Results 11 to 20 of about 3,864,648 (162)
Constraints on modified gravity from the BOSS galaxy survey [PDF]
Journal of Cosmology and Astroparticle Physics, 2022 We develop a pipeline to set new constraints on scale-independent modified gravity, from the galaxy power spectrum in redshift space of BOSS DR12. The latter is modelled using the effective field theory of large-scale structure up to 1-loop order in ...
L. Piga +5 more
semanticscholar +1 more source
Cosmological dynamical systems in modified gravity [PDF]
The European Physical Journal C, 2022 The field equations of modified gravity theories, when considering a homogeneous and isotropic cosmological model, always become autonomous differential equations. This relies on the fact that in such models all variables only depend on cosmological time,
C. Böhmer, Erik Jensko, R. Lazkoz
semanticscholar +1 more source
A new approach and code for spinning black holes in modified gravity [PDF]
Classical and quantum gravity, 2022 We discuss and implement a spectral method approach to computing stationary and axisymmetric black hole solutions and their properties in modified theories of gravity.
Pedro G. S. Fernandes, D. Mulryne
semanticscholar +1 more source
On the Conformal Frames in f(R) Gravity
Universe, 2022 We discuss gravitational physics in the Jordan and Einstein frames of f(R) gravity coupled to the Standard Model. We elucidate the way in which the observed gravitational coupling arises in the Einstein frame for generic f(R).
Yuri Shtanov
doaj +1 more source
Modified gravity: A unified approach [PDF]
Physical Review D, 2021 Starting from the original Einstein action, sometimes called the Gamma squared action, we propose a new setup to formulate modified theories of gravity.
C. Böhmer, Erik Jensko
semanticscholar +1 more source
Big Bang Nucleosynthesis Constraints on f (T, TG) Gravity
Universe, 2022 We confront f(T,TG) gravity, with big bang nucleosynthesis (BBN) requirements. The former is obtained using both the torsion scalar, as well as the teleparallel equivalent of the Gauss–Bonnet term, in the Lagrangian, resulting to modified Friedmann ...
Petros Asimakis +3 more
doaj +1 more source
Mathematics, 2023 In this work, it is shown that the geometry of a gravity field generated by a spheroid with low eccentricity can be described with the help of a newly modified Helmholtz equation.
Gerassimos Manoussakis
doaj +1 more source
Universe, 2022 Scalar Tensor Vector Gravity (STVG) or MOdified Gravity (MOG) is a metric theory of gravity with dynamical scalar fields and a massive vector field introduced in addition to the metric tensor.
Sreekanth Harikumar
doaj +1 more source
Probing modified gravity theories with multiple measurements of high-redshift quasars [PDF]
, 2021 In this paper, we quantify the ability of multiple measurements of high-redshift quasars (QSOs) to constrain several theories of modified gravity, including the DvaliGabadadze-Porrati braneworld scenario, generalized Chaplygin gas, f(T ) modified gravity,
Yujie Lian +5 more
semanticscholar +1 more source
Black hole perturbations in modified gravity [PDF]
Physical Review D, 2021 We study the linear perturbations about nonrotating black holes in the context of degenerate higher-order scalar-tensor (DHOST) theories, using a systematic approach that extracts the asymptotic behaviour of perturbations (at spatial infinity and near ...
D. Langlois, K. Noui, Hugo Roussille
semanticscholar +1 more source