# Upcoming Seminars

Title: Wave decay for star-shaped waveguides
Seminar: Analysis and PDE
Speaker: Kiril Datchev of Purdue
Contact: Yiran Wang, yiran.wang@emory.edu
Date: 2020-02-20 at 2:30PM
Venue: MSC N306
Abstract:
Let $\Omega \subset \mathbb R^d$ be an unbounded open set. We wish to understand how decay of solutions to the wave equation on $\Omega$ is related to the geometry of $\Omega$.\\ \\ When $\mathbb R^d \setminus \Omega$ is bounded, this is the celebrated obstacle scattering problem. Then a particularly favorable geometric assumption, going back to the original work of Morawetz, is that the obstacle is star shaped. We adapt this assumption to the study of waveguides, which are domains bounded in some directions and unbounded in others, such as tubes or wires. We prove sharp wave decay rates for various waveguides, including the example of a disk removed from a straight planar waveguide, that is to say $\Omega = ((-1,1) \times \mathbb R) \setminus D$, where $D$ is a closed disk contained in $(-1,1) \times \mathbb R$. Our results are based on establishing estimates and pole-free regions for the resolvent of the Laplacian near the continuous spectrum.\\ \\ This talk is based on joint work with Tanya Christiansen.
Title: Linear and rational factorization of tropical polynomials
Seminar: Algebra
Speaker: Bo Lin of Georgia Tech
Contact: David Zureick-Brown, DAVID.M.BROWN.JR@GMAIL.COM
Date: 2020-02-25 at 4:00PM
Venue: MSC W303
Abstract:
Already for bivariate tropical polynomials, factorization is an NP-Complete problem. In this talk, we will introduce a rich class of tropical polynomials in n variables, which admit factorization and rational factorization into well-behaved factors. We present efficient algorithms of their factorizations with examples. Special families of these polynomials have appeared in economics, discrete convex analysis, and combinatorics. Our theorems rely on an intrinsic characterization of regular mixed subdivisions of integral polytopes, and lead to open problems of interest in discrete geometry.
Title: TBA
Defense: Number Theory
Speaker: Lea Beneish of Emory University
Contact: David Zureick-Brown, DAVID.M.BROWN.JR@GMAIL.COM
Date: 2020-03-03 at 3:00PM
Venue: MSC W303
Abstract:
Title: TBA
Defense: Algebra
Speaker: Jackson Morrow of Emory University
Contact: David Zureick-Brown, DAVID.M.BROWN.JR@GMAIL.COM
Date: 2020-03-03 at 4:00PM
Venue: MSC W303
Abstract:
Title: TBA
Seminar: Algebra
Speaker: Harris Daniels of Amherst College
Contact: David Zureick-Brown, david.zureick.brown@gmail.com
Date: 2020-03-17 at 4:00PM
Venue: MSC W303
Abstract:
Title: Thesis Defense: Local-global principles for norm one tori over semi-global fields.
Seminar: Algebra
Speaker: Sumit Chandra Mishra of Emory University
Contact: David Zureick-Brown, DAVID.M.BROWN.JR@GMAIL.COM
Date: 2020-03-24 at 4:00PM
Venue: MSC W303
Abstract:
Title: Athens-Atlanta joint Number Theory Seminar
Seminar: Algebra
Speaker: Samit Dasgupta and Wei Ho of Duke University and University of Michigan
Contact: David Zureick-Brown, dzb@mathcs.emory.edu
Date: 2020-04-09 at 4:00PM
Venue: MSC W303
Abstract:
Talks will be at Emory. Abstracts to appear soon.
Title: Georgia Algebraic Geometry Seminar
Seminar: Algebra
Speaker: Various of Emory University
Contact: David Zureick-Brown, DAVID.M.BROWN.JR@GMAIL.COM
Date: 2020-04-17 at 4:00PM
Venue: MSC Other
Abstract:
The Georgia Algebraic Geometry Symposium is a conference series, jointly organized by the University of Georgia, Emory University and Georgia Tech. \\ All talks will be in Room 208 of the Mathematics and Science Center (400 Dowman Drive, Atlanta GA 30322). Registration and refreshments will be in the second floor atrium. \\ http://www.math.emory.edu/~dzb/conferences/GAGS2020/