MSCS Seminar Calendar

Monday March 3, 2014
Geometry, Topology and Dynamics Seminar
Elliptic Actions on Teichmüller Space
Matthew Durham (UIC)
3:00 PM in SEO 636
Kerckhoff's solution to the Nielsen realization problem showed that the action of any finite subgroup of the mapping class group on Teichmüller space has a fixed point. The set of fixed points is a totally geodesic submanifold. We study the coarse geometry of the set of points which have bounded diameter orbits in the Teichmüller metric. We show that each such almost-fixed point is within a uniformly bounded distance of the fixed point set, but that the set of almost-fixed points is not quasiconvex. In addition, the orbit of any point is shown to have a fixed barycenter. In this talk, I will discuss the machinery and ideas used in the proofs of these theorems.

Applied Mathematics Seminar
On decay properties of solutions of the $k$-generalized KdV equation
Felipe Linares (IMPA Brasil)
4:00 PM in SEO 636
In this talk I will describe recent results regarding special decay properties of solutions to the initial value problem associated to the $k$-generalized Korteweg-de Vries equation. These are related with persistence properties of the solution flow in weighted Sobolev spaces and with sharp unique continuation properties of solutions to this equation. If time allows I will talk on recent extensions of some of the results above for higher order dispersive equations.
Tuesday March 4, 2014
Quantum Topology / Hopf Algebra Seminar
Some recent results on coloring of knots.
Jun Ge (UIC)
3:00 PM in SEO 612
In this talk, we will mainly focus on some recent results about the minimum number of colors.

Graduate Statistics Seminar
On pseudo-Bayesian inference via fractional likelihood
Ryan Martin (UIC)
3:30 PM in SEO 1227
Bayes's theorem provides the tool for combining prior beliefs with evidence from data, and there are general sufficient conditions that guarantee the corresponding Bayesian posterior distribution will be consistent, i.e., will concentrate around the true parameter asymptotically. Non-trivial examples of inconsistent posterior distributions are scarce, so it's not clear if the existing sufficient conditions are the right things. Towards understanding what it takes for posterior consistency, I will show that by making a minor adjustment to the formula of Bayes, namely, taking an arbitrary fractional power on the likelihood before combining with the prior, will avoid all known non-trivial examples of inconsistency. That is, the corresponding pseudo-Bayes posterior based on the fractional likelihood is, in a certain sense, always consistent. The key question is: how to make use of this interesting phenomenon? I will discuss some possible answers.

Logic Seminar
A general van der Corput lemma and underlying Ramsey theory
Anush Tserunyan (UIUC)
4:00 PM in SEO 427
A major theme in ergodic Ramsey theory and multiplicative combinatorics is proving multiple recurrence results for certian doubly recurrent (mixing) actions of semigroups. The amplification of double to multiple recurrence is usually done using a so-called van der Corput difference (ratio) lemma for a suitable filter on the semigroup. Particular instances of this lemma (for concrete filters) have been known proven before (by Furstenberg, Bergelson-McCutcheon, and others), with a different proof for each filter. We define a general class of filters on semigroups, which includes all of the filters for which the van der Corput lemma was known. For the filters in this class (call them Delta-filters), we prove a Ramsey theorem related to labeling edges between the semigroup elements with their ratios. An application of this theorem yields a van der Corput lemma for Delta-filters, generalizing all its previous instances.

Mathematics Education Colloquium
Deepening our Knowledge of Students' Mathematical Thinking Processes through a Purposeful Pedagogy Model of Instruction
Laura Kent (University of Arkansas)
5:00 PM in SEO 636
Cognitively Guided Instruction (CGI) and Extending Children's Mathematics (ECM) professional development programs are specifically designed to enhance teachers' knowledge of students' thinking about mathematics. Detailed explorations of problem type taxonomies and strategy frameworks are pivotal aspects of the professional development and help teachers focus and build instruction on students' conceptual understandings of number concepts, ranging from whole number to rational number topics. Examples of the "Purposeful Pedagogy" model related to teaching fraction concepts for understanding from the newly created ECM program will be highlighted.
Light refreshments will be available.
Wednesday March 5, 2014
Graduate Geometry, Topology and Dynamics Seminar
Mamikon's Theorem and Applications
Josh Faber (UIC)
3:00 PM in SEO 612

Algebraic Geometry Seminar
Extremal degenerations of Hodge structure
Colleen Robles (IAS/Texas A&M)
3:00 PM in SEO 636
I will describe a program to formulate and answer in a well-posed manner the question: what are the extremal degenerations of a smooth variety? That is, what is the least singular' variety X can degenerate to? and what is the most singular' variety X can degenerate to? These and related questions are being investigated, in various subsets of collaboration, by Mark Green, Phillip Griffiths, Matt Kerr, Greg Pearlstein and myself.

