[Binghamton Geometry/Topology Seminar] 3 talks this week

[Marco Varisco]

Binghamton Geometry/Topology Seminar
http://www.math.binghamton.edu/dept/topsem/

Three talks are scheduled for this week: one at the usual time on
Thursday, and two Friday afternoon.


-- First talk --

Date: Thursday, November 12, 2009

Time: 2:50-3:50 pm

Place: Library North 2205
(followed by coffee/tea in the Anderson Reading Room)

Speaker: Matt Rathbun (University of California, Davis)

Title: High distance knots in any 3-manifold

Abstract: Let M be a closed 3-manifold with a given Heegaard
splitting. We show that after a single stabilization, some core of the
stabilized splitting has arbitrarily high distance with respect to the
splitting surface. This generalizes a result of Minsky, Moriah, and
Schleimer for knots in S3. We also show that in the complex of curves,
handlebody sets are either coarsely distinct or identical. We define
the coarse mapping class group of a Heegaard splitting, and show that
if (S,V,W) is a Heegaard splitting of genus at least 4, then
CMCG(S,V,W)=MCG(S,V,W). This is joint work with Marion Moore.


-- Second talk --

Date: Friday, November 13, 2009

Time: 3:00-4:00 pm
(followed by coffee/tea in the Anderson Reading Room)

Place: Library North 2205

Speaker: Ian Hambleton (McMaster University)

Title: Conjugation spaces and 4-manifolds

Abstract: A conjugation space is a space X with involution, where the
cohomology mod 2 of the fixed set is the same as the cohomology of the
space after doubling dimensions. The first example is X = complex
projective space, with the involution given by complex conjugation. In
the talk I will describe the relation between smooth conjugation
4-manifolds and knotted surfaces in mod 2 homology 4-spheres. This is
joint work with Jean-Claude Hausmann.


-- Third talk --

Date: Friday, November 13, 2009

Time: 4:30-5:30 pm
(preceded by coffee/tea in the Anderson Reading Room)

Place: Library North 2205

Speaker: Kim Ruane (Tufts University)

Title: Automorphism groups of graph products

Abstract: In recent joint work with R. Charney, N. Stambaugh and A.
Vijayan we prove that a finite index subgroup of the automorphism
group of a certain type of graph product of finitely generated abelian
groups is again a graph product of finitely generated abelian groups.
The necessary condition is the "no SILS" condition discovered in
previous joint work of mine with A. Piggott and M. Gutierrez. If the
original graph product has all finite vertex groups, then this
condition implies that the outer automorphism group is finite. One
consequence of the new result is that these automorphism groups are
virtually CAT(0).