Game theory of generalized selection hypotheses
- Speaker(s)
- Boaz Tsaban
- Affiliation
- Weizmann Institute of Science
- Date
- Nov. 15, 2004, 2:15 p.m.
- Information about the event
- 5081
- Seminar
- Topology and Set Theory Seminar
Abstract:
This talk is an opportunity to get acquainted with the
basic definitions and some elementary techniques
used in the new field often called "selection principles".
We will do that by introducing one aspect of the field
only: That of topological games.
Motivated by a question of Iliadis, Scheepers' prototypes
of topological diagonalizations are extended to the case
that the types of covers in the sequence to be diagonalized
can vary.
A known example of such a property which
cannot be expressed by Scheepers' prototypes is the
Galvin-Miller strong gamma-property.
Whereas this property is strictly stronger
than the Gerlits-Nagy gamma property,
the corresponding strong notions for the
Menger, Hurewicz, Rothberger, Gerlits-Nagy (*),
Arkhangel'skii and Sakai
properties are equivalent to the original ones.
(All these properties will be defined in the
talk.)
We give new game theoretic characterizations for
most of these properties, and pose several
interesting open problems.
No background is assumed and the talk will be
aimed at a general mathematical audience.
All needed definitions will be provided,
and most of the proofs will be given or at least
sketched. As much time as required will be
dedicated to answering questions of the audience.
The talk is an extended version of a planned talk
in the upcoming Bonn Conference on infinite games.