The role of translational invariance in non linear gauge theories of gravity

The internal structure of the tetrads in a Poincar\'e non linear gauge theory of gravity is considered. Minkowskian coordinates becomes dynamical degrees of freedom playing the role of Goldstone bosons of the translations. A critical length allowing a covariant expansion similar to the weak field approach is deduced, the zeroth order metric being maximally symmetric (Minkowskian in some cases).Comment: 17 pages, LaTe

Dynamical variables in Gauge-Translational Gravity

Assuming that the natural gauge group of gravity is given by the group of isometries of a given space, for a maximally symmetric space we derive a model in which gravity is essentially a gauge theory of translations. Starting from first principles we verify that a nonlinear realization of the symmetry provides the general structure of this gauge theory, leading to a simple choice of dynamical variables of the gravity field corresponding, at first order, to a diagonal matrix, whereas the non-diagonal elements contribute only to higher orders.Comment: 15 page