Distinguished Lecture Series
Invariants as the engine for mathematics
Michael Hopkins (Harvard University)
4:00 PM in BSB 250
In mathematics and in science an "invariant" of a system is a quantity, like the total energy, that does not change as the system evolves. The discovery and understanding of invariants is a significant part of what drives the development of mathematics. In this talk I will describe some simple mathematical invariants and the deep mathematics that has evolved from trying to understand them.
The general public is invited. Reception to follow.
Thursday March 6, 2014
Louise Hay Logic Seminar
Morley's Analysis of Countable Models
Jonathan Wolf (UIC)
3:00 PM in SEO 427

Graduate Number Theory Seminar
Overview of the analogy between number fields and function fields
Joseph Berner (UIC)
3:00 PM in SEO 512
We will give an example driven overview of the analogy between number fields and function fields of curves over finite fields. This will naturally lead us to discuss the analogy between rings of integers of number fields and affine curves over finite fields. If time permits we may discuss more complex invariants and how they compare.

Distinguished Lecture Series
The Kervaire Invariant
Michael Hopkins (Harvard University)
4:00 PM in LCD 005
The Kervaire invariant is subtle and important invariant lying at the interface of algebraic and differential topology. I will describe the history of this invariant, the problem it raised, and its eventual solution.
Friday March 7, 2014
Departmental Colloquium
Distinguished Lecture Series
Michael Hopkins (Harvard University)
3:00 PM in LC D5
http://www.math.uic.edu/seminars/poster?seminar_id=3027
Distinguished Lecture Series in Lecture Center D5

Distinguished Lecture Series
Chern-Weil invariants and abstract homotopy theory
Michael Hopkins (Harvard University)
3:00 PM in LCD 005
Nature does not come to us with a coordinate system. In writing down the equations describing the evolution of physical systems, it is therefore important that the mathematical entities that arise do not depend on a choice of coordinates. The Chern-Weil invariants are important examples of such entities. In this talk I will explain the Chern-Weil invariants and how one is led by by thinking carefully about them to modern day abstract homotopy theory.
This is also the Department Colloquium this week; note the different room (LCD 005, not the usual SEO 636). Tea in SEO 300 at 4:15pm.
Monday March 10, 2014
Geometry, Topology and Dynamics Seminar
TBA
Yair Glasner (Ben Gurion University, and University of Utah)
3:00 PM in SEO 636
TBA

Applied Mathematics Seminar
Vortex stretching and anisotropic diffusion in the 3D NSE
Zoran Grujic (University of Virginia)
4:00 PM in SEO 636
The purpose of this lecture is to present a physically, numerically, and mathematical analysis-motivated scenario in which the transversal small scales produced by the mechanism of vortex stretching reach the threshold sufficient for the locally anisotropic diffusion to engage and control the sup-norm of the vorticity, preventing possible formation of singularities in the 3D Navier-Stokes flows.
Tuesday March 11, 2014
Quantum Topology / Hopf Algebra Seminar
Introducing Real Algebraic Geometry
Jim Otto (UIC)
3:00 PM in SEO 612
We will begin to consider Real Algebraic Geometry following the '98 Springer book of that name by Bochnak, Coste, and Roy. In particular, we will consider Real Spectrum.

Algebraic Geometry Seminar
Introduction to singularities in algebraic geometry
Shihoko Ishii (University of Tokyo)
3:00 PM in SEO 712

Logic Seminar
Ultraproducts of Quasirandom Graphs and Hypergraphs
Henry Towsner (University of Pennsylvania)
4:00 PM in SEO 427
The many equivalent characterizations of quasirandomness for graphs have been extensively studied. When generalized to hypergraphs, these notions split into a partially ordered family of distinct notions, recently shown by Lenz and Mubayi to not even be linearly ordered.
The ultraproduct setting, equipped with Loeb measure, turns out to be a natural place to examine these notions; in this setting, the different notions of quasirandomness for hypergraphs match up to certain natural algebras of definable sets. Considering all possible variations of these algebras includes all the notions studied so far, and introduces a few new notions. For some characterizations of graph randomness we are able to produce a generalization corresponding to each possible algebra. In particular, for each algebra we identify the class of hypergraphs which appear with the "correct" frequency in any hypergraph random for that algebra.

