404 | 10.1140/epjc/s10052-016-4244-0 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper explores the dynamics of particles in higher dimensions. For this
purpose, we discuss some interesting features related to the motion of
particles near Myers-Perry black hole with arbitrary extra dimensions as well
as single non-zero spin parameter. Assuming it as a supermassive black hole at
the center of galaxy, we calculate red-blue shifts in the equatorial plane for
the far away observer as well as corresponding black hole parameters of the
photons. Next, we study the Penrose process and find that the energy gain of
particle depends on the variation of black hole dimensions. Finally, we discuss
the center of mass energy for eleven dimensions which indicates similar
behavior as that of four dimensions but it is higher in four dimensions than
five or more dimensions. We conclude that higher dimensions have a great impact
on the particle dynamics.
| [
{
"created": "Fri, 1 Jul 2016 02:24:49 GMT",
"version": "v1"
}
] | 2016-08-24 | [
[
"Sharif",
"M.",
""
],
[
"Iftikhar",
"Sehrish",
""
]
] | This paper explores the dynamics of particles in higher dimensions. For this purpose, we discuss some interesting features related to the motion of particles near Myers-Perry black hole with arbitrary extra dimensions as well as single non-zero spin parameter. Assuming it as a supermassive black hole at the center of galaxy, we calculate red-blue shifts in the equatorial plane for the far away observer as well as corresponding black hole parameters of the photons. Next, we study the Penrose process and find that the energy gain of particle depends on the variation of black hole dimensions. Finally, we discuss the center of mass energy for eleven dimensions which indicates similar behavior as that of four dimensions but it is higher in four dimensions than five or more dimensions. We conclude that higher dimensions have a great impact on the particle dynamics. |
0803.3710 | Christodoulakis Theodosios | Petros A. Terzis, T. Cristodoulakis | The General Solution of Bianchi Type $VII_h$ Vacuum Cosmology | latex2e source file, 27 pages, 2 tables, no fiures | Gen.Rel.Grav. 41 (2009) 469-495 | 10.1007/s10714-008-0678-5 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The theory of symmetries of systems of coupled, ordinary differential
equations (ODE) is used to develop a concise algorithm in order to obtain the
entire space of solutions to vacuum Bianchi Einstein Field Equations (EFEs).
The symmetries used are the well known automorphisms of the Lie algebra for the
corresponding isometry group of each Bianchi Type, as well as the scaling and
the time re-parametrization symmetry. The application of the method to Type
VII_h results in (a) obtaining the general solution of Type VII_0 with the aid
of the third Painlev\'{e} transcendental (b) obtaining the general solution of
Type $VII_h$ with the aid of the sixth Painlev\'{e} transcendental (c) the
recovery of all known solutions (six in total) without a prior assumption of
any extra symmetry (d) The discovery of a new solution (the line element given
in closed form) with a G_3 isometry group acting on T_3, i.e. on time-like
hyper-surfaces, along with the emergence of the line element describing the
flat vacuum Type VII_0 Bianchi Cosmology.
| [
{
"created": "Wed, 26 Mar 2008 12:15:14 GMT",
"version": "v1"
}
] | 2013-05-06 | [
[
"Terzis",
"Petros A.",
""
],
[
"Cristodoulakis",
"T.",
""
]
] | The theory of symmetries of systems of coupled, ordinary differential equations (ODE) is used to develop a concise algorithm in order to obtain the entire space of solutions to vacuum Bianchi Einstein Field Equations (EFEs). The symmetries used are the well known automorphisms of the Lie algebra for the corresponding isometry group of each Bianchi Type, as well as the scaling and the time re-parametrization symmetry. The application of the method to Type VII_h results in (a) obtaining the general solution of Type VII_0 with the aid of the third Painlev\'{e} transcendental (b) obtaining the general solution of Type $VII_h$ with the aid of the sixth Painlev\'{e} transcendental (c) the recovery of all known solutions (six in total) without a prior assumption of any extra symmetry (d) The discovery of a new solution (the line element given in closed form) with a G_3 isometry group acting on T_3, i.e. on time-like hyper-surfaces, along with the emergence of the line element describing the flat vacuum Type VII_0 Bianchi Cosmology. |
1101.5396 | Holger Pletsch | Holger J. Pletsch | Sliding coherence window technique for hierarchical detection of
continuous gravitational waves | 11 pages, 4 figures | Phys.Rev.D83:122003,2011 | 10.1103/PhysRevD.83.122003 | LIGO-P1000130-v3, AEI-2010-181 | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A novel hierarchical search technique is presented for all-sky surveys for
continuous gravitational-wave sources, such as rapidly spinning nonaxisymmetric
neutron stars. Analyzing yearlong detector data sets over realistic ranges of
parameter space using fully coherent matched-filtering is computationally
prohibitive. Thus more efficient, so-called hierarchical techniques are
essential. Traditionally, the standard hierarchical approach consists of
dividing the data into nonoverlapping segments of which each is coherently
analyzed and subsequently the matched-filter outputs from all segments are
combined incoherently. The present work proposes to break the data into
subsegments shorter than the desired maximum coherence time span (size of the
coherence window). Then matched-filter outputs from the different subsegments
are efficiently combined by sliding the coherence window in time: Subsegments
whose timestamps are closer than coherence window size are combined coherently,
otherwise incoherently. Compared to the standard scheme at the same coherence
time baseline, data sets longer by about 50-100% would have to be analyzed to
achieve the same search sensitivity as with the sliding coherence window
approach. Numerical simulations attest to the analytically estimated
improvement.
