Abstract:
Gauge symmetries lead to first-class constraints. This assertion is, of course, true only for non-trivial gauge symmetries, i.e., gauge symmetries that act non-trivially on-shell on the dynamical variables. We illustrate this well-appreciated fact for time reparametrization invariance in the context of modifications of gravity – suggested in a recent proposal by Hořava – in which the Hamiltonian constraint is deformed by arbitrary spatial diffeomorphism invariant terms, where some subtleties are found to arise.
Citation:
Marc Henneaux, Axel Kleinschmidt, Gustavo Lucena Gómez, “Remarks on gauge invariance and first-class constraints”, Problems of modern theoretical and mathematical physics: Gauge theories and superstrings, Collected papers. Dedicated to Academician Andrei Alekseevich Slavnov on the occasion of his 70th birthday, Trudy Mat. Inst. Steklova, 272, MAIK Nauka/Interperiodica, Moscow, 2011, 152–161; Proc. Steklov Inst. Math., 272 (2011), 141–150