Graduate Teaching of Mathematics Seminar
Written Summaries in Calculus 3
Jessica Dyer (UIC)
4:30 PM in SEO 1227
Wednesday March 12, 2014
Computer Science Seminar
An optimal scheduling problem for actions on the nodes of a graph
Alexander Gutfraind (UIC Epidemiology and Biostatistics)
3:00 PM in SEO 427
Complex networks are frequently used to model natural, social, and engineered systems. Many studies looked at the problem of modeling the topology of a network or designing it but less is known, even in a stylized form, about how one might optimally install a given network topology, assuming that installing a node aids the installation of neighboring nodes. This problem arises in engineering when, after a disaster, damaged infrastructure networks are to be recovered. We introduce a new discrete optimization problem where the goal is to minimize the total cost of installing a given network. This cost is determined by the structure of the network and the schedule with which the nodes are installed. Namely, the cost of installing a node is a function of the number of its neighbors that have been installed before it. We analyze the common case where the cost function is decreasing and convex, and provide bounds on the cost of the optimal solution. We also show that all sequences have the same cost when the cost function is linear and give results on the cost of a random solution for several models of random graphs. Examining the computational complexity, we show that the problem is NP-hard when the cost function is arbitrary. Finally, we provide an integer program, a dynamic programming algorithm, and greedy heuristics that give high quality solutions.
This is joint work with Milan Bradonjic and Tim Novikoff.

Statistics Seminar
TBA
Prof. Annie Qu (UIUC)
4:00 PM in SEO 636

Algebraic Geometry Seminar
Stable Quotients in Low Genus
Yaim Cooper (Harvard University)
4:00 PM in SEO 427
Stable quotient spaces provide an alternative to stable maps for compactifying spaces of maps. In this talk I will discuss spaces of stable quotients which compactify the space of degree $d$ maps of genus $g$ curves to $P^n$. I will describe what is known about the geometry of these spaces. I will also discuss the relationship between these spaces and the corresponding spaces of stable maps from the perspective of mirror symmetry and the perspective of the minimal model program.
Thursday March 13, 2014
Graduate Number Theory Seminar
TBA
Cara Mullen (UIC)
3:00 PM in SEO 512

Louise Hay Logic Seminar
TBA
Bruno de Mendonca Braga (UIC)
3:00 PM in SEO 427

Graduate Student Colloquium
Introduction to Teichmuller space, the mapping class group, and the curve complex
Yen Duong (UIC)
4:00 PM in SEO 636
This is the first of a series of two talks. This will provide the motivation and definitions for the next talk. There'll be algebra and pictures and definitions of the three things in the title. No background is assumed (you should know what a quotient group is, I guess).

Algebraic Geometry Seminar
Introduction to singularities in algebraic geometry
Shihoko Ishii (Univesity of Tokyo)
4:00 PM in SEO 712
Friday March 14, 2014
Departmental Colloquium
Graduate Recruitment Day
TBA (TBA)
3:00 PM in SEO 636
TBA
Monday March 17, 2014
Geometry, Topology and Dynamics Seminar
TBA
Jing Tao (University of Oklahoma)
3:00 PM in SEO 636
TBA

Applied Mathematics Seminar
TBA
Benjamin Gess (University of Chicago)
4:00 PM in SEO 636
Tuesday March 18, 2014
Logic Seminar
TBA
Philipp Hieronymi (UIUC)
4:00 PM in SEO 427
Wednesday March 19, 2014
Combinatorics Seminar
From Graphs to Simplicial Complexes: Isoperimetric Constants, Random Walks, and the Hodge Laplacian
John Steenbergen (UIC)
3:00 PM in SEO 427
Isoperimetric constants and random walks have played an important role in the study of spectral graph theory and its applications, like clustering and partially-labelled classification. In this talk, we present new types of isoperimetric constants and random walks on simplicial complexes which generalize to higher dimensions their classical counterparts on graphs. Of particular interest is how these relate to the spectrum of the combinatorial Hodge Laplacian. Various results will be presented which shed light on the spectral gap and what it means for a simplicial complex to "almost" have a nontrivial homology class. Higher-dimensional analogues of clustering and partially-labelled classification will also be discussed.

