Results 11 to 20 of about 62,947 (343)
Effects of a Late Gravitational Transition on Gravitational Waves and Anticipated Constraints
Universe, 2023 We investigate the evolution of gravitational waves through discontinuous evolution (transition) of the Hubble expansion rate H(z) at a sudden cosmological singularity, which may be due to a transition of the value of the gravitational constant.
Evangelos Achilleas Paraskevas +1 more
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Causal structure of singularity in non-spherical gravitational collapse
European Physical Journal C: Particles and Fields, 2022 We investigate here the final state of gravitational collapse of a non-spherical and non-marginally bound dust cloud as modeled by the Szekeres spacetime.
Dipanjan Dey +3 more
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Singular Monopoles and Gravitational Instantons [PDF]
Communications in Mathematical Physics, 1999 We model A_k and D_k asymptotically locally flat gravitational instantons on the moduli spaces of solutions of U(2) Bogomolny equations with prescribed singularities. We study these moduli spaces using Ward correspondence and find their twistor description.
Cherkis, Sergey A., Kapustin, Anton
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Quantum dynamics corresponding to the chaotic BKL scenario
European Physical Journal C: Particles and Fields, 2023 We quantize the solution to the Belinski– Khalatnikov–Lifshitz (BKL) scenario using the integral quantization method. Quantization smears the gravitational singularity, preventing its localization in the configuration space.
Andrzej Góźdź +2 more
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Gravitational field of slightly deformed naked singularities
European Physical Journal C: Particles and Fields, 2022 We derive a particular approximate solution of Einstein equations, describing the gravitational field of a mass distribution that slightly deviates from spherical symmetry. The deviation is described by means of a quadrupole parameter that is responsible
Saken Toktarbay +3 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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Cosmology from Newton–Chern–Simons gravity
Nuclear Physics B, 2020 We study a five-dimensional non-relativistic gravity theory whose action is composed of a gravitational sector and a sector of matter where the gravitational sector is given by the so called Newton–Chern–Simons gravity and where the matter sector is ...
S. Lepe, G. Rubio, P. Salgado
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A bouncing cosmology from VECROs
European Physical Journal C: Particles and Fields, 2023 We argue that, in the same way that in a black hole space-time VECROs will form in order to cancel the gravitational effects of a collapsing mass shell and prevent the formation of a singularity, in a contracting universe a gas of VECROs will form to ...
Robert Brandenberger +1 more
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Gravitationally collapsing stars in f(R) gravity
European Physical Journal C: Particles and Fields, 2021 The gravitational dynamics of a collapsing matter configuration which is simultaneously radiating heat flux is studied in f(R) gravity. Three particular functional forms in f(R) gravity are considered to show that it is possible to envisage boundary ...
Suresh C. Jaryal, Ayan Chatterjee
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Averaged energy conditions for vector fields
Physics Letters B, 2023 In this work we shall obtain sufficient conditions for the appearance of singularities in gravitational theories which propagate an extra vector degree of freedom, based on the known relaxations of the singularity theorems.
Francisco José Maldonado Torralba
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