| [
{
"created": "Thu, 27 Jan 2011 21:11:23 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Jun 2011 09:24:23 GMT",
"version": "v2"
}
] | 2015-03-18 | [
[
"Pletsch",
"Holger J.",
""
]
] | A novel hierarchical search technique is presented for all-sky surveys for continuous gravitational-wave sources, such as rapidly spinning nonaxisymmetric neutron stars. Analyzing yearlong detector data sets over realistic ranges of parameter space using fully coherent matched-filtering is computationally prohibitive. Thus more efficient, so-called hierarchical techniques are essential. Traditionally, the standard hierarchical approach consists of dividing the data into nonoverlapping segments of which each is coherently analyzed and subsequently the matched-filter outputs from all segments are combined incoherently. The present work proposes to break the data into subsegments shorter than the desired maximum coherence time span (size of the coherence window). Then matched-filter outputs from the different subsegments are efficiently combined by sliding the coherence window in time: Subsegments whose timestamps are closer than coherence window size are combined coherently, otherwise incoherently. Compared to the standard scheme at the same coherence time baseline, data sets longer by about 50-100% would have to be analyzed to achieve the same search sensitivity as with the sliding coherence window approach. Numerical simulations attest to the analytically estimated improvement. |
1011.1325 | Raymond Chiao Y. | R. Y. Chiao | Figure "8" gravitational-wave antenna using a superconducting-core
coaxial cable: Continuity equation and its superluminal consequences | White paper, 17 pages, 3 figures | null | null | null | gr-qc quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A novel gravitational-wave antenna is proposed based on the prediction that
supercurrents induced by gravitational waves in a superconductor that is bent
into the shape of a figure "8" will couple efficiently to such waves.
| [
{
"created": "Fri, 5 Nov 2010 06:01:40 GMT",
"version": "v1"
}
] | 2010-11-08 | [
[
"Chiao",
"R. Y.",
""
]
] | A novel gravitational-wave antenna is proposed based on the prediction that supercurrents induced by gravitational waves in a superconductor that is bent into the shape of a figure "8" will couple efficiently to such waves. |
1201.1827 | Yousef Bisabr | Yousef Bisabr (Farzan-Nahad) | Cosmic Evolution in a Modified Brans-Dicke Theory | 11 pages, 3 figures, To appear in Astrophysics and Space Science | Astrophys Space Sci (2012) 339:87-92 | 10.1007/s10509-012-0976-y | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider Brans-Dicke theory with a self-interacting potential in Einstein
conformal frame. We introduce a class of solutions in which an accelerating
expansion is possible in a spatially flat universe for positive and large
values of the Brans-Dicke parameter consistent with local gravity experiments.
In this Einstein frame formulation, the theory appears as an interacting
quintessence model in which the interaction term is given by the conformal
transformation. In such an interacting model, we shall show that the solutions
lead simultaneously to a constant ratio of energy densities of matter and the
scalar field.
