Mark Kac Seminar
Location:
11:1513:00 
speaker: Silke Rolles (München) 
title: Bayesian analysis for reversible Markov chains 
We introduce
a natural conjugate prior for the transition matrix of a reversible
Markov chain. The prior arises from random walk with reinforcement in
the same way the Dirichlet prior arises from Polya's urn. 

4:1516:00 
speaker: Franz Merkl (München) 
title: What
are crystals? (3) 
abstract (for the
series): As is
wellknown from everyday knowledge, interacting molecules at thermal
equilibrium at low temperature form cristals. At higher temperature,
they undergo a melting transition to a liquid phase. From the viewpoint
of statistical mechanics, these wellknown facts are by far not
understood. The talks
are concerned with the notion of spontaneous symmetry breaking in
interacting particle systems. On the one hand, I will present a
(over)simplified model for a twodimensional continuum particle system
that spontaneously breaks rotational symmetry. On the other hand, by
the famous MerminWagner phenomenon, twodimensional particle systems
frequently show preservation of continuous symmetry. For example,
Richthammer has recently shown that translational symmetry is preserved
in twodimensional hardcore particle systems. The
MerminWagner phenomenon plays also a role in the recent understanding
of linearly edgereinforced random walks. There, absence of spontaneous
breaking of a certain scaling symmetry plays an essential role. 
Mark Kac Seminar 20082009 

last updated: 18 dec 2008by Markus 