# MSCS Seminar Calendar

Monday September 22, 2014
Model Theory Seminar
Quasiminimality and Excellence I
Will Boney (UIC)
1:00 PM in SEO 427
We begin discussion of the paper Quasiminimal structure and excellence by Bays, Hart, Hyttinen, Kesala and Kirby.

Computer Science Seminar
Fuzzy operators for practical applications
Jozsef Dombi (University of Szeged)
3:00 PM in SEO 427
In the first part we study a certain class of strict monotone fuzzy operators which build the DeMorgan class with infinitely many negations. We give a necessary and sufficient condition for an operator to belong to this class. We give a new representation theorem of negation based on the generator function of the strict operator.
On the other hand our starting point is the study of the relationship for Dombi aggregative operators, uninorms, strict t-norms and t-conorms. We present a new representation theorem of strong negations where two explicitly contain the neutral value. Then relationships for aggregative operators and strong negations are verified as well as those for t-norm and t-conorm using the Pan operator concept. We will study a certain class of aggregative operators which build a self-DeMorgan class with infinitely many negation operators. We introduce the so-called Pliant concept and characterize it by necessary and sufficient conditions.
In the second part we give a certain class of weighted aggregative operators (weighted representable uninorms). After that, we focus on a specific form of the aggregative operator. Using Dombi's generator function, we show that this form is the same as that for the aggregation of expert probability values, and we can get this operator via Bayes' theorem. These two theorems shed new light on the class of aggregative operators.

TBA
Joseph Berner (UIC)
3:00 PM in SEO 712

Geometry, Topology and Dynamics Seminar
Transitivity degrees of countable groups.
Michael Hull (UIC)
3:00 PM in SEO 636
We introduce the transitivity degree of a countable group $G$, denoted $td(G)$, as the $\sup$ over all $k$ such that $G$ admits a faithful, $k$-transitive action on an set with at least k elements. We show that for many classes of infinite groups (e.g. hyperbolic groups, mapping class groups, 3-manifold groups, RAAGS, or any infinite subgroups of one of these), $td(G)\in\{1, \infty\}$. In particular, we show that if $G$ is acylindrically hyperbolic and $G$ has no finite normal subgroups, $G$ admits a faithful action which is highly transitive, that is $k$-transitive for all $k$. We will also mention some applications of this result to the universal theory of acylindrically hyperbolic groups.

Applied Mathematics Seminar
Soft metrics for decision analysis under uncertainty
Michelle Quirk (National Intelligence University and National Geospatial-Intelligence Agency)
4:00 PM in SEO 636
Modern decision making challenges the human capacity to reason in an environment of uncertainty, imprecision, and incompleteness of information. Probability measures are not well-suited when the evidence is scarce and unreliable. Built from fuzzy sets, possibility metrics overcomes some of the restrictions and insufficiencies of probabilities, in a complementary, yet not competitive manner. We show the theoretical foundation and the interdisciplinary approach required to devise soft metrics as attributes of decision criteria that cannot be expressed numerically. This talk concludes with an example of soft metrics used in real-world ranking exercises.
Tuesday September 23, 2014
Number Theory Seminar
TBA
Ali Rajaei
11:00 AM in SEO 636
The seminar ends at 12:30.

Logic Seminar
The complexity of the homeomorphism relation between compact metric spaces
Joseph Zielinski (UIC)
4:00 PM in SEO 427
We consider the analysis of classification problems in the context of Borel reducibility and outline a proof that the complexity of the homeomorphism relation between compact metric spaces coincides, in this way, with that of the complete orbit equivalence relation of Polish group actions.
Wednesday September 24, 2014
Singularities of Schubert varieties in Grassmannians
2:00 PM in SEO 712
Schubert varieties have well understood singularities, in particular an explicit description can be given using a number of different approaches. In this talk I will give a description of the singular loci of Schubert varieties in Grassmannians using two different arguments: One uses the Bott-Samelson resolution, the other gives a description of their tangent spaces.