| [
{
"created": "Mon, 9 Jan 2012 16:23:52 GMT",
"version": "v1"
}
] | 2012-05-03 | [
[
"Bisabr",
"Yousef",
"",
"Farzan-Nahad"
]
] | We consider Brans-Dicke theory with a self-interacting potential in Einstein conformal frame. We introduce a class of solutions in which an accelerating expansion is possible in a spatially flat universe for positive and large values of the Brans-Dicke parameter consistent with local gravity experiments. In this Einstein frame formulation, the theory appears as an interacting quintessence model in which the interaction term is given by the conformal transformation. In such an interacting model, we shall show that the solutions lead simultaneously to a constant ratio of energy densities of matter and the scalar field. |
gr-qc/9705030 | A. Mikovic | A. Mikovic | General Solution for Self-Gravitating Spherical Null Dust | 9 pages, Latex, 1 figure | Phys.Rev.D56:6067-6070,1997 | 10.1103/PhysRevD.56.R6067 | FTUV-97-24 | gr-qc hep-th | null | We find the general solution of equations of motion for self-gravitating
spherical null dust as a perturbative series in powers of the outgoing matter
energy-momentum tensor, with the lowest order term being the Vaidya solution
for the ingoing matter. This is done by representing the null-dust model as a
2d dilaton gravity theory, and by using a symmetry of a pure 2d dilaton gravity
to fix the gauge. Quantization of this solution would provide an effective
metric which includes the back-reaction for a more realistic black hole
evaporation model than the evaporation models studied previously.
| [
{
"created": "Tue, 13 May 1997 13:03:09 GMT",
"version": "v1"
}
] | 2009-01-16 | [
[
"Mikovic",
"A.",
""
]
] | We find the general solution of equations of motion for self-gravitating spherical null dust as a perturbative series in powers of the outgoing matter energy-momentum tensor, with the lowest order term being the Vaidya solution for the ingoing matter. This is done by representing the null-dust model as a 2d dilaton gravity theory, and by using a symmetry of a pure 2d dilaton gravity to fix the gauge. Quantization of this solution would provide an effective metric which includes the back-reaction for a more realistic black hole evaporation model than the evaporation models studied previously. |
1909.11011 | Antoni Ramos Buades | Antoni Ramos-Buades, Sascha Husa, Geraint Pratten, H\'ector
Estell\'es, Cecilio Garc\'ia-Quir\'os, Maite Mateu-Lucena, Marta Colleoni and
Rafel Jaume | A first survey of spinning eccentric black hole mergers: Numerical
relativity simulations, hybrid waveforms, and parameter estimation | Matching published version | Phys. Rev. D 101, 083015 (2020) | 10.1103/PhysRevD.101.083015 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze a new numerical relativity dataset of spinning but nonprecessing
binary black holes on eccentric orbits, with eccentricities from approximately
$0.1$ to $0.5$, with dimensionless spins up to $0.75$ included at mass ratios
$q=m_1/m_2 = (1, 2)$, and further nonspinning binaries at mass ratios $q =
(1.5, 3, 4)$. A comparison of the final mass and spin of these simulations with
noneccentric data extends previous results in the literature on circularization
of eccentric binaries to the spinning case. For the $(l,m)=(2,2)$ spin-weighted
spherical harmonic mode we construct eccentric hybrid waveforms that connect
the numerical relativity data to a post-Newtonian description for the inspiral,
and we discuss the limitations in the current knowledge about post-Newtonian
theory which complicate the generation of eccentric hybrid waveforms. We also
perform a Bayesian parameter estimation study, quantifying the parameter biases
introduced when using three different quasicircular waveform models to estimate
the parameters of highly eccentric binary systems. We find that the used
aligned-spin quasicircular model including higher order modes produces lower
bias in certain parameters than the nonprecessing quasicircular model without
higher order modes and the quasicircular precessing model.
| [
{
"created": "Tue, 24 Sep 2019 15:46:42 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Apr 2020 10:30:45 GMT",
"version": "v2"
}
] | 2020-04-14 | [
[
"Ramos-Buades",
"Antoni",
""
],
[
"Husa",
"Sascha",
""
],
[
"Pratten",
"Geraint",
""
],
[
"Estellés",
"Héctor",
""
],
[
"García-Quirós",
"Cecilio",
""
],
[
"Mateu-Lucena",
"Maite",
""
],
[
"Colleoni",
"Marta",
""
],
[
"Jaume",
"Rafel",
""
]
] | We analyze a new numerical relativity dataset of spinning but nonprecessing binary black holes on eccentric orbits, with eccentricities from approximately $0.1$ to $0.5$, with dimensionless spins up to $0.75$ included at mass ratios $q=m_1/m_2 = (1, 2)$, and further nonspinning binaries at mass ratios $q = (1.5, 3, 4)$. A comparison of the final mass and spin of these simulations with noneccentric data extends previous results in the literature on circularization of eccentric binaries to the spinning case. For the $(l,m)=(2,2)$ spin-weighted spherical harmonic mode we construct eccentric hybrid waveforms that connect the numerical relativity data to a post-Newtonian description for the inspiral, and we discuss the limitations in the current knowledge about post-Newtonian theory which complicate the generation of eccentric hybrid waveforms. We also perform a Bayesian parameter estimation study, quantifying the parameter biases introduced when using three different quasicircular waveform models to estimate the parameters of highly eccentric binary systems. We find that the used aligned-spin quasicircular model including higher order modes produces lower bias in certain parameters than the nonprecessing quasicircular model without higher order modes and the quasicircular precessing model. |
1802.04001 | Sheyda Najafi | Sh. Najafi, M. T. Mirtorabi, Z. Ansari, D. F. Mota | Red Giant evolution in Modified Gravity | 27 pages, 15 figures | null | 10.1088/1475-7516/2019/02/011 | null | gr-qc astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we study the chameleon profile in inhomogeneous density
distributions and find that the fifth force in thin shell near the surface is
weaker from what expected in homogeneous density distributions. Also, we check
the validity of quasi-static approximation for the chameleon scalar field in
the astrophysical time scales. We have investigated the rolling down behaviour
of the scalar field on its effective potential inside a one solar mass red
giant star by using MESA code. We have found that the scalar field is fast
enough to follow the minimum of the potential. This adiabatic behaviour reduces
the fifth force and extends the screened regions to lower densities where the
field has smaller mass and was expected to be unscreened. As a consequence, the
star evolution is similar to what expected from standard general relativity. In
addition, considering the stability of star, an approximate constraint on the
coupling constant $\beta$ is found.
