Results 41 to 50 of about 2,908,412 (339)
Scattering amplitudes in affine gravity [PDF]
Phys. Rev. D 103, 105019 (2021), 2020 Affine gravity is a connection-based formulation of gravity that does not involve a metric. After a review of basic properties of affine gravity, we compute the tree-level scattering amplitude of scalar particles interacting gravitationally via the connection in a curved spacetime.
arxiv +1 more source
Unimodular gravity vs general relativity: a status report [PDF]
Classical and quantum gravity, 2022 Unimodular gravity (UG) is an alternative to general relativity (GR) which, however, is so closely related to the latter that one can wonder to what extent they are different.
R. Carballo-Rubio +2 more
semanticscholar +1 more source
Journal of High Energy Physics, 2023 It has recently been argued that half degrees of freedom could emerge in Lorentz and parity invariant field theories, using a non-linear Proca field theory dubbed Proca-Nuevo as a specific example.
Claudia de Rham +4 more
doaj +1 more source
On the viability of f(Q) gravity models [PDF]
Classical and quantum gravity, 2022 In general relativity, the contracted Bianchi identity makes the field equation compatible with the energy conservation, likewise in f(R) theories of gravity.
Avik De, T. Loo
semanticscholar +1 more source
Superluminality in DHOST theory with extra scalar
Journal of High Energy Physics, 2021 We consider DHOST Ia theory interacting gravitationally with an additional conventional scalar field minimally coupled to gravity. At the linearized level of perturbations about cosmological background, we find that in the presence of a slowly rolling ...
S. Mironov, V. Rubakov, V. Volkova
doaj +1 more source
Gravity entanglement, quantum reference systems, degrees of freedom [PDF]
Classical and quantum gravity, 2022 Gravity mediated entanglement (GME) has been proposed as the first experimentally testable signature of quantum gravity. However, to what extent the effect is due to quantum gravity is under debate.
Marios Christodoulou +3 more
semanticscholar +1 more source
Massive spin-2 scattering and asymptotic superluminality
Journal of High Energy Physics, 2018 We place model-independent constraints on theories of massive spin-2 particles by considering the positivity of the phase shift in eikonal scattering. The phase shift is an asymptotic S-matrix observable, related to the time delay/advance experienced by ...
Kurt Hinterbichler +2 more
doaj +1 more source
Late time acceleration in Palatini gravity
Journal of High Energy Physics, 2022 We investigate the effect of the quadratic correction αR 2 and non-minimal coupling ξϕ 2 R on a quintessence model with an exponential potential V(ϕ) = M 4exp(−λϕ) in the Palatini formulation of gravity.
Ignatios Antoniadis +2 more
doaj +1 more source
Mimetic massive gravity: beyond linear approximation
Journal of High Energy Physics, 2018 We present a theory of ghost-free massive gravity where the mass of the graviton is generated through the Brout-Englert-Higgs (BEH) mechanism and one of the four scalar fields used is that of mimetic gravity.
Ali H. Chamseddine, Viatcheslav Mukhanov
doaj +1 more source
Recursion in the classical limit and the neutron-star Compton amplitude
Journal of High Energy Physics, 2023 We study the compatibility of recursive techniques with the classical limit of scattering amplitudes through the construction of the classical Compton amplitude for general spinning compact objects.
Kays Haddad
doaj +1 more source