Data inizio

22/09/2026 12:30

Data fine

22/09/2026 14:30

Luogo

Dipartimento di Fisica - A501

Relatori

Davide Rovere
Ecole Polytechnique

In this talk, based on 2505.21022, the relation between covariant fractons and Møller-Hayashi-Shirafuji extension of Einstein Gravity is discussed, providing a first insight in the non-linear extension of covariant fracton theories. The so-called "covariant fracton gauge theories" are a family of Lorentz-covariant extensions of the gauge theory of fractons, which are quasiparticles excitations with reduced mobility, due to the conservation of the dipole moment. In the usual formulation of Einstein Gravity, the dynamical variables are encoded in the (Riemann) curvature of the torsionless (Levi-Civita) connection. Equivalently one can choose a flat torsionful connection: in this formulation, first considered by Weitzenböck, the action of the theory is quadratic in the torsion. The most general quadratic action defines a family of extensions of Einstein Gravity, first studied by Møller and by Hayashi and Shirafuji. As a result, the space of classical solutions of covariant fracton theories can be identified with a subsector of the space of classical solutions of linearised Møller-Hayashi-Shirafuji theories.