Results 21 to 30 of about 632,753 (317)
Hyperbolicity in spherical gravitational collapse in a Horndeski theory [PDF]
Physical Review D, 2019 We numerically study spherical gravitational collapse in shift symmetric Einstein dilaton Gauss Bonnet (EdGB) gravity. We find evidence that there are open sets of initial data for which the character of the system of equations changes from hyperbolic to
Justin L. Ripley, F. Pretorius
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Gravitational quantum collapse in dilute systems
Comptes Rendus. Physique, 2022 Penrose has suggested that large fluctuations of the gravitational energy of quantum systems, resulting from fluctuations of its density in space, may induce a quantum collapse mechanism [1], but he did not propose a precise dynamics for this process. We
Laloë, Franck
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SPHERICALLY SYMMETRIC GRAVITATIONAL COLLAPSE [PDF]
Modern Physics Letters A, 2009 In this paper, we discuss gravitational collapse of spherically symmetric spacetimes. We derive a general formalism by taking two arbitrary spherically symmetric spacetimes with g00 = 1. Israel's junction conditions are used to develop this formalism. The formulas for extrinsic curvature tensor are obtained.
Sharif, M., Iqbal, Khadija
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Gravitational collapse: expanding and collapsing regions [PDF]
General Relativity and Gravitation, 2010 12 pages, 4 figures, accepted for publication in Gen.
Sharif, M., Abbas, G.
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PLANE SYMMETRIC GRAVITATIONAL COLLAPSE [PDF]
International Journal of Modern Physics A, 2008 In this paper, we derive the general formulation by considering two arbitrary plane symmetric space–times using Israel's method. As an example, we apply this formulation to known plane symmetric space–times. We take the Taub's static metric in the interior region whereas Kasner's nonstatic metric in the exterior region.
Sharif, M., Ahmad, Zahid
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Evidence for the formation of comet 67P/Churyumov-Gerasimenko through gravitational collapse of a bound clump of pebbles [PDF]
, 2017 The processes that led to the formation of the planetary bodies in the Solar system are still not fully understood. Using the results obtained with the comprehensive suite of instruments onboard the European Space Agency's Rosetta mission, we present ...
J. Blum +21 more
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The nature of the naked singularity in generalized Vaidya spacetime and white hole geodesics
Physics of Complex Systems, 2021 This paper gives conditions to the energy-momentum tensor when the gravitational collapse of generalized Vaidya spacetime results in a naked singularity.
Виталий Дмитриевич Вертоградов
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Gravitational collapse in General Relativity and in R2-gravity: A comparative study [PDF]
International Journal of Geometric Methods in Modern Physics (IJGMMP), 2018 We compare the gravitational collapse of homogeneous perfect fluid with various equations of state in the framework of General Relativity and in [Formula: see text] gravity. We make our calculations using dimensionless time with characteristic timescale [
A. Astashenok +3 more
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Gravitational Wave Speed: Undefined. Experiments Proposed [PDF]
Research Ideas and Outcomes, 2018 Since changes in all 4 dimensions of spacetime are components of displacement for gravitational waves, a theoretical result is presented that their speed is undefined, and that the Theory of Relativity is not reliable to predict their speed ...
Daniel Russell
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Gravitational collapse of the OMC-1 region [PDF]
, 2017 We have investigated the global dynamical state of the integral shaped filament in the Orion A cloud using new N 2 H + (1−0) large-scale, IRAM 30 m observations.
Á. Hacar +4 more
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