Results 11 to 20 of about 11,605 (193)
Anisotropic evolution of 5D Friedmann-Robertson-Walker spacetime [PDF]
Physical Review D, 2011 We examine the time evolution of the five-dimensional Einstein field equations subjected to a flat, anisotropic Robertson-Walker metric, where the 3D and higher-dimensional scale factors are allowed to dynamically evolve at different rates. By adopting equations of state relating the 3D and higher-dimensional pressures to the density, we obtain an ...
Middleton, Chad A., Stanley, Ethan
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Effective lagrangian for a mass dimension one fermionic field in curved spacetime [PDF]
Journal of High Energy Physics, 2018 In this work we use momentum-space techniques to evaluate the propagator G(x, x ′) for a spin 1/2 mass dimension one spinor field on a curved Friedmann-Robertson-Walker spacetime.
R.J. Bueno Rogerio +3 more
doaj +7 more sources
WITHDRAWN: Local causality in a Friedmann–Robertson–Walker spacetime [PDF]
Annals of Physics, 2016 A local, deterministic, and realistic model within a Friedmann-Robertson-Walker spacetime with constant spatial curvature (S^3) is presented which describes simultaneous measurements of the spins of two fermions emerging in a singlet state from the decay
Christian, Joy
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Toroidal marginally outer trapped surfaces in closed Friedmann-Lemaitre-Robertson-Walker spacetimes: Stability and isoperimetric inequalities [PDF]
, 1920 We investigate toroidal Marginally Outer Trapped Surfaces (MOTS) and Marginally Outer Trapped Tubes (MOTT) in closed Friedmann-Lemaitre-Robertson-Walker (FLRW) geometries. They are constructed by embedding Constant Mean Curvature (CMC) Clifford tori in a
Mach, Patryk, Xie, Naqing
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Assisted inflation in Friedmann-Robertson-Walker and Bianchi spacetimes [PDF]
Physical Review D, 2000 We use exact general solutions for the spatially flat FRW and the anisotropic Bianchi I cosmologies to show that generically uncoupled scalar fields cooperate to make inflation more probable, while the presence of several interacting fields hinders the occurrence of the phenomenon, in accordance with previous results based on particular power-law ...
Chimento, Luis Pascual +3 more
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Scalar Field Evolution at Background and Perturbation Levels for a Broad Class of Potentials
Fortschritte der Physik, Volume 71, Issue 10-11, November 2023., 2023 Abstract In this paper, a non‐interacting scalar field cosmology with an arbitrary potential using the f‐deviser method that relies on the differentiability properties of the potential is investigated. Using this alternative mathematical approach, a unified dynamical system analysis at a scalar field's background and perturbation levels with arbitrary ...
Genly Leon +5 more
wiley +1 more source
Stress-energy tensor of adiabatic vacuum in Friedmann-Robertson-Walker spacetimes [PDF]
Journal of Cosmology and Astroparticle Physics, 2011 We compute the leading order contribution to the stress-energy tensor corresponding to the modes of a quantum scalar field propagating in a Friedmann-Robertson-Walker universe with arbitrary coupling to the scalar curvature, whose exact mode functions can be expanded as an infinite adiabatic series.
Kaya, Ali, Tarman, Merve
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Dynamical Analysis in Chameleon Dark Energy
Fortschritte der Physik, Volume 71, Issue 8-9, September 2023., 2023 Abstract A detailed analysis of the phase‐space for the field equations in scalar field cosmology with a chameleon cosmology in a spatially flat Friedmann–Lemaître–Robertson–Walker spacetime is presented. For the matter source it is assumed that it is an ideal gas with a constant equation of state parameter, while for the scalar field potential and the
Andronikos Paliathanasis
wiley +1 more source
f(T,B) gravity in a Friedmann–Lemaître–Robertson–Walker universe with nonzero spatial curvature
Mathematical Methods in the Applied Sciences, Volume 46, Issue 4, Page 3905-3922, 15 March 2023., 2023 We investigate exact solutions and the asymptotic dynamics for the Friedmann–Lemaître–Robertson–Walker universe with nonzero spatial curvature in the fourth‐order modified teleparallel gravitational theory known as f(T,B)$$ f\left(T,B\right) $$ theory. We show that the field equations admit a minisuperspace description, and they can reproduce any exact
Andronikos Paliathanasis, Genly Leon
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Advances in High Energy Physics, Volume 2023, Issue 1, 2023., 2023 In this paper, using the Hamilton‐Jacobi method, we discuss the tunnelling of fermions when the dual influence of quantum gravity and the deformation of a parameterized black hole are taken into account. With the influence of the generalized uncertainty principle, there exists an offset around the standard Hawking temperature.
Zhonghua Li, Mariana Frank
wiley +1 more source