Statistics Seminar
Predicting Right Score Distributions from Data Collected under Formula Score Instructions
Dr. Hongwen Guo (ETS)
4:00 PM in SEO 636
Under formula score instruction (FSI), test takers may omit items instead of guessing. If the students are required to answer every items (under the rights only scoring instruction, ROI), the score distribution will be different. In this study, we tried to model the data using a simple statistical model and provide a formula to predict the score distribution under ROI based on the score distribution and the omit rate observed under FSI. A preliminary investigation of the guessing parameter is presented in the paper. Based on the data used in the study, the guessing parameter may be close or slightly lower than the chance score.

Algebraic Geometry Seminar
On subadditivity of Kodaira dimension in positive characteristic
Zsolt Patakfalvi (Princeton University)
4:00 PM in SEO 427
Kodaira dimension is a fundamental (if not the most fundamental) birational invariant of an algebraic variety. It assigns a number between 0 and the dimension or negative infinity to every birational equivalence class of varieties. The bigger this number is the more the variety is thought of as being "hyperbolic". Subadditivity of Kodaira dimension is a conjecture of Iitaka stating that for an algebraic fiber space f : X -> Y, the Kodaira dimension of the total space is at least as big as the sum of the Kodaira dimensions of the geometric generic fiber and the base. I will present a positive answer to this conjecture over an algebraically closed field of positive characteristic, when Y is of general type, f is separable and the Hasse-Witt matrix of the geometric generic fiber is not nilpotent.
Thursday March 20, 2014
Louise Hay Logic Seminar
Classification Theory for Accessible Categories
Michael Lieberman (Kalamazoo College)
3:00 PM in SEO 427
We discuss recent joint work with Jiri Rosicky which seeks to extend a fragment of the classification theory of AECs to the more general framework of accessible categories, particularly for accessible categories with directed colimits: essentially AECs minus coherence. There are several pleasant surprises---a generalization of Boney's recent theorem on tameness under a large cardinal hypothesis follows from work of Makkai and Pare, and these categories admit a robust Ehrenfeucht-Mostowski functor which can be used to mimic certain constructions in AECs. On the other hand, this investigation also illuminates the areas and arguments where coherence is indispensable...
Friday March 21, 2014
Departmental Colloquium
TBA
Rakesh Vohra (University of Pennsylvania)
3:00 PM in SEO 636
Monday March 31, 2014
Geometry, Topology and Dynamics Seminar
TBA
Lucas Culler (MIT)
3:00 PM in SEO 636

Applied Mathematics Seminar
The structure of pullback attractors for the 3D Navier-Stokes Equations.
Landon Kavlie (University of Illinois Chicago)
4:00 PM in SEO 636
Tuesday April 1, 2014
Logic Seminar
TBA
Isaac Goldbring (UIC)
4:00 PM in SEO 427
Wednesday April 2, 2014
Combinatorics Seminar
Packing k-partite k-graphs
Richard Mycroft (Birmingham)
3:00 PM in SEO 427
Let G and H be graphs or hypergraphs. A perfect H-packing in G is a collection of vertex-disjoint copies of H in G which together cover every vertex of G. In the simplest case, where H is the graph consisting of a single edge, a perfect H-packing in G is simply a perfect matching in G; Dirac's theorem tells us that such a packing must exist if G has minimum degree at least n/2 (where n is the number of vertices of G). The problem of what minimum degree is needed to ensure a perfect H-packing in G for general graphs H was then tackled by many researchers, before K\"uhn and Osthus finally established the correct threshold for all graphs H (up to an additive constant).
However, for k-uniform hypergraphs (or k-graphs) much less is known. The case of a perfect matching has been well-studied, but apart from this there were previously no known asymptotically correct results on the minimum degree needed to ensure a perfect H-packing in G for k > 4 (for any of the various common generalisations of the notion of degree to the k-graph setting).
In this talk I will demonstrate, for any complete k-partite k-graph H, the asymptotically best-possible minimum codegree condition for a k-graph G which ensures that G contains a perfect H-packing. This condition depends on the sizes of the vertex classes of H, and whether these sizes, or their differences, share any common factors greater than one.

