Columbia

Mon 30 Nov 2015, 3:00pm
Algebraic Geometry Seminar
MATH 126

Relative orbifold DonaldsonThomas theory and local gerby curves

MATH 126
Mon 30 Nov 2015, 3:00pm4:00pm
Abstract
In this talk I will introduce the generalization of relative DonaldsonThomas theory to 3dimensional smooth DeligneMumford stacks. We adopt Jun Li’s construction of expanded pairs and degenerations and prove an orbifold DT degeneration formula. I’ll also talk about the application in the case of local gerby curves, and its relationship to the work of OkounkovPandharipande and MaulikOblomkov.
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Mathematics, UBC

Mon 30 Nov 2015, 3:00pm
Harmonic Analysis Seminar
MATX 1102

Diophantine equations and discrete restriction theory

MATX 1102
Mon 30 Nov 2015, 3:00pm4:30pm
Abstract
In this twopart talk, we discuss a Fourieranalytic approach to solve translationinvariant systems of polynomial equations, when the variables lie in a dense subset of the integers. In the first part, we explain how discrete estimates in restriction theory come into play in this problem. In the second part, we show how to obtain weak restriction estimates by Bourgain's discrete version of the TomasStein argument.
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University of Connecticut/University of TexasSan Antonio

Tue 1 Dec 2015, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
ESB2012

Saddle Solutions of AllenCahn Equation on the Plane.

ESB2012
Tue 1 Dec 2015, 3:30pm4:30pm
Abstract
AllenCahn equation arises in the mathematical study of phase transition. Despite it's seemingly simple appearance, It has displayed very rich structure of solutions and involved with deep mathematics. In this talk, I will discuss the existence, symmetry and classification of saddle solutions of AllenCahn equation on the plane. In particular, I will describe the variational characterization of these solutions as a mountain pass solutions.
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UBC Math and PIMS

Wed 2 Dec 2015, 3:00pm
Probability Seminar
ESB 2012

A characterization of Liouville property

ESB 2012
Wed 2 Dec 2015, 3:00pm4:00pm
Abstract
Poisson boundary provides an integral representation of all bounded harmonic functions. We say that a Markov chain satisfies the Liouville property if all bounded harmonic functions are constant, that is the Poisson boundary is trivial.
The first part of the talk is a gentle introduction to Poisson boundary. Then I will state a new condition that is equivalent to the Liouville property and provide a proof of this equivalence. This talk is based on an ongoing work and will be selfcontained.
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Mainz

Fri 4 Dec 2015, 3:00pm
Department Colloquium
MATX 1100

Counting curves  complex and tropical

MATX 1100
Fri 4 Dec 2015, 3:00pm4:00pm
Abstract
A curve is called rational if it can be parametrized by rational functions. Counting the number of rational curves in the plane that contain a given number of points has been an old and interesting problem. The degree of a curve is the degree of a polynomial equation defining it. We all know that there is only one curve of degree one through any given pair of points in the plane because this is just a straight line. The answer to similar questions for higher degrees quickly becomes more difficult and interesting. To simplify the problem, one may map a curve in the complex twospace to the real twospace by applying a componentwise absolute value and logarithm. The resulting object is for good reasons called an amoeba  I will show some pictures. The amoeba retracts to its spine which is a much simpler convexgeometric object that is also called a tropical curve. Such can be counted essentially by hand. A proof that the resulting counts coincide with the original problem goes via a recent theory of logarithmic GromovWitten invariants.
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University of Toronto

Tue 5 Jan 2016, 3:30pm
Diff. Geom, Math. Phys., PDE Seminar
ESB2012

Vortex filaments in the Euler equation

ESB2012
Tue 5 Jan 2016, 3:30pm4:30pm
Abstract
Abstract: Classical fluid dynamics arguments suggest that in certain
limits, the evolution of thin vortex filaments in an ideal incompressible
fluid should roughly be governed by an equation called the binormal
curvature flow. However, these classical arguments rely on assumptions
that are so unrealistic that it would be hard even to extract from them a
precise conjecture that admits any realistic possibility of a proof. We
present a different approach to this question that yields a reasonable
formulation of a conjecture and strong supporting evidence, and that
clarifies the very substantial obstacles to a full proof. Parts of the
talk are based on joint work with Didier Smets and with Christian Seis
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Sat 9 Jan 2016, 9:00am
SPECIAL
MATX 1102

Qualifying Exams  Analysis

MATX 1102
Sat 9 Jan 2016, 9:00am12:00pm
Details
For more information on Qualifying Exams, please visit http://www.math.ubc.ca/Grad/QualifyingExams/index.shtml
Lunch will be provided in Math 125 for students writing the Analysis exam.
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Sat 9 Jan 2016, 1:00pm
SPECIAL
MATX 1102

Qualifying Exams  Algebra

MATX 1102
Sat 9 Jan 2016, 1:00pm4:00pm
Details
For more info, please visit http://www.math.ubc.ca/Grad/QualifyingExams/index.shtml
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Sat 9 Jan 2016, 1:00pm
SPECIAL
MATX 1102

Qualifying Exams  Differential Equations

MATX 1102
Sat 9 Jan 2016, 1:00pm4:00pm
Details
For more info, please visit http://www.math.ubc.ca/Grad/QualifyingExams/index.shtml
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UBC

Thu 14 Jan 2016, 3:30pm
Number Theory Seminar
room MATH 126

TBA

room MATH 126
Thu 14 Jan 2016, 3:30pm4:30pm
Abstract
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University of Iowa

Fri 15 Jan 2016, 3:00pm
Department Colloquium
MATH 1100

TBA

MATH 1100
Fri 15 Jan 2016, 3:00pm4:00pm
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Thu 21 Jan 2016, 3:30pm
Number Theory Seminar
room MATH 126


room MATH 126
Thu 21 Jan 2016, 3:30pm4:30pm
Abstract
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University of Ottawa

Thu 28 Jan 2016, 3:30pm
Number Theory Seminar
room MATH 126

Howe's notion of rank for Adele groups

room MATH 126
Thu 28 Jan 2016, 3:30pm4:30pm
Abstract
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Princeton University

Fri 26 Feb 2016, 3:00pm
SPECIAL
Department Colloquium / PIMS Seminars and PDF Colloquiums
ESB 2012

TBAPIMS/UBC Distinguished Colloquium

ESB 2012
Fri 26 Feb 2016, 3:00pm4:00pm
Abstract
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UC Berkeley

Fri 4 Mar 2016, 3:00pm
SPECIAL
Department Colloquium
ESB 2012

PIMS Hugh Morris Lecture

ESB 2012
Fri 4 Mar 2016, 3:00pm4:00pm
Abstract
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Harvard University

Fri 18 Mar 2016, 3:00pm
SPECIAL
Department Colloquium / PIMS Seminars and PDF Colloquiums
ESB2012

PIMSUBC Distinguished ColloquiumTBA

ESB2012
Fri 18 Mar 2016, 3:00pm4:00pm
Abstract
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Courant Institute, NYU

Fri 1 Apr 2016, 3:00pm
SPECIAL
Department Colloquium
ESB2012

PIMSUBC Distinguished ColloquiumTBA

ESB2012
Fri 1 Apr 2016, 3:00pm4:00pm
Abstract
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Fri 9 Sep 2016, 3:00pm
SPECIAL
ESB 2012

PIMSUBC Distinguished ColloquiumTBA

ESB 2012
Fri 9 Sep 2016, 3:00pm4:00pm
Details
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Note for Attendees
Refreshments will be served at 2:45pm in the Math Lounge area, MATH 125 before the colloquium.