Results 31 to 40 of about 537,661 (283)
Non-linear Evolution of Matter Power Spectrum in Modified Theory of Gravity [PDF]
, 2009 We present a formalism to calculate the non-linear matter power spectrum in modified gravity models that explain the late-time acceleration of the Universe without dark energy.
Atsushi Taruya +5 more
core +3 more sources
Editorial to the Special Issue “Probing New Physics with Black Holes”
Universe, 2020 Black holes are fantastic laboratories for probing new physics. Both theoretically and experimentally, many new ideas are emerging to use them as tools for understanding better quantum gravity or classical gravity beyond general relativity.
Aurélien Barrau
doaj +1 more source
International Journal of Modern Physics D, 2008 We describe how a certain simple modification of general relativity, in which the local cosmological constant is allowed to depend on the space–time curvature, predicts the existence of halos of modified gravity surrounding spherically symmetric objects. We show that the gravitational mass of an object weighed together with its halo can be much larger
Krasnov, Kirill, Shtanov, Yuri
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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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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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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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