%0 Journal Article
%T Conformal metric-affine gravities
%A Olmo, G. J.
%A Orazi, E.
%A Pradisi, G.
%J Journal of Cosmology and Astroparticle Physics
%D 2022
%V 10
%N 10
%I IOP Publishing Ltd
%@ 1475-7516
%G English
%F Olmo_etal2022
%O WOS:000878259300018
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5405), last updated on Sun, 20 Nov 2022 18:00:53 +0000
%X We revisit the gauge symmetry related to integrable projective transformations in metric-affine formalism, identifying the gauge field of the Weyl (conformal) symmetry as a dynamical component of the affine connection. In particular, we show how to include the local scaling symmetry as a gauge symmetry of a large class of geometric gravity theories, introducing a compensator dilaton field that naturally gives rise to a Stuckelberg sector where a spontaneous breaking mechanism of the conformal symmetry is at work to generate a mass scale for the gauge field. For Ricci-based gravities that include, among others, General Relativity, f(R) and f(R, R μnu R μnu) theories and the EiBI model, we prove that the on-shell gauge vector associated to the scaling symmetry can be identified with the torsion vector, thus recovering and generalizing conformal invariant theories in the Riemann-Cartan formalism, already present in the literature.
%K Gauss-Bonnet-Lovelock-Horndeski-Palatini etc gravity theories
%K modified gravity
%R 10.1088/1475-7516/2022/10/057
%U https://arxiv.org/abs/2207.12597
%U https://doi.org/10.1088/1475-7516/2022/10/057
%P 057-21pp