| [
{
"created": "Mon, 12 Feb 2018 12:11:07 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Feb 2018 17:20:16 GMT",
"version": "v2"
},
{
"created": "Mon, 23 Jul 2018 13:12:24 GMT",
"version": "v3"
},
{
"created": "Mon, 4 Feb 2019 18:53:12 GMT",
"version": "v4"
}
] | 2019-02-20 | [
[
"Najafi",
"Sh.",
""
],
[
"Mirtorabi",
"M. T.",
""
],
[
"Ansari",
"Z.",
""
],
[
"Mota",
"D. F.",
""
]
] | In this paper, we study the chameleon profile in inhomogeneous density distributions and find that the fifth force in thin shell near the surface is weaker from what expected in homogeneous density distributions. Also, we check the validity of quasi-static approximation for the chameleon scalar field in the astrophysical time scales. We have investigated the rolling down behaviour of the scalar field on its effective potential inside a one solar mass red giant star by using MESA code. We have found that the scalar field is fast enough to follow the minimum of the potential. This adiabatic behaviour reduces the fifth force and extends the screened regions to lower densities where the field has smaller mass and was expected to be unscreened. As a consequence, the star evolution is similar to what expected from standard general relativity. In addition, considering the stability of star, an approximate constraint on the coupling constant $\beta$ is found. |
1510.08706 | Johannes Th\"urigen | Johannes Th\"urigen | Discrete quantum geometries and their effective dimension | PhD thesis, Humboldt-Universit\"at zu Berlin;
urn:nbn:de:kobv:11-100232371;
http://edoc.hu-berlin.de/docviews/abstract.php?id=42042 | null | 10.18452/17309 | null | gr-qc hep-th physics.hist-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In several approaches towards a quantum theory of gravity, such as group
field theory and loop quantum gravity, quantum states and histories of the
geometric degrees of freedom turn out to be based on discrete spacetime. The
most pressing issue is then how the smooth geometries of general relativity,
expressed in terms of suitable geometric observables, arise from such discrete
quantum geometries in some semiclassical and continuum limit. In this thesis I
tackle the question of suitable observables focusing on the effective dimension
of discrete quantum geometries. For this purpose I give a purely combinatorial
description of the discrete structures which these geometries have support on.
As a side topic, this allows to present an extension of group field theory to
cover the combinatorially larger kinematical state space of loop quantum
gravity. Moreover, I introduce a discrete calculus for fields on such
fundamentally discrete geometries with a particular focus on the Laplacian.
This permits to define the effective-dimension observables for quantum
geometries. Analysing various classes of quantum geometries, I find as a
general result that the spectral dimension is more sensitive to the underlying
combinatorial structure than to the details of the additional geometric data
thereon. Semiclassical states in loop quantum gravity approximate the classical
geometries they are peaking on rather well and there are no indications for
stronger quantum effects. On the other hand, in the context of a more general
model of states which are superposition over a large number of complexes, based
on analytic solutions, there is a flow of the spectral dimension from the
topological dimension $d$ on low energy scales to a real number $0<\alpha<d$ on
high energy scales. In the particular case of $\alpha=1$ these results allow to
understand the quantum geometry as effectively fractal.
