HOROWITZ SEMINAR
PROBABILITY, ERGODIC THEORY and DYNAMICAL SYSTEMS
Monday, 19/1/2009, at 14:30 in: room 210, Schreiber Bldg.
Boris Begun (Hebrew U)
will speak on
Partitions with independent iterates.
Abstract:
(Joint work with A. del Junco)
Consider a measure-preserving transformation of a probability space.
A finite partition of the space is called weakly independent if there
are infinitely many images of this partition under powers of the
transformation that are jointly independent.
Krengel proved that a transformation is weakly mixing if and only if weakly independent
partitions of the underlying space are dense among all finite partitions.
This result has been generalized to actions of discrete amenable groups.
Now consider a random dynamical system (skew product) that is weakly
mixing relative to the base.
The independence of partitions can be defined in relation to the base.
Also in this relative setting there exists a counterpart of Krengel's result.
The principal ingredient of the proofs is a result on extension of stationary measures, in other words,
building stationary stochastic processes (with discrete time) from its marginals.
This result is probably interesting in its own right.
To suggest a talk (yours, or someone elses), contact
Jon. Aaronson:
aaro at post dot tau dot ac dot il
Last update on 12/10/08.