Operator Growth in Disordered Spin Chains: Indications for the Absence of Many-Body Localization

A. Weisse, R. Gerstner, J. Sirker

We consider the spreading of a local operator $A$ in one-dimensional systems with Hamiltonian $H$ by calculating the $k$-fold commutator $[H,[H,[...,[H,A]]]]$. We derive bounds for…