Statistics Seminar
TBA
Prof. Bikas Sinha (Indian Institute of Statistics)
4:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Yi Zhu (University of Utah)
4:00 PM in SEO 427
Thursday April 3, 2014
Louise Hay Logic Seminar
TBA
Jin Du (UIC)
3:00 PM in SEO 427
Friday April 4, 2014
Departmental Colloquium
TBA
Matthew Foreman (UC Irvine)
3:00 PM in SEO 636
Monday April 7, 2014
Geometry, Topology and Dynamics Seminar
TBA
Jeremy Tyson (Univ. of Illinois Urbana-Champaign)
3:00 PM in SEO 636
Tuesday April 8, 2014
Graduate Statistics Seminar
Introduction to Item Response Theory and Differential Item Functioning I
Ken Fujimoto (UIC)
3:30 PM in SEO 636
Wednesday April 9, 2014
Statistics Seminar
TBA
Paul Livermore Auer (University of Wisconsin at Milwaukee)
4:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Chunyi Li (UIUC)
4:00 PM in SEO 427
Friday April 11, 2014
Departmental Colloquium
TBA
Douglas Arnold (University of Minnesota)
3:00 PM in SEO 636
Monday April 14, 2014
Geometry, Topology and Dynamics Seminar
TBA
Tarik Aougab (Yale University)
3:00 PM in SEO 636

Applied Mathematics Seminar
TBA
Min Chen (Purdue)
4:00 PM in SEO 636
Tuesday April 15, 2014
Graduate Statistics Seminar
Introduction to Item Response Theory and Differential Item Functioning II
Ken Fujimoto (UIC)
3:30 PM in SEO 636

Logic Seminar
TBA
Dima Sinapova (UIC)
4:00 PM in SEO 427
Wednesday April 16, 2014
Geometry, Topology and Dynamics Seminar
TBA
Pierre-Emmanuel Caprace (Universite catholique de Louvain)
3:00 PM in SEO 612

Algebraic Geometry Seminar
TBA
Giulia Sacca (Stony Brook)
4:00 PM in SEO 427

Statistics Seminar
Recent developments in optimal experimental designs for functional MRI
Prof. Ming-Hung (Jason) Kao (Arizona State University)
4:00 PM in SEO 636
Functional magnetic resonance imaging (fMRI) is one of the leading brain mapping technologies for studying brain activity in response to mental stimuli. For neuroimaging studies utilizing this pioneering technology, there is a great demand of high-quality experimental designs that help to collect informative data to make precise and valid inference about brain functions. In this talk, I briefly introduce some recently developed analytical and computational results on fMRI experimental designs. The performance of some commonly considered designs such as m-sequences is discussed. In addition, a new type of fMRI designs that are constructed using a certain type of Hadamard matrices is also discussed. Under certain assumptions, these designs can be shown to be optimal in some statistically meaningful sense. Some possible future research directions are also presented.
Friday April 18, 2014
Algebraic Geometry Seminar
TBA
Rahul Pandharipande (ETH Zurich)
4:00 PM in SEO 427
Monday April 21, 2014
Applied Mathematics Seminar
TBA
Maria Schonbek (University of California, Santa Cruz)
4:00 PM in SEO 636
Tuesday April 22, 2014
Graduate Statistics Seminar
Integrative network analysis of TCGA data for ovarian cancer
Qingyang Zhang (Northwestern)
3:30 PM in SEO 636
Traditional cancer studies have been mainly focusing on single gene or single type of data including mRNA expression, DNA methylation, copy number variation, and etc. However, such analyses lack power to reveal the molecular mechanisms from the view of system biology. In this talk, I will present an integrative framework to identify important genetic and epigenetic features and to quantify the causal relations among these features. I will first talk about what is a Bayesian Network and what the TCGA data looks like. Then I will introduce the proposed feature selector and Bayesian Network model. Simulated and real data sets will be used for illustration.

Logic Seminar
TBA
Itay Neeman (UCLA)
4:00 PM in SEO 427
Wednesday April 23, 2014
Statistics Seminar
TBA
Prof. Tony Sun (University of Missouri)
4:00 PM in SEO 636
TBA

Algebraic Geometry Seminar
TBA
Noah Giansiracusa (UC Berkeley)
4:00 PM in SEO 427
Friday April 25, 2014
Departmental Colloquium
TBA
Mircea Mustata (University of Michigan)
3:00 PM in SEO 636
Tuesday April 29, 2014
Graduate Statistics Seminar
TBA
Jing Wang (UIC)
3:30 PM in SEO 636

Logic Seminar
TBA
Slawomir Solecki (UIUC)
4:00 PM in SEO 427
Wednesday April 30, 2014
Statistics Seminar
TBA
Dr. Devanarayan Viswanath (Abbive)
4:00 PM in SEO 636
Friday May 2, 2014
Departmental Colloquium
Atkin Memorial Lecture
Showu Zhang (Princeton University)
3:00 PM in TBA
The talk is followed by reception, dinner, and a workshop on Saturday and Sunday. Details to follow.
UIC LAS MSCS seminars seminar calendar