Results 41 to 50 of about 69,354 (164)
Matter Instability in Theories with Modified Induced Gravity
Advances in High Energy Physics, 2012 Matter stability is a necessary condition to have a cosmologically viable model. Modified gravity in the spirit of f(R) theories suffers from matter instability in some subdomains of the model parameter space.
Kourosh Nozari, Faeze Kiani
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Generalized gravity from modified DFT
Journal of High Energy Physics, 2017 Recently, generalized equations of type IIB supergravity have been derived from the requirement of classical kappa-symmetry of type IIB superstring theory in the Green-Schwarz formulation.
Yuho Sakatani +2 more
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Probing the existence of the ZTF Casimir wormholes in the framework of f(R) gravity
Nuclear Physics B, 2022 For the spherically symmetric static traversable wormholes, supported by the Casimir energy in f(R)=R+αR2 Quadratic, f(R)=f0Rn power-law Modified Gravity (MOG) theories we investigate energy conditions and dynamical stability of the wormhole solutions ...
Oleksii Sokoliuk +2 more
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Formalizing anisotropic inflation in modified gravity
Nuclear Physics B, 2022 Motivated by the fact that the pre-inflationary era may evolve in an exotic way, in this work we formalize anisotropic evolution in the context of modified gravity, focusing on pre-inflationary and near the vicinity of the inflationary epochs.
S. Nojiri +3 more
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Modified gravity one-loop partition function
European Physical Journal C: Particles and Fields, 2018 The one-loop partition function of the $$f(R,R_{\mu \nu }R^{\mu \nu })$$ f(R,RμνRμν) gravity theory is obtained around $$\hbox {AdS}_4$$ AdS4 background.
Shahab Shahidi +3 more
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Charting the landscape of modified gravity [PDF]
Journal of High Energy Physics, 2007 We explore brane induced gravity on a 3-brane in six locally flat dimensions. To regulate the short distance singularities in the brane core, we resolve the thin brane by a cylindrical 4-brane, with the geometry of 4D Minkowski $\times$ a circle, which has an axion flux to cancel the vacuum pressure in the compact direction.
Kaloper, Nemanja, Kiley, Derrick
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Classical and Quantum GravityAbstract A complete canonical formulation of general covariance makes it possible to construct new modified theories of gravity that are not of higher-curvature form, as shown here in a spherically symmetric setting. The usual uniqueness theorems are evaded by using a crucial and novel ingredient, allowing for fundamental fields of ...
Martin Bojowald, Erick I Duque
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Gravitational baryogenesis in f(T, Lm) gravity
Nuclear Physics BThe observed matter–antimatter asymmetry of the Universe remains a fundamental challenge in modern physics. In this work, we explore gravitational baryogenesis within the framework of f(T, Lm) gravity, where the gravitational Lagrangian depends on both ...
Daniel F P Cruz +2 more
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Entropy, 2012 Along this review, we focus on the study of several properties of modified gravity theories, in particular on black-hole solutions and its comparison with those solutions in General Relativity, and on Friedmann–Lemaˆıtre–Robertson–Walker metrics.
Diego Sáez-Gómez +1 more
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General Relativity solutions in modified gravity
Physics Letters B, 2018 Recent gravitational wave observations of binary black hole mergers and a binary neutron star merger by LIGO and Virgo Collaborations associated with its optical counterpart constrain deviation from General Relativity (GR) both on strong-field regime and
Hayato Motohashi, Masato Minamitsuji
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