UBC

Tue 15 Oct 2019, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
Buchanan D307

Harmonic maps on simplicial complexes

Buchanan D307
Tue 15 Oct 2019, 3:30pm4:30pm
Abstract
Harmonic maps have found various applications in Teichmuller theory. While Teichmuller space describes conformal (or hyperbolic) structures on a surface, harmonic maps provide a parametrization on Teichmuller space (via their Hopf differentials) as well as a distance function (the Teichmuller metric). Beginning with a 2dimensional simplicial complex, we first describe several spaces of metrics. We then show the existence of harmonic maps between such spaces, in the hopes of adding the analytic tools of harmonic maps to the Teichmuller spaces of simplicial complexes. This is joint work with Victoria Gras Andreu.
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SFU

Tue 15 Oct 2019, 4:00pm
Discrete Math Seminar
ESB 4127

Graphs with high cop number

ESB 4127
Tue 15 Oct 2019, 4:00pm5:00pm
Abstract
We explore classes of graphs on which a large number of pursuers are required to capture an evader. We give a lower bound for the cop number of graphs of high girth that improves a result of P. Frankl. We also consider lower bounds for the cop number of various algebraically constructed graph classes. In particular, we present a class of directed graphs with cop number (1o(1)) \sqrt{n}, which is greater than any lower bound currently known for any directed graph class.
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UBC

Wed 16 Oct 2019, 2:45pm
Mathematical Biology Seminar
ESB 4133

Humanbased organ models as tools for (patho)physiological research in human epithelia

ESB 4133
Wed 16 Oct 2019, 2:45pm3:45pm
Abstract
The Hedtrich lab is developing humanbased organ models with a current focus on skin and lung. They are specifically interested in the modeling of inflammatory and genetic diseases in vitro and use the organ models to study (patho)physiological mechanism. In this talk, Dr. Hedtrich will give an overview of the different approaches in her lab has with emphasize on their work done in atopic diseases and the atopic march.
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UBC

Wed 16 Oct 2019, 2:45pm
Topology and related seminars
ESB 4127 (PIMS)

On symmetries of peculiar modules; or, \deltagraded link Floer homology is mutation invariant

ESB 4127 (PIMS)
Wed 16 Oct 2019, 2:45pm3:45pm
Abstract
Conway mutation is an operation on links that is notoriously
difficult to detect: it preserves many link invariants such as
the signature, the Alexander polynomial or, more generally, the
HOMFLY polynomial. Baldwin and Levine conjectured that δgraded
link Floer homology also belongs in this list—despite the fact
that *bigraded* link Floer homology can distinguish some mutant
knots such as the famous KinoshitaTerasaka and Conway knots.
In [arXiv:1909.04267], I proved Baldwin and Levine's conjecture
by studying symmetry properties of peculiar modules, an immersed
curve invariant of 4ended tangles. In this talk, I will sketch
this proof.
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Cornell University

Wed 16 Oct 2019, 3:00pm
Probability Seminar
ESB 1012

Multiple players ruin problems and the Dirichlet heat kernel in compact inneruniform domains

ESB 1012
Wed 16 Oct 2019, 3:00pm4:00pm
Abstract
We describe detailed twosided inequalities for the threeplayer ruin problem and related estimates for killed random walks in inneruniform finite subset of grids and other graphs. The key is the simultaneous use of the appropriate Doob transform, doubling and Poincaré inequalities. This talk is based on joint work with Persi Diaconis and Kelsey HoustonEdwards.
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Cornell University

Fri 18 Oct 2019, 3:00pm
Department Colloquium
ESB 1012 (PIMS/UBC Distinguished Colloquium)

Doubling geometries on compact Lie groups

ESB 1012 (PIMS/UBC Distinguished Colloquium)
Fri 18 Oct 2019, 3:00pm4:00pm
Abstract
The "doubling property" refers to the property (of a metric measure space) that max{Vol(B(x,2r))/Vol(B(x,r)): r>0} is bounded. We consider the following question: do we have good control of the doubling property for leftinvariant geometries on a given compact Lie group? For instance, on the group SU(2) (which, as a manifold, is the 3sphere) what can we say of the doubling constant of a leftinvariant geometry? We will discuss the conjecture that, for any compact Lie group G, there is a constant D(G) such that max{Vol_g(2r)/Vol_g(r): r>0} is bounded by D(G) uniformly over all leftinvariant metric g. This is true in the case of SU(2). This talk is based on joint work with Nate Eldredge and Maria Gordina.
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Note for Attendees
Refreshments will be served at 2:30 p.m. in ESB 4133 (Lounge).