Graduate Geometry, Topology and Dynamics Seminar
Marshall Hall's Theorem
Joshua Marcel Lane Faber
3:00 PM in SEO 612
In this talk I will discuss the proof of Marshall Hall's Theorem from the now classic John R. Stallings' "Topology of Finite Graphs".

Roth's Theorem via the Szemeredi Regularity Lemma Part II
Caroline Terry (UIC)
4:00 PM in SEO 512
Roth's theorem states that any set of positive integers of positive upper density contains an arithmetic progression of length three. We will introduce the Szemeredi regularity lemma, then present a proof Roth's theorem which uses the regularity lemma.

Statistics Seminar
Brownian motion on manifolds
Jennifer Pajda-Delao (UIC)
4:00 PM in SEO 636
I will give some interesting estimates of Brownian motion on manifolds, including exit time estimates from a geodesic ball.

Algebraic Geometry Seminar
Kernels of numerical pushforwards
Mihai Fulger (Princeton)
4:00 PM in SEO 427
If $\pi:X\to Y$ is a morphism of projective varieties over an algebraically closed field, and $Z$ is an effective $k$-cycle on $X$, then $\pi_*Z=0$ iff $Z$ is a combination of subvarieties of $X$ that are contracted by $\pi$. When working not with cycles, but with cycle classes (modulo numerical equivalence), it is natural to ask when can we expect a similar geometric conclusion given the vanishing of a class $\pi_*\alpha$. I will present progress on this question, in particular leading to new cases of two conjectures essentially due to Debarre, Jiang, and Voisin. This is joint work with B. Lehmann.
Friday September 26, 2014
Departmental Colloquium
Weyl's asymptotic law for Lévy processes
Rodrigo Bañuelos (Purdue University)
3:00 PM in SEO 636
In October 1910 Hendrik Antoon Lorentz, 1902 Nobel Prize in Physics, delivered a series of six lectures (the Paul Wolfskehl Lectures) to the faculty of the University of Göttingen titled "old and new problems in physics." During the fourth lecture, with David Hilbert and his student Hermann Weyl present in the audience, he conjectured that the number of eigenvalues for the Laplacian for a region $D$ in three space not exceeding the positive number $\lambda$ is proportional to the volume of $D$ times $\lambda^{3/2}$, when $\lambda$ is large. (The problem had been raised a month earlier by Arnold Sommerfeld at a lecture in Könisberg.) Hilbert predicted that the conjecture would not be proved in his lifetime. He was wrong by several years. The conjecture was proved by Weyl in 1912.
Weyl's celebrated theorem, commonly referred to as Weyl's Law, has been extended and refined in many directions with connections to many areas of mathematics and physics. In this talk we first give an overview of some of the classical results in the field and discuss the elegant connections to Brownian motion first explored by Mark Kac in the 50's and 60's. We will then discuss problems that arise when the Brownian motion, which "goes" with the classical Laplacian, is replaced by other Lévy processes. Such processes share many important properties with Brownian motion. We will look at a class of interesting examples that have been widely studied recently, the rotationally invariant stable processes that "go" with fractional powers of the Laplacian.
Note: This is a general talk aimed at a general mathematical audience.
Monday September 29, 2014
Mean field limits of interacting Bose gases and nonlinear Schroedinger equations
Thomas Chen (UT Austin)
3:00 PM in TBA
In this talk, we survey some of the background and recent developments in the mathematical analysis of dilute Bose gases and Bose-Einstein condensation. In particular, we will address the rigorous derivation of nonlinear Schroedinger equations from manybody bosonic quantum systems in a suitable mean field limit. This presentation is geared towards a graduate student audience.

