Perlen-Kolloquium - Jürg Fröhlich
Jürg Fröhlich (ETH Zürich): The Arrow of Time
This is a survey of effective dynamics in quantum theory and of sources of irreversible behavior. After a short
recap of properties of (relative) entropy, the following examples of irreversible behavior are discussed:
(1) The second law of thermodynamics is discussed within quantum statistical mechanics.
(2) It is indicated how Brownian motion of a quantum particle immersed in a heat bath can be derived from unitary quantum dynamics of the total system.
(3) Motion with friction is discussed in an example of Hamiltonian evolution equations for a particle moving through a dispersive wave medium.
(4) It is sketched that and why quantum dynamics is fundamentally irreversible.