Irreversibility and the Arrow of Time

by Jürg Fröhlich (ETH-Zürich)

Monday 8 Jun 2026, 14:30 → 16:30 Europe/Rome

1/2-2 - Aula C (Dipartimento di Fisica e Astronomia - Edificio Marzolo)

A mathematical analysis of irreversible behavior and its origins in
various physical systems is presented.

The lecture will begin with a brief review of relative entropy and with
a survey of sources of irreversible behavior.

Subsequently, the Second Law of thermodynamics, in the forms given to
it by Clausius and Carnot, is derived from quantum statistical mechanics.

In a third part, a derivation of Brownian motion of a quantum particle
interacting with a quantum-mechanical heat bath is sketched. This is
followed by an outline of a theory of Hamiltonian Friction.

In what may be the most important part of the lecture, the fundamental
arrow of time inherent in Quantum Mechanics is discussed.