| [
{
"created": "Thu, 29 Oct 2015 14:30:07 GMT",
"version": "v1"
}
] | 2018-08-01 | [
[
"Thürigen",
"Johannes",
""
]
] | In several approaches towards a quantum theory of gravity, such as group field theory and loop quantum gravity, quantum states and histories of the geometric degrees of freedom turn out to be based on discrete spacetime. The most pressing issue is then how the smooth geometries of general relativity, expressed in terms of suitable geometric observables, arise from such discrete quantum geometries in some semiclassical and continuum limit. In this thesis I tackle the question of suitable observables focusing on the effective dimension of discrete quantum geometries. For this purpose I give a purely combinatorial description of the discrete structures which these geometries have support on. As a side topic, this allows to present an extension of group field theory to cover the combinatorially larger kinematical state space of loop quantum gravity. Moreover, I introduce a discrete calculus for fields on such fundamentally discrete geometries with a particular focus on the Laplacian. This permits to define the effective-dimension observables for quantum geometries. Analysing various classes of quantum geometries, I find as a general result that the spectral dimension is more sensitive to the underlying combinatorial structure than to the details of the additional geometric data thereon. Semiclassical states in loop quantum gravity approximate the classical geometries they are peaking on rather well and there are no indications for stronger quantum effects. On the other hand, in the context of a more general model of states which are superposition over a large number of complexes, based on analytic solutions, there is a flow of the spectral dimension from the topological dimension $d$ on low energy scales to a real number $0<\alpha<d$ on high energy scales. In the particular case of $\alpha=1$ these results allow to understand the quantum geometry as effectively fractal. |
2007.09169 | Jiri Podolsky | Jiri Podolsky, Adam Vratny | Accelerating NUT black holes | 37 pages, 6 figures | Phys. Rev. D 102, 084024 (2020) | 10.1103/PhysRevD.102.084024 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present and analyze a class of exact spacetimes which describe
accelerating black holes with a NUT parameter. First, we verify that the
intricate metric found by Chng, Mann and Stelea in 2006 indeed solves
Einstein's vacuum field equations of General Relativity. We explicitly
calculate all components of the Weyl tensor and determine its algebraic
structure. As it turns out, it is actually of algebraically general type I with
four distinct principal null directions. It explains why this class of
solutions has not been (and could not be) found within the large
Plebanski-Demianski family of type D spacetimes. Then we transform the solution
into a much more convenient metric form which explicitly depends on three
physical parameters: mass, acceleration, and the NUT parameter. These
parameters can independently be set to zero, recovering thus the well-known
spacetimes in standard coordinates, namely the C-metric, the Taub-NUT metric,
the Schwarzschild metric, and flat Minkowski space. Using this new metric, we
investigate physical and geometrical properties of such accelerating NUT black
holes. In particular, we localize and study four Killing horizons (two
black-hole plus two acceleration) and investigate the curvature. Employing the
scalar invariants we prove that there are no curvature singularities whenever
the NUT parameter is nonzero. We identify asymptotically flat regions and
relate them to conformal infinities. This leads to a complete understanding of
the global structure. The boost-rotation metric form reveals that there is
actually a pair of such black holes. They uniformly accelerate in opposite
directions due to the action of rotating cosmic strings or struts located along
the corresponding two axes. Rotation of these sources is directly related to
the NUT parameter. In their vicinity there are pathological regions with closed
timelike curves.
| [
{
"created": "Fri, 17 Jul 2020 18:12:48 GMT",
"version": "v1"
}
] | 2020-10-14 | [
[
"Podolsky",
"Jiri",
""
],
[
"Vratny",
"Adam",
""
]
] | We present and analyze a class of exact spacetimes which describe accelerating black holes with a NUT parameter. First, we verify that the intricate metric found by Chng, Mann and Stelea in 2006 indeed solves Einstein's vacuum field equations of General Relativity. We explicitly calculate all components of the Weyl tensor and determine its algebraic structure. As it turns out, it is actually of algebraically general type I with four distinct principal null directions. It explains why this class of solutions has not been (and could not be) found within the large Plebanski-Demianski family of type D spacetimes. Then we transform the solution into a much more convenient metric form which explicitly depends on three physical parameters: mass, acceleration, and the NUT parameter. These parameters can independently be set to zero, recovering thus the well-known spacetimes in standard coordinates, namely the C-metric, the Taub-NUT metric, the Schwarzschild metric, and flat Minkowski space. Using this new metric, we investigate physical and geometrical properties of such accelerating NUT black holes. In particular, we localize and study four Killing horizons (two black-hole plus two acceleration) and investigate the curvature. Employing the scalar invariants we prove that there are no curvature singularities whenever the NUT parameter is nonzero. We identify asymptotically flat regions and relate them to conformal infinities. This leads to a complete understanding of the global structure. The boost-rotation metric form reveals that there is actually a pair of such black holes. They uniformly accelerate in opposite directions due to the action of rotating cosmic strings or struts located along the corresponding two axes. Rotation of these sources is directly related to the NUT parameter. In their vicinity there are pathological regions with closed timelike curves. |
1904.07670 | Behzad Eslam Panah | B. Eslam Panah, and S. H. Hendi | Black hole solutions correspondence between conformal and massive
theories of gravity | 7 pages, 1 figure | EPL 125, 60006 (2019) | 10.1209/0295-5075/125/60006 | null | gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, a correspondence between black hole solutions of conformal and
massive theories of gravity is found. It is seen that this correspondence
imposes some constraints on parameters of these theories. What is more, a
relation between the mass of black holes and the parameters of massive gravity
is found. Indeed, the acceptable ranges of massive gravity parameters ($c_{1}$\
and $c_{2}$) are found. It is shown that by considering the positive mass of
black holes, some ranges of $c_{1}$\ and $c_{2}$ are acceptable.
