All Seminars
| Title: Shaping your research so it can transition to practice: a view from data integration research |
|---|
| Seminar: Computer Science |
| Speaker: Arnon (Arnie) Rosenthal of MITRE |
| Contact: Li Xiong, lxiong@mathcs.emory.edu |
| Date: 2009-02-27 at 3:00PM |
| Venue: MSC W301 |
| Download Flyer |
| Abstract: Data integration technology aims to transform data from the providers’ form to a form consumers can use, and also to merge data from multiple providers. Relevant theory and algorithms appeared as early as the 1980s, but until very recently the transition to products was highly disappointing After an introduction to the challenges of data integration, we examine research areas whose results were difficult to transfer. From these, we identify two generic tactics for formulating good research problems whose theoretical results will also be exploitable by product planners and by development teams. First, if you have a theoretical results that applies to constrained, simplified problems, extend it to be /somewhat /useful on systems that violate the constraint. Second, work “downstream” first – tackle the last challenge that blocks creating runnable code with large user bases – otherwise your results may stay on the shelf for decades (e.g., schema matching circa 1985-2008). Finally, we will examine how well research has aligned with needs (i.e., areas desperately needing models and technique to clarify them. While there has been some terrific (and terrifically useful) recent research on data integration (e.g., {IBM, Microsoft, Google} Research), we will describe our pain points – terrifically important challenges for tractable research problems have not yet been formulated (let alone solved). |
| Title: Sage -- Creating a Viable Free Open Source Alternative to Magma, Maple, Mathematica, and Matlab |
|---|
| Colloquium: N16 |
| Speaker: William Stein of University of Washington |
| Contact: David Borthwick, davidb@mathcs.emory.edu |
| Date: 2009-02-27 at 4:00PM |
| Venue: MSC W201 |
| Download Flyer |
| Abstract: Do you currently run Magma, Maple, Mathematica, or Matlab? In this talk, I will take an in-depth look at Sage, which is a free open source mathematics software project that I started in 2005. Sage can be used to study general and advanced, pure and applied mathematics. This includes a huge range of mathematics, including algebra, calculus, elementary to very advanced number theory, cryptography, numerical computation, commutative algebra, group theory, combinatorics, graph theory, exact linear algebra and much more. It combines various software packages and seamlessly integrates their functionality into a common experience. It is well suited for education, studying and research. |
| Title: GL(n) Representations - Yeah Schur. |
|---|
| Seminar: Algebra |
| Speaker: Georgia Benkart of University of Wisconsin |
| Contact: Audrey Malagon, amalago@emory.edu |
| Date: 2009-02-26 at 4:00PM |
| Venue: MSC W303 |
| Download Flyer |
| Abstract: By exploiting the commuting actions of the general linear and symmetric groups, Schur was able to prove combinatorial results about such things as symmetric functions and invariants. These methods work in a variety of settings and reveal beautiful connections with diagram algebras and walks on Dynkin diagrams. |
| Title: Turan theorem: generalizations and applications |
|---|
| Colloquium: Combinatorics |
| Speaker: Benjamin Sudakov of UCLA |
| Contact: Vojtech Rodl, rodl@mathcs.emory.edu |
| Date: 2009-02-25 at 3:00PM |
| Venue: MSC W303 |
| Download Flyer |
| Abstract: In typical extremal problem one wants to determine maximum cardinality of discrete structure with certain prescribed properties. Probably the earliest such result was obtain 100 years ago by Mantel who computed the maximum number of edges in a triangle free graph on n vertices. This was generalized by Turan for all complete graphs and became a starting point of Extremal Graph Theory. In this talk we survey several classical problems and results in this area and present some interesting applications of Extremal Graph Theory to other areas of mathematics. We also describe a recent surprising generalization of Turan's theorem which was motivated by question in Computational Complexity. |
| Title: Travels to a Hyperbolic Space Starting from an sl(2) Base |
|---|
| Colloquium: Algebra |
| Speaker: Georgia Benkart of University of Wisconsin |
| Contact: Audrey Malagon, amalago@emory.edu |
| Date: 2009-02-25 at 4:00PM |
| Venue: MSC W201 |
| Download Flyer |
| Abstract: By choosing a suitable basis of the Lie algebra sl(2) of 2 x 2 matrices of trace 0, connections with the modular group, the braid group on 3 strands, Tits buildings, and hyperbolic space become readily apparent. This talk will be a trip through these topics. |
| Title: On the complexity of factoring polynomials over finite fields |
|---|
| Colloquium: N16 |
| Speaker: Kiran Kedlaya of |
| Contact: Aaron Abrams, abrams@mathcs.emory.edu |
| Date: 2009-02-24 at 4:00PM |
| Venue: MSC W201 |
| Download Flyer |
