In Fall 2010, we will meet on Tuesdays at 3:00pm in Room
3207, unless otherwise noted. The organizers of this seminar are Dan Lee and Marcello Lucia. Please
email Dan at Dan.Lee2(NoSpamPlease)qc.cuny.edu to schedule a guest
speaker.
The CUNY Graduate Center is located at 365 Fifth Avenue at 34th Street, diagonally across the street
from the Empire State Building, just two blocks from Penn Station (NYC).
Past Seminar Schedules and Abstracts:
Spring
2010,
Fall
2009,
SpringSummer
2009,
Fall 2008,
Spring 2008,
Fall 2007,
SpringSummer 2007,
Fall 2006,
SpringSummer 2006,
Fall 2005,
Spring 2005,
Fall
2004, Spring
2004, Fall
2003, Spring
2003, Fall
2002, Spring
2002, Fall
2001,
Spring
2001.
Fall 2010:

Tuesday, 8/31: We will play a video of a lecture by Gerhard Huisken
(Max Planck Institute)
An Isoperimetric Concept for the Mass in General Relativity
This is sort of an experiment. If it is successful, we may try it again.

Tuesday, 9/7: no seminar
9/6 is Labor Day
 Tuesday, 9/14 at 1:00pm in Math Thesis Room (note special time
and room): Tom Koornwinder
(University of Amsterdam)
The Askey scheme as a fourmanifold with corners
Abstract: Racah and Wilson polynomials with dilated and translated
argument are
reparametrized such that the polynomials are continuous in the parameters
as long as these are nonnegative, and such that restriction of one or more
of the new parameters to zero yields orthogonal polynomials lower in the
Askey scheme. Geometrically this will be described as a manifold with
corners.
Reference: Ramanujan J. 20 (2009), 409439; arXiv:0909.2822

Tuesday, 9/21: Victor Alvarez (CUNY Graduate Center)
The BrendleMarquesNeves counterexample to the MinOo Conjecture

Tuesday, 9/28: no seminar

Tuesday, 10/5: Chenxu He (Lehigh University)
Nonnegatively curved cohomogeneity one manifolds
Abstract: Manifolds with positive or nonnegative sectional curvature have
been of interest from the beginning of the global Riemannian geometry. It
is always a difficult problem to construct such examples. K. Grove and W.
Ziller discovered many new examples with nonnegatively curved metrics in
cohomogeneity one manifolds, i.e., they support an isometric action with
one dimensional orbit.
However not every cohomogeneity one manifold admits an invariant metric
with nonnegative curvature. The first examples of obstructions were
founded by K. Grove, B. Wilking, L. Verdiani and W. Ziller and then they
were generalized to a large family. In this talk I will also present
recent progress of finding new examples of cohomogeneity one manifolds
under various geometric and topological restrictions.

Tuesday, 10/12: no seminar
10/11 is Columbus Day

Tuesday, 10/19: Gabor Szekelyhidi (Columbia University)
On blowing up extremal Kahler manifolds
Abstract: I will talk about recent progress on constructing extremal
metrics on blowups building on the work of ArezzoPacardSinger.

Tuesday, 10/26: Lu Wang (MIT)
Bernstein type theorem for selfsimilar shrinkers
Abstract: I will talk about the Bernstein type theorem for
selfshrinkers of mean curvature flow. Namely, the only smooth
selfshrinkers, that are entire graphs, are
hyperplanes in Euclidean space. Reference: http://arxiv.org/abs/0912.1809

Tuesday, 11/2: no seminar

Tuesday, 11/9: Longzhi Lin (Johns Hopkins University)
Modified Mean Curvature Flow of Starshaped Hypersurfaces in Hyperbolic
Space
Abstract: Abstract: I will talk about my recent joint work with Ling
Xiao on the modified mean curvature flow (MMCF) of starshaped
hypersurfaces in hyperbolic space with fixed prescribed asymptotic
boundary at infinity. As an application, this recovers the existence and
uniqueness of smooth complete hypersurfaces of constant mean curvature in
hyperbolic space with prescribed asymptotic boundary at infinity, which
was first shown by Guan and Spruck.
Reference: http://arxiv.org/abs/1010.2091

Tuesday, 11/16: William Wylie (University of Pennsylvania)
On warped product Einstein metrics
Abstract: We discuss questions about when a Riemannian manifold is the
base of a warped product Einstein metric. There is a complete
classification in dimensions one and two, but there are interesting
examples in higher dimensions. A special (and exceptional) case are
static metrics, which arise in considerations regarding general relativity
and the positive mass theorem. Recently these spaces have also been of
new interest because of their similarity to the Ricci soliton equation and
because of their connection to optimal transport theory on Riemannian
manifolds. In this talk I'll discuss these motivations and describe some
new results and examples which arise from this viewpoint. This is joint
work with Chenxu He of Lehigh and Peter Petersen of UCLA.