The GT seminar meets on Fridays
in Math. 520,
at 1:15PM.
Organizer:
Walter Neumann.
Other
area seminars. Our e-mail
list. Archive of previous semesters
FALL 2011
| Date | Speaker | Title |
|---|---|---|
| January 19, 3pm Room 528 |
Dani Wise | Quasiconvex Subgroups of Relatively Hyperbolic groups |
| January 20 | Everyone | Organizational meeting joint with SGGTC seminar |
| January 27 | Jose Luis Cisneros-Molina | Geometric elements in algebraic K-Theory |
| February 3 | Tudor Dimofte | Non-Abelian Torsion and the Neumann-Zagier Equations |
| February 10 | David Futer | The Jones polynomial and surfaces far from fibers |
| February 17 | Craig Hodgson | TBA |
| February 24 | TBA | TBA |
| March 2 | Elizabeth Denne | Transversality theorems for configuration spaces and applications to the "square peg" problem. |
| March 9 | TBA | TBA |
| March 16 | Spring Break | Spring Break |
| March 23 | Khalid Bou Rabee | TBA |
| March 30 | Harriet Moser | TBA |
| April 6 | Matthias Kreck | TBA |
| April 13 | TBA | TBA |
| April 20 | Yi Liu | TBA |
| April 25? | Howie Masur | Note changed date |
| April 27 | TBA | TBA |
| May 4 | TBA | TBA |
| May 11 | TBA | TBA |
Abstracts.
January 19. Note room change: Math 528
Dani Wise, “Quasiconvex Subgroups of Relatively Hyperbolic groups ”
Abstract: I will review Bowditch's treatment of a relatively hyperbolic group, and in that context, describe an elegant reformulation of the notion of "relatively quasiconvex subgroup" introduced with Eduardo Martinez-Pedroza. I will then describe work with Hadi Bigdely that applies this criterion to recognize the relative quasiconvexity of a subgroup H in a group G splitting as a graph of groups. The simplest applications revisit beautiful work of Dahmani and others.
January 27
Jose Luis Cisneros-Molina “Geometric elements in algebraic K-Theory”
Abstract: In this talk we show how to represent elements in $K_3(C)$ using homology 3-spheres and hyperbolic 3-manifolds endowed with a representation of their fundamental group. We review some results of Jones and Westbury and the relation of such elements with the Bloch invariant defined by Neumann and Yang.
February 3
Tudor Dimofte “Non-Abelian Torsion and the Neumann-Zagier Equations”
Abstract: I will present an extraordinarily simple formula for the torsion of a hyperbolic 3-manifold M in terms of shape parameters and gluing matrices involved in an ideal triangulation. The torsion appears (for example) as the first subleading correction to the large-N asymptotics of the Kashaev invariant of M. The formula immediately shows that the torsion belongs to the invariant trace field of M. (This is ongoing work with S. Garoufalidis.)
February 10
David Futer “The Jones polynomial and surfaces far from fibers”
Abstract: This talk explores relations between colored Jones polynomials and the topology of incompressible spanning surfaces in knot and link complements. Under mild diagrammatic hypotheses, we prove that the growth of the degree of the colored Jones polynomials is a boundary slope of an essential surface in the knot complement. We also show that certain coefficients of the Jones and colored Jones polynomials measure how far this surface is from being a fiber in the knot complement. This is joint work with Effie Kalfagianni and Jessica Purcell.
Mar 2
Elizabeth Denne “Transversality theorems for configuration spaces and applications to the "square peg" problem.”
Abstract: In joint work with Jason Cantarella and John McCleary, we prove a transversality "lifting property" for compactified configuration spaces. Namely, the submanifold of configurations of points on an arbitrary submanifold of Euclidean space may be made transverse to any submanifold of the configuration space of points in Euclidean space by an arbitrarily small variation of the initial submanifold, as long as the two submanifolds of configuration space are boundary-disjoint. We use this setup to provide proofs of a number of "special inscribed configurations" using differential topology. For instance, there are an odd number of inscribed squares in a generic plane curve, while there is a family of inscribed regular (n+1)-simplices in a generic (n-1)-sphere.
Other relevant information.
Previous semesters:
Fall 2011, 2010/11, Spring 2010, Fall 2009, Spring 2009, Fall 2008, Spring 2008, Fall 2007, Spring 2007, Fall 2006.Other area seminars.
- Columbia Symplectic Geometry/Gauge Theory Seminar
- All Columbia Math Dept Seminars
- CUNY Geometry and Topology Seminar
- CUNY Complex Analysis & Dynamics Seminar
- CUNY Magnus Seminar
- Princeton Topology Seminar.
Our e-mail list.
Announcements for this seminar, as well as for related seminars and events, are sent to the GT seminar mailing list. You can subscribe directly or by contacting Walter Neumann.