University of Britich Columbia

Abstract:

In generic far-away-from-equilibrium many-body quantum dynamics, Gibbs entropy production is nonzero leading to the irreversibility of many-body unitary dynamics. Unless a quantum system is fully integrable (i.e. with an infinite number of conserved parameters) or infinitely constrained, the irreversibility in non-equilibrium dynamics is usually very robust. In this talk, I will discuss a class of fully reversible quantum dynamics that emerge in our recent studies of high dimensional scale invariant interacting quantum gases. I am going to illustrate how the scale-conformal invariance can result in perfectly oscillatory dynamic states of strongly interacting fermions or bosons, similar to perpetual time crystals. In some cases, such dynamics can also occur as emergent infrared phenomena even when strong interactions break scale symmetry explicitly. Towards the end, I will briefly comment on the imaginary time evolution of primary conformal operators and their connection to the physical dynamics states of many fermions and bosons.

Place:N301, Teaching Bldg, UCAS Zhong-Guan-Cun Campus