Applied Mathematics Seminar
Unconditional uniqueness for Gross-Pitaevskii hierarchies and the quantum de Finetti theorem
Thomas Chen (University of Texas at Austin)
4:00 PM in SEO 636
This talk addresses some recent results related to the Cauchy problem for the cubic Gross-Pitaevskii (GP) hierarchy, an infinite system of coupled linear PDE’s which emerges in the derivation of the cubic nonlinear Schroedinger equation from interacting Bose gases. In particular, a new proof of unconditional uniqueness of solutions is presented, as well as a proof of scattering in the defocusing 3D case. The techniques involved include an application of the quantum de Finetti theorem, combined with recursive Strichartz estimates and tree graph expansions. This is joint work with C. Hainzl, N. Pavlovic and R. Seiringer.
Wednesday October 1, 2014
Statistics Seminar
TBA
Ruoting Gong (IIT)
4:00 PM in SEO 636
Friday October 3, 2014
Departmental Colloquium
Roots, Schottky semigroups, and a proof of Bandt's Conjecture
Danny Calegari (University of Chicago)
3:00 PM in SEO 636
In 1985, Barnsley and Harrington defined a "Mandelbrot Set" M for pairs of similarities - this is the set of complex numbers z with norm less than 1 for which the limit set of the semigroup generated by the similarities x → zx and x → z(x-1)+1 is connected. Equivalently, M is the closure of the set of roots of polynomials with coefficients in {-1,0,1}. Barnsley and Harrington already noted the (numerically apparent) existence of infinitely many small "holes" in M, and conjectured that these holes were genuine. These holes are very interesting, since they are "exotic" components of the space of (2 generator) Schottky semigroups. The existence of at least one hole was rigorously confirmed by Bandt in 2002, but his methods were not strong enough to show the existence of infinitely many holes; one difficulty with his approach was that he was not able to understand the interior points of M, and on the basis of numerical evidence he conjectured that the interior points are dense away from the real axis. We introduce the technique of *traps* to construct and certify interior points of M, and use them to prove Bandt's Conjecture. Furthermore, our techniques let us certify the existence of infinitely many holes in M. This is joint work with Sarah Koch and Alden Walker.
Monday October 6, 2014
Geometry, Topology and Dynamics Seminar
Hausdorff dimension in graph matchbox manifolds
Olga Lukina (UIC)
3:00 PM in SEO 636
A lamination is a compact connected metric space, where each point has a neighborhood homeomorphic to the product of a Euclidean disc and a totally disconnected space. Given a lamination, one can ask if this lamination can be realised as a subset of a smooth foliated finite-dimensional manifold, so that the leaves of the lamination are contained in the leaves of the foliation of the manifold. More precisely, one asks if there exists a foliated embedding of a given lamination into a smooth foliated manifold by a bi-Lipschitz homeomorphism.
Hausdorff dimension provides an obstruction to the existence of such an embedding. In the talk, we study a specific class of laminations, called graph matchbox manifolds, obtained as suspensions of pseudogroup actions on the space of pointed trees. We give examples of such laminations which have infinite Hausdorff dimension of their transversals, and, therefore, cannot be embedded as a subset of a smooth foliation of a finite-dimensional manifold by a bi-Lipschitz homeomorphism.

Applied Mathematics Seminar
Kinematical Conservation Laws and Huygens’ and Fermat’s Methods of Wavefront Construction
Phoolan Prasad (Indian Institute of Science, Bangalore)
4:00 PM in SEO 636
Tuesday October 7, 2014
Logic Seminar
Regular cross-sections of Borel flows
Kostya Slutskyy (UIC)
4:00 PM in SEO 427
A cross-section of a Borel flow is a Borel set that has countable intersection with each orbit of the flow. We shall be interested in constructing cross-sections with a prescribed set of possible distances between adjacent points within orbits. The main result of the talk is that given any two rationally independent positive reals and a free Borel flow one can always find a cross-section with distances between adjacent points being only these two real numbers.
We shall give an overview of the subject from both ergodic theoretical and descriptive points of view and an application of the above result to orbit equivalence of flows will be presented.
Wednesday October 8, 2014
Statistics Seminar
Mock Oral Exam
4:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Jarek Bucynzki (Institute of Mathematics, Polish Academy of Sciences)
4:00 PM in SEO 427
Monday October 13, 2014
On Gross-Pitaevskii equations and semiclassical asymptotics
Florian Mehats (University of Rennes)
3:00 PM in TBA

