Current Seminars
updated 12/11/ 2001

 

As of December 11-14

 

Coverings of 3-Manifolds Seminar  *** Please note the change in time

Topic:         Universal covering spaces of closed 3-manifolds  Part III

Presenter:   Valentin Poenaru, Université de Paris-Sud (Orsay)

Date:          Tuesday, December 11, 2001, Time: 3:45 p.m., Location: Fine Hall 1201

 

Algebraic Geometry Seminar  *** Please note the change in location and time

Topic:        Gerbes of Higgs bundles and of bundles on genus-one fibrations 

Presenter:  Ron Donagi, University of Pennsylvania

Date:         Tuesday, December 11, 2001, Time: 3:30 p.m., Location: IAS SH-101

 

Department Colloquium

Topic:        Universal covering spaces of closed 3 manifolds are simply connected at infinity

Presenter:   Valentin Poenaru, Université de Paris-Sud (Orsay)

Date:         Wednesday,  December 12, 2001, Time: 4:30 p.m., Location: Fine Hall 314

 

Coverings of 3-Manifolds Seminar 

Topic:         Universal covering spaces of closed 3-manifolds  Part IV

Presenter:   Valentin Poenaru, Université de Paris-Sud (Orsay)

Date:          Thursday, December 13, 2001, Time: 3:00 p.m., Location: Fine Hall 1201

 

Discrete Mathematics Seminar

Topic:       The Perfect Graph Conjecture – Recent Work

Presenter:  Paul Seymour, Princeton University

Date:         Thursday, December 13, 2001, Time: 4:00 p.m., Location: Fine Hall 224

Abstract:     A graph is Berge if no induced subgraph is an odd cycle of length > 3 or its complement.  One of the most famous open conjectures in graph theory (due to Claude Berge in 1961) states that for any Berge graph, the number of colours need to colour it equals the size of the largest complete subgraph.  Recentely there has been some real progress on this problem, and it appears likely now that the problem will be solved soon.  The most obvious examples of Berge graphs are bipartite graphs, and their complements.  (Call these four types basic.)  There are lots of other examples, but ignore them: we think that in fact every Berge graph is either basic or can be built by piecing basic graphs together in an appropriate way.  If true , this immediately implies the perfect graph conjecture; and I am convinced it’s true, and think we are close to a proof.  The talk is a survey of recent work joint with Maria Chudnovsky, Neil Robertson, Chunwei Song and Robin Thomas.

 

Topolgy Seminar

Topic:       An integer valued SU(3) Casson invariant for homology 3-spheres 

Presenter:  Hans Boden, McMaster University

Date:         Thursday, December 13, 2001, Time: 4:00 p.m., Location: Fine Hall 314

 

Princeton/IAS Number Theory  Seminar

Topic:        Congruences between modular forms.

Presenter:   James Parson, Princeton University

Date:         Thursday, December 13, 2001, Time: 4:30 p.m., Location: Fine Hall 322

Abstract:    Since the 70s, the old subject of congruences between elliptic modular forms has been relevant to contemporary arithmetic issues. Some of the fundamental results on such congruences will be discussed and a new perspective based on the modular representation theory of reductive groups over local fields will be introduced.

 

Geometric Analysis Seminar

Topic:        Harmonic map between spheres

Presenter:   Tang Zizhou, Princeton University and Tsing Hua University

Date:          Friday, December 14, 2001, Time: 3:00 p.m., Location: Fine Hall 314

 

Topic:        On finiteness of Kleinian groups with small limit sets

Presenter:   Qing Jie, University of California at Santa Cruz

Date:          Friday, December 14, 2001, Time: 3:00 p.m., Location: Fine Hall 314