Entanglement wedge cross section growth during thermalization

Abstract

Motivated by exploring the thermalization process in relativistic and nonrelativistic holographic field theories after a nonlocal quench, we investigate some features in the time evolution of the entanglement wedge cross section (EWCS). This quantity is a possible holographic dual to some nonlocal information measures such as entanglement of purification. In particular, we focus on the time dependence of the EWCS during black hole formation in ($D+2$)-dimensional anti--de Sitter spacetime as well as geometries with Lifshitz and hyperscaling-violating exponents. A combination of analytic and numerical results for large symmetric strip shaped boundary subregions shows that the scaling of the EWCS at early times only depends on the Lifshitz exponent. In addition, this early-growth regime is followed by a linear-growth regime whose velocity depends on the dimensions of spacetime, the Lifshitz exponent, and the hyperscaling parameter. This velocity is the same as the entanglement velocity and for nontrivial dynamical exponent depends on the temperature of the final equilibrium state.