Geometry, Topology and Dynamics Seminar
Coarse entropy and transverse dimension
Steve Hurder (UIC)
3:00 PM in SEO 636
The notion of "coarse entropy" for complete metric spaces was introduced in the paper "Manifolds which cannot be leaves of foliations", Topology, 1996, by O. Attie and S. Hurder, where this invariant was used to construct examples of complete Riemannian manifolds of bounded geometry which are not quasi-isometric to a leaf of any $C^1$-foliation of a closed Riemannian manifold. In this talk, we relate the coarse entropy to the "complexity entropy" of trees of finite type. We also show how the coarse entropy is related to the Hausdorff dimension of graph matchbox manifolds formed from such trees, as studied by Lukina. This work is joint with Olga Lukina.

Applied Mathematics Seminar
Dimension reduction for anisotropic Bose-Einstein condensates in the strong interaction regime
Florian Mehats (University of Rennes)
4:00 PM in SEO 636
We study the problem of dimension reduction for the three dimensional Gross-Pitaevskii equation (GPE) describing a Bose-Einstein condensate confined in a strongly anisotropic harmonic trap. Since the gas is assumed to be in a strong interaction regime, we have to analyze two combined singular limits: a semi-classical limit in the transport direction and the strong partial confinement limit in the transversal direction. We prove that both limits commute together and we provide convergence rates. The by-products of this work are approximated models in reduced dimension for the GPE, with a priori estimates of the approximation errors. This is a joint work with Weizhu Bao and Loic Le Treust.
Tuesday October 14, 2014
Logic Seminar
TBA
Erik Walsberg (UCLA)
4:00 PM in SEO 427
Wednesday October 15, 2014
Distinguished Lecture Series
The "P vs. NP" problem: efficient computation, Internet security, and the limits to human knowledge
Avi Wigderson (Institute for Advanced Study)
4:00 PM in TBA
The "P vs. NP" problem, formulated by computer theorists in the 1970s, quickly became a central outstanding problem of science and mathematics. In this talk I will attempt to describe its mathematical, scientific and philosophical content. I will discuss its status, and the implications of its resolution on science and technology (making clear that the \$1M prize on solving it pales in comparison with these implications). No special background will be assumed. Statistics Seminar TBA Mengyu Xu (University of Chicago) 4:00 PM in SEO 636 Thursday October 16, 2014 Distinguished Lecture Series Randomness Avi Wigderson (Institute for Advanced Study) 3:00 PM in SEO 636 Is the universe inherently deterministic or probabilistic? Perhaps more importantly - can we tell the difference between the two? Humanity has pondered the meaning and utility of randomness for millennia. There is a remarkable variety of ways in which we utilize perfect coin tosses to our advantage: in statistics, cryptography, game theory, algorithms, gambling... Indeed, randomness seems indispensable! Which of these applications survive if the universe had no randomness in it at all? Which of them survive if only poor quality randomness is available, e.g. that arises from "unpredictable" phenomena like the weather or the stock market? A computational theory of randomness, developed in the past three decades, reveals (perhaps counter-intuitively) that very little is lost in such deterministic or weakly random worlds. In the talk I'll explain the main ideas and results of this theory. The talk is aimed at a general scientific audience. Logic Seminar Intersections of isogeny classes and varieties James Freitag (UC Berkeley) 4:00 PM in SEO 427 Take$ \alpha \in GL_2$and a complex number$a$. There are at