Geometric rigidity on Sobolev spaces with variable exponent and applications

We present extensions of rigidity estimates and of Korn’s inequality to the setting of (mixed) variable exponents growth. The proof techniques, based on a classical covering argument, rely on the log-Hölder continuity of the exponent to get uniform regularity estimates on each cell of the cover, and on an extension result à la Nitsche in Sobolev spaces with variable exponents. As an application, by means of Gamma-convergence we perform a passage from nonlinear to linearized elasticity under variable subquadratic energy growth far from the energy well.