Results 11 to 20 of about 167,327,776 (267)
The viability of modified gravity theories [PDF]
, 2009 PhDThis thesis studies the viability of classes of modified gravity (MG) theories based on generalisations of the Einstein-Hilbert action. Particular emphasis is given to f(R) theories in both the metric and Palatini formalisms, scalar-tensor theories ...
Uddin, Kotub
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PhD thesis : Compact objects in modified theories of gravity [PDF]
, 2022 The formulation of General Relativity by Albert Einstein in 1915 revolutionised our understanding of the gravitational interaction. However, despite its tremendous successes, this theory struggle to explain certain important phenomena such as the ...
Ducobu, Ludovic
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Gravitational quasinormal modes of black holes in Einstein-aether theory
Nuclear Physics B, 2019 The local Lorentz violation (LV) in gravity sector should show itself in derivation of the characteristic quasinormal modes (QNMs) of black hole mergers from their general relativity case.
Chikun Ding
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Analytical amplitudes from numerical solutions of the scattering equations
Journal of High Energy Physics, 2020 The CHY formalism for massless scattering provides a cohesive framework for the computation of scattering amplitudes in a variety of theories. It is especially compelling because it elucidates existing relations among theories which are seemingly ...
Giuseppe De Laurentis
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Scaling solution for field-dependent gauge couplings in quantum gravity
Nuclear Physics B, 2022 Quantum gravity can determine the dependence of gauge couplings in a scalar field, which is related to possible fifth forces and time varying fundamental “constants”. This prediction is based on the scaling solution of functional flow equations.
C. Wetterich
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Looking for Traces of Nonminimally Coupled Dark Matter in the X-COP Galaxy Clusters Sample
The Astrophysical Journal, 2023 We look for possible evidence of a nonminimal coupling (NMC) between dark matter (DM) and gravity using data from the X-COP compilation of galaxy clusters.
Giovanni Gandolfi +3 more
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, 2010 The observable universe could be a 1+3-surface (the “brane”) embedded in a 1+3+d-dimensional spacetime (the “bulk”), with Standard Model particles and fields trapped on the brane while gravity is free to access the bulk.
Roy Maartens +3 more
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Strong Lensing Systems as Probes of Dark Energy Models and Non-Standard Theories of Gravity [PDF]
, 2011 Gravitational lensing is a consequence of light deflection in gravitational field. Starlight deflection by the Sun, measured as 1′′.7 at the solar limb was the first evidence in favor of General Relativity. This result is often presented in contrast with so called Newtonian prediction dated back to Soldner, but in fact it announces much more by its ...
openaire +1 more source
Friction in gravitational waves: A test for early-time modified gravity
Physics Letters B, 2015 Modified gravity theories predict in general a non-standard equation for the propagation of gravitational waves. Here we discuss the impact of modified friction and speed of tensor modes on cosmic microwave polarization B modes.
Valeria Pettorino, Luca Amendola
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Spacetime and the Philosophical Challenge of Quantum Gravity [PDF]
, 2001 We survey some philosophical aspects of the search for a quantum theory of gravity, emphasising how quantum gravity throws into doubt the treatment of spacetime common to the two `ingredient theories' (quantum theory and general relativity), as a 4 ...
Butterfield, Jeremy +3 more
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