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Cosmological effects on f(R̄,T̄) gravity through a non-standard theory
International Journal of Modern Physics D, 2022 This study aims to investigate the impact of dark energy in cosmological scenarios by exploiting [Formula: see text] gravity within the framework of a nonstandard theory, called K-essence theory, where [Formula: see text] represents the Ricci scalar and [Formula: see text] denotes the trace of the energy–momentum tensor associated with the K-essence ...
Arijit Panda +4 more
openaire +3 more sources
Dark Matter in Fractional Gravity. I. Astrophysical Tests on Galactic Scales
The Astrophysical Journal, 2023 We explore the possibility that the dark matter (DM) component in galaxies may originate fractional gravity. In such a framework, the standard law of inertia continues to hold, but the gravitational potential associated with a given DM density ...
Francesco Benetti +4 more
doaj +1 more source
Khronometric Theories of Modified Newtonian Dynamics
The Astrophysical Journal, 2023 In 2011 Blanchet and Marsat suggested a fully relativistic version of Milgrom's modified Newtonian dynamics in which the dynamical degrees of freedom consist of the spacetime metric and a foliation of spacetime, the khronon field.
Éanna. É. Flanagan
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Void Lensing in Cubic Galileon Gravity
The Astrophysical Journal, 2023 Weak-lensing studies via cosmic voids are a promising probe of modified gravity (MG). The excess surface mass density (ESD) is widely used as a lensing statistic in weak-lensing research.
Chen Su +8 more
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String Theory, Loop Quantum Gravity and Eternalism [PDF]
, 2020 Eternalism, the view that what we regard locally as being located in the past, the present and the future equally exists, is the best ontological account of temporal existence in line with special and general relativity.
Le Bihan, Baptiste
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Geodesic Incompleteness and Partially Covariant Gravity
Universe, 2021 We study the issue of length renormalization in the context of fully covariant gravity theories as well as non-relativistic ones such as Hořava–Lifshitz gravity.
Ignatios Antoniadis, Spiros Cotsakis
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Tidal Deformability of Neutron Stars in Scalar-tensor Theories of Gravity
The Astrophysical Journal, 2023 Gravitational waves from compact binary coalescences are valuable for testing theories of gravity in the strong field regime. By measuring neutron star tidal deformability using gravitational waves from binary neutron stars, stringent constraints were ...
Stephanie M. Brown
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The Astrophysical Journal, 2023 A gravitational anomaly is found at weak gravitational acceleration g _N ≲ 10 ^−9 m s ^−2 from analyses of the dynamics of wide binary stars selected from the Gaia DR3 database that have accurate distances, proper motions, and reliably inferred stellar ...
Kyu-Hyun Chae
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Non-singular modified gravity: the unification of the inflation, dark energy and dark mater [PDF]
, 2009 Using the fluid representation, we formulate the conditions for the appearance of all four types finite-time future singularity in modified gravity in accelerating FRW universe.
Nojiri, Shin'ichi, Odintsov, Sergei D.
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ISIS: a new N-body cosmological code with scalar fields based on RAMSES. Code presentation and application to the shapes of clusters [PDF]
, 2014 Several extensions of the standard cosmological model include scalar fields as new degrees of freedom in the underlying gravitational theory. A particular class of these scalar field theories include screening mechanisms intended to hide the scalar field
Llinares, Claudio +2 more
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