| [
{
"created": "Mon, 15 Apr 2019 07:34:44 GMT",
"version": "v1"
},
{
"created": "Thu, 30 May 2019 08:05:00 GMT",
"version": "v2"
}
] | 2019-05-31 | [
[
"Panah",
"B. Eslam",
""
],
[
"Hendi",
"S. H.",
""
]
] | In this work, a correspondence between black hole solutions of conformal and massive theories of gravity is found. It is seen that this correspondence imposes some constraints on parameters of these theories. What is more, a relation between the mass of black holes and the parameters of massive gravity is found. Indeed, the acceptable ranges of massive gravity parameters ($c_{1}$\ and $c_{2}$) are found. It is shown that by considering the positive mass of black holes, some ranges of $c_{1}$\ and $c_{2}$ are acceptable. |
2407.09589 | Sai Swagat Mishra | N. S. Kavya, Sai Swagat Mishra, P.K. Sahoo, V. Venkatesha | Can $f(T)$ models play a bridge between early and late time Universe? | MNRAS accepted version | Monthly Notices of the Royal Astronomical Society, 532(3) (2024)
3126 | 10.1093/mnras/stae1723 | null | gr-qc astro-ph.CO | http://creativecommons.org/licenses/by-nc-sa/4.0/ | The ability of Big Bang Nucleosynthesis theory to accurately predict the
primordial abundances of helium and deuterium, as well as the baryon content of
the Universe, is considered one of the most significant achievements in modern
physics. In the present study, we consider two highly motivated hybrid $f(T)$
models and constrain them using the observations from the Big Bang
Nucleosynthesis era. In addition, using late-time observations of Cosmic
Chronometers and Gamma-Ray-Bursts, the ranges of the model parameters are
confined which are in good agreement with early time bounds. Subsequently, the
common ranges obtained from the analysis for early and late time are
summarized. Further, we verify the intermediating epochs by investigating the
profiles of cosmographic parameters using the model parameter values from the
common range. From this study, we find the considered teleparallel models are
viable candidates to explain the primordial-intermediating-present epochs.
| [
{
"created": "Fri, 12 Jul 2024 17:18:04 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Jul 2024 08:57:04 GMT",
"version": "v2"
}
] | 2024-07-24 | [
[
"Kavya",
"N. S.",
""
],
[
"Mishra",
"Sai Swagat",
""
],
[
"Sahoo",
"P. K.",
""
],
[
"Venkatesha",
"V.",
""
]
] | The ability of Big Bang Nucleosynthesis theory to accurately predict the primordial abundances of helium and deuterium, as well as the baryon content of the Universe, is considered one of the most significant achievements in modern physics. In the present study, we consider two highly motivated hybrid $f(T)$ models and constrain them using the observations from the Big Bang Nucleosynthesis era. In addition, using late-time observations of Cosmic Chronometers and Gamma-Ray-Bursts, the ranges of the model parameters are confined which are in good agreement with early time bounds. Subsequently, the common ranges obtained from the analysis for early and late time are summarized. Further, we verify the intermediating epochs by investigating the profiles of cosmographic parameters using the model parameter values from the common range. From this study, we find the considered teleparallel models are viable candidates to explain the primordial-intermediating-present epochs. |
gr-qc/9912065 | Benjamin J. Owen | Benjamin J. Owen (Albert Einstein Institut) | Gravitational waves from the r-modes of rapidly rotating neutron stars | 10 pages, 2 figures, 3rd Edoardo Amaldi Conference on Gravitational
Waves | null | 10.1063/1.1291840 | AEI-1999-52 | gr-qc astro-ph | null | Since the last Amaldi meeting in 1997 we have learned that the r-modes of
rapidly rotating neutron stars are unstable to gravitational radiation reaction
in astrophysically realistic conditions. Newborn neutron stars rotating more
rapidly than about 100Hz may spin down to that frequency during up to one year
after the supernova that gives them birth, emitting gravitational waves which
might be detectable by the enhanced LIGO interferometers at a distance which
includes several supernovae per year. A cosmological background of these events
may be detectable by advanced LIGO. The spins (about 300Hz) of neutron stars in
low-mass x-ray binaries may also be due to the r-mode instability (under
different conditions), and some of these systems in our galaxy may also produce
detectable gravitational waves--see the review by G. Ushomirsky in this volume.
