Arrow of time (1983 --->)

Why does a cup of tea get cold? Why can’t things come out of black holes the way the enter? Why does the Universe keep expanding? Why does life evolve into more and more complex life forms?

Do these questions have anything to do with each other, except to say that they are all examples of arrows of time?

In this talk I will focus on the first two arrows, and mention some related aspects of my arrow of research, starting from 1983 onwards. I will also try to convince you that these two arrows are rather closely related.

The technical part of my talk will describe a  number of ways in which systems out of equilibrium thermalize, with examples ranging from black hole evaporation to post-quench thermalization in conformal field theories and in one dimensional Fermi gas. The last example shows a new mechanism of thermalization of Fermi fluids through filamentation of phase space droplets.