BGU Set Theory and Topology Seminar Archive
Wednesday, April 24, 14:00,
room -101, the math building.
Speaker: Victoria Lubitch
Topic: Linearly Lindelof non Lindelof spaces II
Wednesday, April 10, 14:00,
room -101, the math building.
Speaker: Victoria Lubitch
Topic: Linearly Lindelof non Lindelof spaces
Abstract: Construction of sequentially linearly Lindelof
space from good scale of cardinality \aleph_{\omega +1} . Construction of
realcompact linearly lindelof space under assumption 2^{\omega} =
\aleph_{\omega + 1} and existing of good scale. (Partial solution of
Archangel'skii problem). Conditions when product of two sequentially linearly
Lindelof spaces is linearly Lindelof. Tatch Moore example LLnL space as product
regular lindelof space and separable metric space (assumption
2^{\aleph_{\omega}} > \aleph_{\omega+1}). Kunen example of locally compact
LLnL space.
Wednesday, March 20, 14:00,
room -101(?), the math building.
Speaker: Michael Levin
Topic: Free actions of compact 0-dimensional
groups
Abstract: We will discuss basic results, methods and
conjectures.
Wednesday, February 27,
12:00, room -101, the math building.
Speaker: Istvan Juhasz (Budapest)
Topic: of his choice
Friday, February 15, 10:00,
room -101, the math building.
Speaker: Istvan Juhasz (Budapest)
Topic: Calibers, free sequences and density
Abstract: Results from a joint work with Z.
Szentmiklossy. Below you can download the DVI, PS and PDF file.
NOTE: The last
seminar in this semester
Wednesday, January 9, 14:30,
room 201, the math building.
Speaker: Edmund Ben-Ami
Topic: Another proof of the Open Mapping
Principle (III)
Wednesday, January 2, 14:30,
room 201, the math building.
Speaker: Arkady Leiderman
Topic: On transitive actions and homogeneous
spaces
Wednesday, December 26,
14:00, room 201, the math building.
Speaker: Edmund Ben-Ami
Topic: Another proof of the Open Mapping
Principle (II)
Wednesday, December 19,
14:00, room 201, the math building.
Speaker: Edmund Ben-Ami
Topic: Another proof of the Open Mapping
Principle
Wednesday, December 12,
14:00, room 201, the math building.
Speaker: Wieslaw Kubis
Topic: Minimal discrete and continuous flows
Abstract: A flow is, by the definition, an
action of G on a topological space X, where G is either the group of integers
or the group of the real numbers; we add the adjective discrete or continuous
to specify the group. An interesting problem is which topological spaces admit
minimal flows (a flow is minimal if all its orbits are dense). I will
describe some examples and results. Finally, I will prove that if a Hausdorff
space X admits a flow whose all forward orbits are dense then X is either
compact or else X is nowhere locally compact.
Wednesday, December 5,
14:30, room 201, the math building.
Speaker: Dr. Michael Megrelishvili (Bar-Ilan
University)
Topic: Reflexive representations of topological
groups and G-spaces
Abstract: The talk will be devoted to the following
author's results:
Theorem 1 A topological group G embeds into the
isometry group of a reflexive Banach space if and only if weakly almost
periodic functions separate points and closed subsets in G.
Theorem 2 The group Homeo_{+} [0,1] of
orientation-preserving homeomorphisms of the usual segment [0,1] with the
compact-open topology admits no non-trivial strongly continuous representations
in reflexive Banach spaces.
Friday, November 30, 10:00,
room -101, the math building.
Speaker: Arkady Leiderman
Topic: Actions of general topological groups IV
(continuation)
Abstract: The last lecture on effective actions of
topological groups.
Wednesday, November 14,
14:00, room 201, the math building.
Speaker: Arkady Leiderman
Topic: Actions of General topological groups III
(continuation)
Abstract: Proofs of the two classical theorems due
to Teleman and Veech respectively: Every Hausdorff topological group acts
effectively on a compact space; every locally compact group acts freely on a
compact space.
Wednesday, November 7,
14:00, room 201, the math building.
Speaker: Arkady Leiderman
Topic: Actions of General topological groups II
(the continuation)
Abstract: I 'm going to present proofs of the two
classical theorems:
Theorem 1 (Teleman) Every Hausdorff topological group
acts effectively on a compact space.
Theorem 2 (Veech) Every locally compact group acts
freely on a compact space.
Wednesday, October 31,
14:00, room 201, the math building.
Speaker: Arkady Leiderman
Topic: Actions of General topological groups
Abstract: I am planning to give 2 or 3 lectures. In
the first lecture I want to remind basic notions from the theory of topological
groups. Then, in the next lectures I'd like to present proofs of the two
classical theorems:
Theorem 1 (Teleman) Every Hausdorff topological group
acts effectively on a compact space.
Theorem 2 (Veech) Every locally compact group acts
freely on a compact space.