Much work is in progress on developing our understanding of r-mode astrophysics
to refine the early, optimistic estimates of the detectability of the
gravitational waves.
| [
{
"created": "Wed, 15 Dec 1999 16:45:40 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Owen",
"Benjamin J.",
"",
"Albert Einstein Institut"
]
] | Since the last Amaldi meeting in 1997 we have learned that the r-modes of rapidly rotating neutron stars are unstable to gravitational radiation reaction in astrophysically realistic conditions. Newborn neutron stars rotating more rapidly than about 100Hz may spin down to that frequency during up to one year after the supernova that gives them birth, emitting gravitational waves which might be detectable by the enhanced LIGO interferometers at a distance which includes several supernovae per year. A cosmological background of these events may be detectable by advanced LIGO. The spins (about 300Hz) of neutron stars in low-mass x-ray binaries may also be due to the r-mode instability (under different conditions), and some of these systems in our galaxy may also produce detectable gravitational waves--see the review by G. Ushomirsky in this volume. Much work is in progress on developing our understanding of r-mode astrophysics to refine the early, optimistic estimates of the detectability of the gravitational waves. |
1710.08630 | Xing-Hui Feng | Jincheng An, Jun Peng, Yan Liu, Xing-Hui Feng | Kerr-Sen Black Hole as Accelerator for Spinning Particles | Latex,17 pages,1 figure,minor revision,accepted by PRD | Phys. Rev. D 97, 024003 (2018) | 10.1103/PhysRevD.97.024003 | null | gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been proved that arbitrarily high-energy collision between two
particles can occur near the horizon of an extremal Kerr black hole as long as
the energy $E$ and angular momentum $L$ of one particle satisfies a critical
relation, which is called the BSW mechanism. Previous researchers mainly
concentrate on geodesic motion of particles. In this paper, we will take
spinning particle which won't move along a timelike geodesic into our
consideration, hence, another parameter $s$ describing the particle's spin
angular momentum was introduced. By employing the Mathisson-Papapetrou-Dixon
equation describing the movement of spinning particle, we will explore whether
a Kerr-Sen black hole which is slightly different from Kerr black hole can be
used to accelerate a spinning particle to arbitrarily high energy. We found
that when one of the two colliding particles satisfies a critical relation
between the energy $E$ and the total angular momentum $J$, or has a critical
spinning angular momentum $s_c$, a divergence of the center-of-mass energy
$E_{cm}$ will be obtained.
| [
{
"created": "Tue, 24 Oct 2017 07:27:26 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Oct 2017 05:39:35 GMT",
"version": "v2"
},
{
"created": "Wed, 29 Nov 2017 05:43:34 GMT",
"version": "v3"
}
] | 2018-01-10 | [
[
"An",
"Jincheng",
""
],
[
"Peng",
"Jun",
""
],
[
"Liu",
"Yan",
""
],
[
"Feng",
"Xing-Hui",
""
]
] | It has been proved that arbitrarily high-energy collision between two particles can occur near the horizon of an extremal Kerr black hole as long as the energy $E$ and angular momentum $L$ of one particle satisfies a critical relation, which is called the BSW mechanism. Previous researchers mainly concentrate on geodesic motion of particles. In this paper, we will take spinning particle which won't move along a timelike geodesic into our consideration, hence, another parameter $s$ describing the particle's spin angular momentum was introduced. By employing the Mathisson-Papapetrou-Dixon equation describing the movement of spinning particle, we will explore whether a Kerr-Sen black hole which is slightly different from Kerr black hole can be used to accelerate a spinning particle to arbitrarily high energy. We found that when one of the two colliding particles satisfies a critical relation between the energy $E$ and the total angular momentum $J$, or has a critical spinning angular momentum $s_c$, a divergence of the center-of-mass energy $E_{cm}$ will be obtained. |
1105.3069 | Kentaro Takami | Kentaro Takami, Luciano Rezzolla and Shin'ichirou Yoshida | A quasi-radial stability criterion for rotating relativistic stars | 5 pages, 4 figures; accepted to MNRAS Letters | Mon.Not.Roy.Astron.Soc.416:L1-L5,2011 | 10.1111/j.1745-3933.2011.01085.x | null | gr-qc astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The stability properties of relativistic stars against gravitational collapse
to black hole is a classical problem in general relativity. A sufficient
criterion for secular instability was established by Friedman, Ipser and Sorkin
(1988), who proved that a sequence of uniformly rotating barotropic stars is
secularly unstable on one side of a turning point and then argued that a
stronger result should hold: that the sequence should be stable on the opposite
side, with the turning point marking the onset of secular instability. We show
here that this expectation is not met. By computing in full general relativity
the $F$-mode frequency for a large number of rotating stars, we show that the
neutral-stability point, i.e., where the frequency becomes zero, differs from
the turning point for rotating stars. Using numerical simulations we validate
that the new criterion can be used to assess the dynamical stability of
relativistic rotating stars.
