Results 1 to 10 of about 167,327,776 (267)
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
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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
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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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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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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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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-metric geometry as the origin of mass in gauge theories of scale invariance
European Physical Journal C: Particles and Fields, 2023 We discuss gauge theories of scale invariance beyond the Standard Model (SM) and Einstein gravity. A consequence of gauging this symmetry is that their underlying 4D geometry is non-metric ( $$\nabla _\mu g_{\alpha \beta }\!\not =\!0$$ ∇ μ g α β ≠ 0 ...
D. M. Ghilencea
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Universally finite gravitational and gauge theories
Nuclear Physics B, 2015 It is well known that standard gauge theories are renormalizable in D=4 while Einstein gravity is renormalizable in D=2. This is where the research in the field of two derivatives theories is currently standing.
Leonardo Modesto, Lesław Rachwał
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Gravitational Waves: The Theorist’s Swiss Knife
Universe, 2022 Gravitational waves provide a novel and powerful way to test astrophysical models of compact objects, early universe processes, beyond the Standard Model particle physics, dark matter candidates, Einstein’s theory of General Relativity and extended ...
Mairi Sakellariadou
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