Seminars and Colloquia by Series

Birth & Future of Multi-scale Modeling of Macromolecules

Series
Other Talks
Time
Monday, November 24, 2014 - 16:30 for 2.5 hours
Location
GT Student Center Ballroom
Speaker
2013 Nobel Laureate Michael LevittStanford University

Please Note: Biography: Michael Levitt is an American-British-Israeli biophysicist and professor of structural biology in the Stanford University School of Medicine and a winner of the 2013 Nobel Prize in Chemistry. Born in South Africa in 1947, Levitt earned his Bachelor of Science in Physics from Kings College London and his Ph.D. in biophysics from Cambridge University. His research involves multi-scale approaches to molecular modeling: Coarse-grained models that merge atoms to allow folding simulation and hybrid models that combine classical and quantum mechanics to explain how enzymes works by electrostatic strain. Levitt's diverse interests have included RNA and DNA modeling, protein folding simulation, classification of protein folds and protein geometry, antibody modeling, x-ray refinement, antibody humanization, side-chain geometry, torsional normal mode, molecular dynamics in solution, secondary structure prediction, aromatic hydrogen bonds, structure databases, and mass spectrometry. His Stanford research team currently works on protein evolution, the crystallographic phase problem and Cryo-EM refinement. He is a member of both the Royal Society of London and the U.S. National Academy of Science. Levitt also remains an active computer programmer--"a craft skill of which I am particularly proud," he says.

The development multiscale models for complex chemical systems began in 1967 with publications by Warshel and Levitt recently recognized by the 2013 Nobel Committee for Chemistry. The simplifications used then at the dawn of the age of computational structural biology were mandated by computers that were almost a billion times less cost-effective than those we use today. These same multiscale models have become increasingly popular in application that range from simulation of atomic protein motion, to protein folding and explanation of enzyme catalysis. In this talk I describe the origins of computational structural biology and then go on to show some of the most exciting current and future applications. Please RSVP. Reception begins at 4:30PM; lecture starts at 5:00PM.

Nonnegative curvature and pseudoisotopies

Series
Geometry Topology Seminar
Time
Monday, November 24, 2014 - 14:05 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Igor BelegradekGeorgia Tech
I will sketch how to detect nontrivial higher homotopy groups of the space of complete nonnegatively curved metrics on an open manifold.

Quadratic points on hyperelliptic curves

Series
Algebra Seminar
Time
Friday, November 21, 2014 - 15:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Jennifer ParkMcGill University
Using the ideas of Poonen and Stoll, we develop a modified version of Chabauty's method, which shows that a positive proportion of hyperelliptic curves have as few quadratic points as possible.

Embeddings of manifolds and contact manifolds VI

Series
Geometry Topology Working Seminar
Time
Friday, November 21, 2014 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
John EtnyreGeorgia Tech
This is the sixth (and last) of several talks discussing embeddings of manifolds. I will discuss some general results for smooth manifolds, but focus on embeddings of contact manifolds into other contact manifolds. Particular attention will be paid to embeddings of contact 3-manifolds in contact 5-manifolds. I will discuss two approaches to this last problem that are being developed jointly with Yanki Lekili.

Singularity formation in Compressible Euler equations (Part IV)

Series
PDE Working Seminar
Time
Thursday, November 20, 2014 - 15:00 for 1 hour (actually 50 minutes)
Location
Skiles 005
Speaker
Ronghua PanGeorgiaTech
Compressible Euler equations describe the motion of compressible inviscid fluid. Physically, it states the basic conservation laws of mass, momentum, and energy. As one of the most important examples of nonlinear hyperbolic conservation laws, it is well-known that singularity will form in the solutions of Compressible Euler equations even with small smooth initial data. This talk will discuss some classical results in this direction, including some most recent results for the problem with large initial data.

Effective Chabauty for symmetric powers of curves

Series
Algebra Seminar
Time
Wednesday, November 19, 2014 - 15:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Jennifer ParkMcGill University
Faltings' theorem states that curves of genus g> 1 have finitely many rational points. Using the ideas of Faltings, Mumford, Parshin and Raynaud, one obtains an upper bound on the number of rational points, but this bound is too large to be used in any reasonable sense. In 1985, Coleman showed that Chabauty's method, which works when the Mordell-Weil rank of the Jacobian of the curve is smaller than g, can be used to give a good effective bound on the number of rational points of curves of genus g > 1. We draw ideas from nonarchimedean geometry and tropical geometry to show that we can also give an effective bound on the number of rational points outside of the special set of the d-th symmetric power of X, where X is a curve of genus g > d, when the Mordell-Weil rank of the Jacobian of the curve is at most g-d.

Mutliparameter singular integrals

Series
Analysis Seminar
Time
Wednesday, November 19, 2014 - 14:00 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Brian StreetUniversity of Wisconsin, Madison
This talk concerns a theory of "multiparameter singularintegrals." The Calderon-Zygmund theory of singular integrals is a welldeveloped and general theory of singular integrals--in it, singularintegrals are associated to an underlying family of "balls" B(x,r) on theambient space. We talk about generalizations where these balls depend onmore than one "radius" parameter B(x,r_1,r_2,\ldots, r_k). Thesegeneralizations contain the classical "product theory" of singularintegrals as well as the well-studied "flag kernels," but also include moregeneral examples. Depending on the assumptions one places on the balls,different aspects of the Calderon-Zygmund theory generalize.

Dehn-Nielsen-Baer Theorem

Series
Geometry Topology Student Seminar
Time
Wednesday, November 19, 2014 - 02:01 for 1 hour (actually 50 minutes)
Location
Skiles 006
Speaker
Elizabeth BolducGeorgia Tech
The Dehn Nielsen Baer Theorem states that the extended mapping class group is isomorphic to the outer automorphisms of π1(Sg). The theorem highlights the connection between the topological invariant of distinct symmetries of a space and its fundamental group. This talk will incorporate ideas from algebra, topology, and hyperbolic geometry!

Pages