| [
{
"created": "Mon, 16 May 2011 11:34:10 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Jun 2011 13:35:36 GMT",
"version": "v2"
}
] | 2011-08-22 | [
[
"Takami",
"Kentaro",
""
],
[
"Rezzolla",
"Luciano",
""
],
[
"Yoshida",
"Shin'ichirou",
""
]
] | The stability properties of relativistic stars against gravitational collapse to black hole is a classical problem in general relativity. A sufficient criterion for secular instability was established by Friedman, Ipser and Sorkin (1988), who proved that a sequence of uniformly rotating barotropic stars is secularly unstable on one side of a turning point and then argued that a stronger result should hold: that the sequence should be stable on the opposite side, with the turning point marking the onset of secular instability. We show here that this expectation is not met. By computing in full general relativity the $F$-mode frequency for a large number of rotating stars, we show that the neutral-stability point, i.e., where the frequency becomes zero, differs from the turning point for rotating stars. Using numerical simulations we validate that the new criterion can be used to assess the dynamical stability of relativistic rotating stars. |
1503.08331 | Masashi Kimura | Mandar Patil, Pankaj S. Joshi, Ken-ichi Nakao, Masashi Kimura,
Tomohiro Harada | Timescale for trans-Planckian collisions in Kerr spacetime | 15 pages, v2: minor revisions, v3: minor revisions, to appear in EPL | null | 10.1209/0295-5075/110/30004 | OCU-PHYS-421, AP-GR-121, RUP-15-7 | gr-qc astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We make a critical comparison between ultra-high energy particle collisions
around an extremal Kerr black hole and that around an over-spinning Kerr
singularity, mainly focusing on the issue of the timescale of collisions. We
show that the time required for two massive particles with the proton mass or
two massless particles of GeV energies to collide around the Kerr black hole
with Planck energy is several orders of magnitude longer than the age of the
Universe for astro-physically relevant masses of black holes, whereas time
required in the over-spinning case is of the order of ten million years which
is much shorter than the age of the Universe. Thus from the point of view of
observation of Planck scale collisions, the over-spinning Kerr geometry,
subject to their occurrence, has distinct advantage over their black hole
counterparts.
| [
{
"created": "Sat, 28 Mar 2015 17:43:42 GMT",
"version": "v1"
},
{
"created": "Sun, 5 Apr 2015 14:41:57 GMT",
"version": "v2"
},
{
"created": "Fri, 15 May 2015 09:54:52 GMT",
"version": "v3"
}
] | 2015-06-11 | [
[
"Patil",
"Mandar",
""
],
[
"Joshi",
"Pankaj S.",
""
],
[
"Nakao",
"Ken-ichi",
""
],
[
"Kimura",
"Masashi",
""
],
[
"Harada",
"Tomohiro",
""
]
] | We make a critical comparison between ultra-high energy particle collisions around an extremal Kerr black hole and that around an over-spinning Kerr singularity, mainly focusing on the issue of the timescale of collisions. We show that the time required for two massive particles with the proton mass or two massless particles of GeV energies to collide around the Kerr black hole with Planck energy is several orders of magnitude longer than the age of the Universe for astro-physically relevant masses of black holes, whereas time required in the over-spinning case is of the order of ten million years which is much shorter than the age of the Universe. Thus from the point of view of observation of Planck scale collisions, the over-spinning Kerr geometry, subject to their occurrence, has distinct advantage over their black hole counterparts. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.