Results 21 to 30 of about 670,040 (334)
On Mass Spectra of Primordial Black Holes
Frontiers in Astronomy and Space Sciences, 2021 Evidence for the primordial black holes (PBH) presence in the early Universe renews permanently. New limits on their mass spectrum challenge existing models of PBH formation.
Alexander A. Kirillov +2 more
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Long-Range Scalar Forces in Five-Dimensional General Relativity
Advances in Mathematical Physics, 2020 We present new results regarding the long-range scalar field that emerges from the classical Kaluza unification of general relativity and electromagnetism.
L. L. Williams
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Universe, 2023 We discuss the problem of the quantization and dynamic evolution of a scalar free field in the interior of a Schwarzschild black hole. A unitary approach to the dynamics of the quantized field is proposed: a time-dependent Hamiltonian governing the ...
Pawel Gusin +5 more
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Journal of Mathematical Physics, 1996 Static spherically symmetric uncoupled scalar space–times have no event horizon and a divergent Kretschmann singularity at the origin of the coordinates. The singularity is always present so that nonstatic solutions have been sought to see if the singularities can develop from an initially singular free space–time.
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European Physical Journal C: Particles and Fields, 2018 With a suitable decomposition of its energy-momentum tensor into pressureless matter and a vacuum type term, we investigate the spherical gravitational collapse of a minimally coupled, self-interacting scalar field, showing that it collapses to a ...
S. Carneiro, J. C. Fabris
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Tachyons, scalar fields, and cosmology [PDF]
Physical Review D, 2004 We study the role that tachyon fields may play in cosmology as compared to the well-established use of minimally coupled scalar fields. We first elaborate on a kind of correspondence existing between tachyons and minimally coupled scalar fields; corresponding theories give rise to the same cosmological evolution for a particular choice of the initial ...
V. Gorini +3 more
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Renormalization for a Scalar Field in an External Scalar Potential [PDF]
Symmetry, 2018 The Pauli–Villars regularization procedure confirms and sharpens the conclusions reached previously by covariant point splitting. The divergences in the stress tensor of a quantized scalar field interacting with a static scalar potential are isolated into a three-parameter local, covariant functional of the background potential.
Stephen Fulling +2 more
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Analytic solutions in Einstein-aether scalar field cosmology
European Physical Journal C: Particles and Fields, 2020 In the context of Einstein-aether scalar field cosmology we solve the field equations and determine exact and analytic solutions. In particular, we consider a model proposed by Kanno and Soda where the aether and the scalar fields interact through the ...
Andronikos Paliathanasis, Genly Leon
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Vacuum Radiation from Massive Scalar Field
Universe, 2022 The vacuum radiation of a massive scalar field is studied by means of a single moving mirror. The field equation with an arbitrary-shaped mirror moving in (d+1) dimensions is given perturbatively in the non-relativistic limit.
Yu-Song Cao
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Shadow Images of a Rotating Dyonic Black Hole with a Global Monopole Surrounded by Perfect Fluid
Universe, 2020 In this paper, we revisit the rotating global monopole metric and extend the metric to a rotating dyonic global monopole in the presence of a perfect fluid. We then show that the surface topology at the event horizon, related to the metric computed, is a
Sumarna Haroon +2 more
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