Results 21 to 30 of about 69,028 (315)
Journal of High Energy Physics, 2023 The quantum tunneling of charged massive vector boson particles across the event horizon of Kerr-Newman-de Sitter black hole is investigated under the influence of quantum gravity effects.
Yenshembam Priyobarta Singh +1 more
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Exact rotating black hole solutions for f(R) gravity by modified Newman Janis algorithm
European Physical Journal C: Particles and Fields, 2023 We show that the f(R)-gravity theories with constant Ricci scalar in the Jordan/Einstein frame can be described by Einstein or Einstein–Maxwell gravity with a cosmological term and a modified gravitational constant.
Pankaj Chaturvedi +3 more
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Constraining f(T,T) gravity with gravitational baryogenesis
Physics Letters B, 2023 Gravitational baryogenesis is one of the mechanisms which help us to explore more about our early universe, especially baryon-anti-baryon asymmetry.
Sai Swagat Mishra +2 more
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THERMODYNAMICS IN MODIFIED GRAVITY THEORIES [PDF]
International Journal of Modern Physics D, 2011 We demonstrate that there exists an equilibrium description of thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density f(R,ϕ,X), where R is the Ricci scalar and X is the kinetic energy of a scalar field ϕ.
Bamba, Kazuharu +2 more
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Reissner–Nordström Anti-de Sitter Black Holes in Mimetic F(R) Gravity
Universe, 2016 In this paper, we study under which conditions the Reissner–Nordström anti-de Sitter black hole can be a solution of the vacuum mimetic F ( R ) gravity with Lagrange multiplier and mimetic scalar potential.
V. K. Oikonomou
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The P-V phase transition of the FRW universe
European Physical Journal C: Particles and Fields, 2022 We define thermodynamic pressure P by work density W as the conjugate quantity of thermodynamic volume V from field equation. We derive the equations of state P=P(V, T) for the Friedmann–Robertson–Walker (FRW) universe in Einstein gravity and a modified ...
Shi-Bei Kong +4 more
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Modified gravity: A unified approach [PDF]
Physical Review D, 2021 Starting from the original Einstein action, sometimes called the Gamma squared action, we propose a new setup to formulate modified theories of gravity. This can yield a theory with second order field equations similar to those found in other popular modified gravity models. Using a more general setting the theory gives fourth order equations.
Christian G. Böhmer, Erik Jensko
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Rastall gravity is equivalent to Einstein gravity
Physics Letters B, 2018 Rastall gravity, originally developed in 1972, is currently undergoing a significant surge in popularity. Rastall gravity purports to be a modified theory of gravity, with a non-conserved stress–energy tensor, and an unusual non-minimal coupling between ...
Matt Visser
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Chaos in a Magnetized Modified Gravity Schwarzschild Spacetime
Universe, 2022 Based on the scalar–tensor–vector modified gravitational theory, a modified gravity Schwarzschild black hole solution has been given in the existing literature.
Daqi Yang +5 more
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Viscosity in Modified Gravity [PDF]
Entropy, 2012 A bulk viscosity is introduced in the formalism of modified gravity. It is shownthat, based on a natural scaling law for the viscosity, a simple solution can be found forquantities such as the Hubble parameter and the energy density. These solutions mayincorporate a viscosity-induced Big Rip singularity.
openaire +4 more sources