most$36^7$complex numbers$b$such that the elliptic curves$E_a$and$E_b$are isogenous and$E_ {\alpha (a)}$and$E_ {\alpha (b)} $are isogenous. Proving this fact along with an effective form of a special case of the Zilber-Pink conjecture uses input from model theory, differential algebra, and diophantine geometry. We will describe the proof and partial generalizations to various moduli spaces of abelian varieties. Friday October 17, 2014 Distinguished Lecture Series Permanent & Determinant: non-identical twins Avi Wigderson (Institute for Advanced Study) 3:00 PM in SEO 636 The determinant is undoubtedly the most important polynomial function in mathematics. Its lesser known sibling, the permanent, plays very important roles in enumerative combinatorics, statistical and quantum physics, and the theory of computation. In this lecture I plan to survey some of the remarkable properties of the permanent, its applications and impact on fundamental computational problems, its similarities to and apparent differences from the determinant, and how these relate to the P vs. NP prolem. This lecture is intended to a general Math & CS audience. Monday October 20, 2014 Combinatorics Seminar TBA Choongbum Lee (MIT) 3:00 PM in SEO 427 Geometry, Topology and Dynamics Seminar TBA Kiran Parkhe (Technion University, Israel) 3:00 PM in SEO 636 Applied Mathematics Seminar TBA Kasso Okoudjou (University of Maryland) 4:00 PM in SEO 636 Tuesday October 21, 2014 Algebraic Geometry Seminar Cartan-Fubini type extension of holomorphic maps preserving webs of rational curves Jun-Muk Hwang (Korea Institute for Advanced Study (KIAS)) 4:00 PM in TBA Let$X_1$and$X_2$with$\mathrm{dim} X_1 = \mathrm{dim} X_2$be two projective manifolds of Picard number 1 in projective space. Assume that both$X_1$and$X_2$are covered by lines. Let$\varphi: U_1 \to U_2$be a biholomorphic map between two connected Euclidean open subsets$U_1 \subset X_1$and$U_2 \subset X_2$. Suppose that both$\varphi$and$\varphi^{-1}$send pieces of lines to pieces of lines. We show that$\varphi$can be extended to a biregular morphism$\Phi: X_1 \to X_2$. This was proved by Hwang-Mok in 2001 when the indices of$X_1$and$X_2\$ are bigger than 2 and the new result is when the indices are 2. In this case, the covering family of lines form webs of rational curves. We exploit the monodromy of the webs of lines to extend the holomorphic map.
Wednesday October 22, 2014
Statistics Seminar
TBA
Wei Zheng (IUPUI)
4:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Alex Kuronya (Budapest University of Technology and Economics)
4:00 PM in SEO 427
Friday October 24, 2014
Algebraic Topology Seminar
Duality and Tilting for Commutative DG Rings
Amnon Yekutieli (Ben Gurion University)
2:00 PM in SEO 1227
We study super-commutative nonpositive DG rings. An example is the Koszul complex associated to a sequence of elements in a commutative ring. More generally such DG rings arise as semi-free resolutions of rings. They are also the affine DG schemes in derived algebraic geometry. The theme of this talk is that in many ways a DG ring A resembles an infinitesimal extension, in the category of rings, of the ring H^0(A).
I first discuss localization of DG rings on Spec(H^0(A)) and the cohomological noetherian property. Then I introduce perfect, tilting and dualizing DG A-modules. Existence of dualizing DG modules is proved under quite general assumptions. The derived Picard group DPic(A) of A, whose objects are the tilting DG modules, classifies dualizing DG modules. It turns out that DPic(A) is canonically isomorphic to DPic(H^0(A)), and that latter group is known by earlier work. A consequence is that A and H^0(A) have the same (isomorphism classes of) dualizing DG modules.

