Lorentz invariance violations in the interplay of quantum gravity with matter

Abstract

We explore the interplay of matter with quantum gravity with a preferred frame to highlight that the matter sector cannot be protected from the symmetry-breaking effects in the gravitational sector. Focusing on Abelian gauge fields, we show that quantum gravitational radiative corrections induce Lorentzinvariance-violating couplings for the Abelian gauge field. In particular, we discuss how such a mechanism could result in the possibility to translate observational constraints on Lorentz violation in the matter sector into strong constraints on the Lorentz-violating gravitational couplings.

Cosmology and the massive photon frequency shift in the Standard-Model Extension

“…This is the viewpoint we adopt here. It is, however, a relevant matter, for future work to consider the presence of LSV in the gravitational sector [60][61][62][63][64][65] of SME and thereby reassess its effect on the red shift.…”

Extended Hořava Gravity with Physical Ground-State Wavefunction

“…In addition, full RG flow analysis of the model along [76] is needed to show whether GR is really a fixed point of the model. In the case that it fails to flow to GR (i.e., if λ does not flow to 1 in the IR), the model reduces to a LIV gravitational theory, and thus it could be incompatible with experiments on LIV in the matter sector at low energies [67]. As a last point, it is also valuable to investigate the possible relation at the quantum level of our model with models such as the Gravity's Rainbow [77].…”

“…The IR behavior of the BPS model is compatible with many current observations, such as binary pulsar [11], gravitational waves [2,13], and binary black hole [15] . However, if λ does not flow to 1 in the IR, General Relativity is not recovered at low energies, and the theory reduces to a LIV gravitational theory, which could be incompatible with current experiments [67]. We leave the full investigation for future work.…”

Critical Reflections on Asymptotically Safe Gravity

“…In this case, spacetime has a built-in foliation structure which defines a natural time direction. A first investigation of Asymptotic Safety in this framework has been performed in [441] and further developed in a series of works [226,[442][443][444][445][446][447][448]. This provided firsthand indications that the asymptotic-safety mechanism remains operative for Lorentzian signature metrics as well, at least within very small truncations.…”