MG12 - Talk detail |
Participant |
LOPEZ-VILLAREJO, JUAN JOSE | |
Institution |
UNIVERSIDAD AUTONOMA MADRID - DPTO. FISICA TEORICA. FACULTAD DE CIENCIAS, CAMPUS DE CANTOBLANCO. - MADRID - MADRID - Spain | |
Session |
Talk |
Abstract |
MGAT3 |
Observational Constraints on Transverse Gravity: a generalization of Unimodular Gravity. |
We explore the hypothesis that the set of symmetries enjoyed by the theory that describes gravity is not the full group of Diffeomorphisms (Diff(M)), as in General Relativity, but a maximal subgroup of it (TransverseDiff(M)), with its elements having a Jacobian equal to unity; at the infinitesimal level, the parameter describing the coordinate change $xi^{\mu}(x)$ is transverse, i.e., $\partial_{\mu}\xi^{\mu}=0$. Incidentally, this is the smaller symmetry one needs to propagate consistently a graviton, which is a great theoretical motivation for considering these theories. Also, the determinant of the metric, g, behaves as a transverse scalar, so that these theories can be seen as a generalization of the better-known Unimodular Gravity. We present our results on the observational constraints on Transverse Gravity, in close relation with the claim of equivalence with general Scalar-Tensor Theory. We also comment on the structure of the divergences of the quantum theory to the one-loop order. |