Alessio Lerose (University of Oxford)

Quasi-localized dynamics and metastable spatiotemporal order in synthetic matter

Even in generic quantum many-body systems without nontrivial conservation laws and without quenched disorder, the non-equilibrium evolution of certain initial states can exhibit an extraordinary resilience to dynamical relaxation to equilibrium. A celebrated phenomenon of this kind is the metastability of "false vacua” discussed long ago in the context of relativistic quantum field theory by S. Coleman and others. Recently, several instances of suppressed thermalization have been discovered in the context of synthetic quantum matter - highly coherent quantum many-particle systems governed by largely programmable Hamiltonian interactions. In this talk I will discuss versions of the former phenomenon in the latter context: What do the analog of familiar metastability phenomena from high-energy physics look like in low-energy synthetic matter setups? I will show that genuinely new and surprising behavior appears, including emergent quasi-localized dynamics of interfaces and metastable spatiotemporal long-range order.