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Cosmological hints of modified gravity?
Physical Review D, 2016 The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $Λ$CDM cosmological model. However interesting hints of slight deviations from $Λ$CDM have been found, including a $95 \%$ c.l. preference for a "modified gravity" structure formation
DI VALENTINO, ELEONORA +2 more
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Dark energy and modified gravity [PDF]
, 2010 Explanations of the late-time cosmic acceleration within the framework of general relativity are plagued by difficulties. General relativistic models are mostly based on a dark energy field with fine-tuned, unnatural properties. There is a great variety of models, but all share one feature in common -- an inability to account for the gravitational ...
Durrer, Ruth, Maartens, Roy
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A viable model for modified gravity [PDF]
Astrophysics and Space Science, 2014 We propose a model for modified gravity that meets the conditions of viability. The model has stable constant curvature solution and for an special case contains flat space time solution. The model also leads to matter stability under small perturbations of scalar curvature.
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Irreversible Geometrothermodynamics of Open Systems in Modified Gravity. [PDF]
Entropy (Basel), 2023 Pinto MAS, Harko T, Lobo FSN.
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A Comprehensive Analysis of Hyperbolical Fluids in Modified Gravity. [PDF]
Entropy (Basel), 2022 Yousaf Z, Bhatti MZ, Khlopov M, Asad H.
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COSMIC ACCELERATION AND MODIFIED GRAVITY
International Journal of Modern Physics D, 2007 I briefly discuss some attempts to construct a consistent modification to general relativity (GR) that might explain the observed late-time acceleration of the Universe and provide an alternative to dark energy. I describe the issues facing extensions to GR, illustrate these with a specific example, and discuss the resulting observational and ...
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Stellar oscillations in modified gravity [PDF]
Physical Review D, 2013 Starting from the equations of modified gravity hydrodynamics, we derive the equ tions of motion governing linear, adiabatic, radial perturbations of stars in scalar-tensor theories. There are two new features: first, the eigenvalue equation for the period of stellar oscillations is modified such that the eigenfrequencies are always larger than ...
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Modified entropy from action principle
Physics Letters BWe propose a modified gravity theory by extending the Einstein-Hilbert action with an arbitrary function of the Ricci scalar and the Kretschmann scalar invariants.
A. Dehyadegari, A. Sheykhi
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Pure-Connection Gravity and Anisotropic Singularities
Universe, 2018 In four space-time dimensions, there exists a special infinite-parameter family of chiral modified gravity theories. They are most properly described by a connection field, with space-time metric being a secondary and derived concept.
Kirill Krasnov, Yuri Shtanov
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Nuclear Physics BThis study explores wormhole solutions within two distinct modified gravity theories, namely f(R,T) gravity and f(Q,T) gravity, incorporating Bose-Einstein condensate (BEC) dark matter to analyze their geometric properties.
Chaitra Chooda Chalavadi +2 more
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