The quasiconvex envelope of conformally invariant planar energy functions in isotropic hyperelasticity

Robert J. Martin, Jendrik Voss, Ionel-Dumitrel Ghiba +2

We consider conformally invariant energies $W$ on the group ${\mathrm{GL}}^{+}(2)$ of $2\times 2$-matrices with positive determinant, i.e. $W\colon\operatorname{GL}^+(2)\to\mathbb…