Gravity as a deformed topological gauge theory

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Thibaut, J., Lazzarini, S.
Format: Preprint
Publié: 2024
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866908749925449728
author Thibaut, J.
Lazzarini, S.
author_facet Thibaut, J.
Lazzarini, S.
contents We describe gauge theories which allow to retrieve a large class of gravitational theories, including, MacDowell-Mansouri gravity and its topological extension to Loop Quantum Gravity via the Pontrjagin characteristic class involving the Nieh-Yan term. Considering symmetric spaces parametrized by mutations allows to naturally obtain a bare cosmological constant which in particular cases gives rise to a positive effective cosmological constant while having an AdS spacetime. Two examples are studied, Lorentzian geometry (including dS and AdS spacetimes) and Lorentz$\times$Weyl geometry. In the latter case we prove the equations of motion exhibit a secondary source for curvature in addition to the usual energy-momentum tensor. This additional source is expressed in terms of the spin density of matter, torsion and their variations. Finally, we show that the gauge + matter actions constructed from invariant polynomials are asymptotically topological if one assumes a vanishing bare cosmological constant together with gauge and matter fields having compact support.
format Preprint
id arxiv_https___arxiv_org_abs_2403_05284
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Gravity as a deformed topological gauge theory
Thibaut, J.
Lazzarini, S.
General Relativity and Quantum Cosmology
Mathematical Physics
83Cxx, 70S15
We describe gauge theories which allow to retrieve a large class of gravitational theories, including, MacDowell-Mansouri gravity and its topological extension to Loop Quantum Gravity via the Pontrjagin characteristic class involving the Nieh-Yan term. Considering symmetric spaces parametrized by mutations allows to naturally obtain a bare cosmological constant which in particular cases gives rise to a positive effective cosmological constant while having an AdS spacetime. Two examples are studied, Lorentzian geometry (including dS and AdS spacetimes) and Lorentz$\times$Weyl geometry. In the latter case we prove the equations of motion exhibit a secondary source for curvature in addition to the usual energy-momentum tensor. This additional source is expressed in terms of the spin density of matter, torsion and their variations. Finally, we show that the gauge + matter actions constructed from invariant polynomials are asymptotically topological if one assumes a vanishing bare cosmological constant together with gauge and matter fields having compact support.
title Gravity as a deformed topological gauge theory
topic General Relativity and Quantum Cosmology
Mathematical Physics
83Cxx, 70S15
url https://arxiv.org/abs/2403.05284