On a lack of stability of parametrized BV solutions to rate‐independent systems with nonconvex energies and discontinuous loads

Abstract

We consider a rate-independent system with nonconvex energy under discontinuous external loading. The underlying space is finite-dimensional and the loads are functions in 𝐵⁢𝑉⁡([0,𝑇];ℝ𝑑). We investigate the stability of various solution concepts w.r.t. a sequence of loads converging weakly* in 𝐵⁢𝑉⁡([0,𝑇];ℝ𝑑) with a particular emphasis on the so-called normalized, 𝔭-parametrized balanced viscosity solutions. By means of three counterexamples, it is shown that common solution concepts are not stable w.r.t. weak* and even intermediate (or strict) convergence of loads in the sense that a limit of a sequence of solutions associated with these loads need not be a solution corresponding to the load in the limit. We moreover introduce a new solution concept, which is stable in this sense, but our examples show that this concept necessarily allows “solutions” that are physically meaningless.