| Abstract: Abstract: While factoring large polynomials over finite fields is (apparently) far easier than factoring large integers, it is still an open problem to give an algorithm that does it ``as fast as possible'' (roughly speaking, in time proportional to the length of the input data). We will explain a recent improvement in the complexity of factoring polynomials over finite fields, based on an asymptotically optimal solution of a related problem (the modular composition problem). Joint work with Chris Umans (Caltech). |
| Title: Quantitative genetics of muscle mass loss - sarcopenia, the new epidemic in developed countries - there is no solution without mathematics |
|---|
| Chapter Talk: SIAM |
| Speaker: Gregory Livshits of Human Population Biology Research Unit, Sackler Faculty of Medicine, Tel Aviv University, Israel and Department of Twin Research and Genetic Epidemiology Division of Genetics and Molecular Medicine Ki |
| Contact: Raya Horesh, rshindm@emory.edu |
| Date: 2009-02-20 at 3:00PM |
| Venue: MSC W303 |
| Download Flyer |
| Abstract: Lean body mass (LBM) is one of the three major components of body composition, which includes also body fat (FBM) and bone mass (BBM). As the other two components it is highly important for normal physiology and metabolism, and deviations from normal values are often associated with various pathological conditions. Of these the major one is probably sarcopenia ? the age related loss of muscle mass. However, while for each of FBM and BBM, many dozens of publications concerning candidate genes, whole genome linkage and association studies were published during the last two decades, there are virtually no publications on LBM in this respect. Huge effort is now invested in creation of a large international consortium which will tackle this problem. The main aim of this talk will be twofold. One, it will be focused on the results of our genetic epidemiological study of LBM and sarcopenia in a normal human population. We present estimates of the putative genetic factors contribution and results of the whole genome linkage and association analyses. The second aim is to attract the mathematicians? attention to a number of difficult problems in which modern biology became engaged with unprecedented development of biotechnology and bioinformatics. This includes such ?classical? problems, inherited from whole genome linkage studies, as multiple testing adjustments and multiple signal combination, and relatively new problems as e.g. multiple low effect signals and their interactions and several others. |
| Title: Random Subgraphs of a Given Graph |
|---|
| Colloquium: N16 |
| Speaker: Paul Horn of The University of California, San Diego |
| Contact: Dwight Duffus, dwight@mathcs.emory.edu |
| Date: 2009-02-19 at 3:00PM |
| Venue: MSC W303 |
| Download Flyer |
| Abstract: Data from real-world graphs often contains incomplete information, so we only observe subgraphs of these graphs. It is therefore desirable to understand how a typical subgraph relates to the underlying host graph. We consider several interrelated problems involving both random trees in host graphs and random subgraphs obtained by taking edges of the host graph independently with probability p. In the second case, we study the emergence of the giant component. We also use the spectral gap to understand discrepancy and expansion properties of a random subgraph. The Erdos-Renyi random graph is the special case of this where the host graph is the complete graph Kn. Additional applications include taking a contact graph as the host graph, and viewing random subgraphs as outbreaks of a disease. |
| Title: Counting points and doing integrals on Feynman diagrams |
|---|
| N16 Colloquium: Number theory |
| Speaker: Patrick Brosnan of University of British Columbia |
| Contact: Skip Garibaldi, skip@mathcs.emory.edu |
| Date: 2009-02-19 at 4:00PM |
| Venue: MSC W303 |
| Download Flyer |
| Abstract: Let $G$ be a finite connected graph with $E$ edges. The Kirchhoff polynomial of $P(G)$ is a certain homogeneous polynomial in $E$ variables whose degree is the first Betti number of the graph. These polynomials appeared classically in the study of electrical circuits (e.g., Kirchhoff's laws). They also appear in the evaluation of Feynman integrals. Motivated by computer calculations of D.~Kreimer and D.J.~Broadhurst associating multiple zeta values to certain Feynman integrals, Kontsevich conjectured that the number of zeros of $P(G)$ over a field with $q$ elements is a polynomial function of $q$. P.~Belkale and I disproved this conjecture by relating the schemes $V(P(G))$ to the representation spaces of certain combinatorial objects called matroids. I will discuss this work and subsequent work on the number-theoretical properties of Feynman amplitudes. |
| Title: Galois Theory and Patching |
|---|
| Colloquium: N/A |
| Speaker: David Harbater of University of Pennsylvania |
| Contact: R. Parimala, parimala@mathcs.emory.edu |
| Date: 2009-02-17 at 4:00PM |
| Venue: W306 |
| Download Flyer |
| Abstract: |