Departmental Colloquium
TBA
Jianguo Sun (University of Missouri)
3:00 PM in SEO 636
Monday October 27, 2014
Geometry, Topology and Dynamics Seminar
TBA
Sonja Stimac (University of Zagreb and IUPUI)
3:00 PM in SEO 636

Geometry, Topology and Dynamics Seminar
TBA
Sheel Ganatra (Stanford University)
3:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Chenyang Xu (Beijing International Center of Mathematics Research)
4:00 PM in SEO 427

Applied Mathematics Seminar
TBA
Rafael Iorio (Instituto Nacional de Matemática Pura e Aplicada)
4:00 PM in SEO 636
Tuesday October 28, 2014
Logic Seminar
Midwest Model Theory Day
C. Ward Henson, Krzysztof Krupiński and Ramin Takloo-Bighash
1:00 PM in SEO 636
There will be no logic seminar. Instead, we will be hosting Midwest Model Theory Day http://math.wisc.edu/~andrews/MWMTD8.html.
Wednesday October 29, 2014
Algebraic Geometry Seminar
TBA
Brooke Ullery (University of Michigan)
4:00 PM in SEO 427

Statistics Seminar
Some important statistical considerations in biomarker discovery from high-dimensional data
V. Devanarayan (AbbVie)
4:00 PM in SEO 636
Biomarkers such as those based on genomic, proteomic and imaging modalities play a vital role in biopharmaceutical R&D. Examples include the discovery of novel genes/targets related to various diseases based on which a suitable therapeutic can be developed, diagnostics for different disease subtypes, identification of patients that are more likely to progress in disease or benefit from a particular therapeutic, etc. The discovery of such biomarkers are typically based on the evaluation of high-dimensional datasets that require a strong combination of bioinformatic and statistical considerations. This seminar will provide a practical overview and intuitive explanation of some important concepts and considerations around the analyses of such high-dimensional data.
Friday October 31, 2014
Departmental Colloquium
The Role of Entanglement in DNA Structure and Function
De Witt Sumners (Florida State University)
3:00 PM in SEO 636
This talk will survey some of the results on properties of random knots in 3-space and in confined volumes, with applications to enzyme action on duplex DNA and the structure and dynamics of duplex DNA confined to viral capsids. This talk is intended for a general mathematical audience.
Monday November 3, 2014
Applied Mathematics Seminar
4-stochastic measures minimizations and polyconvexity
Romeo Awi (Georga Tech)
4:00 PM in SEO 636
Wednesday November 5, 2014
Algebraic Geometry Seminar
TBA
Daniel Litt (Stanford University)
4:00 PM in SEO 427

Statistics Seminar
TBA
Sonja Petrovic (IIT)
4:00 PM in SEO 636
Friday November 7, 2014
Departmental Colloquium
TBA
Wilfrid Gangbo (Georgia Tech)
3:00 PM in SEO 636
Monday November 10, 2014
Geometry, Topology and Dynamics Seminar
TBA
Ronen Mukamel (University of Chicago)
3:00 PM in SEO 636

TBA
Natasa Pavlovic (UT Austin)
3:00 PM in TBA

Applied Mathematics Seminar
TBA
Natasa Pavlovic (University of Texas at Austin)
4:00 PM in SEO 636
Wednesday November 12, 2014
Statistics Seminar
Optimal Plate Designs in High Throughput Screening Experiments
Xianggui Qu (Oakland University)
4:00 PM in SEO 636
High-throughput screening (HTS) is a large-scale process that screens hundreds of thousands to millions of compounds in order to identify potentially leading candidates rapidly and accurately. There are many statistically challenging issues in HTS. In this talk, I will focus the spatial effect in primary HTS. I will discuss the consequences of spatial effects in selecting leading compounds and why the current experimental design fails to eliminate these spatial effects. A new class of designs will be proposed for elimination of spatial effects. The new designs have the advantages such as all compounds are comparable within each microplate in spite of the existence of spatial effects; the maximum number of compounds in each microplate is attained, etc. Optimal designs are recommended for HTS experiments with multiple controls.

Algebraic Geometry Seminar
TBA
Howard Nuer (Rutgers University)
4:00 PM in SEO 427
Friday November 14, 2014
Departmental Colloquium
TBA
Jun Liu (Harvard)
3:00 PM in SEO 636
Monday November 17, 2014
Geometry, Topology and Dynamics Seminar
TBA
Ailsa Keating (Columbia University)
3:00 PM in SEO 636

Applied Mathematics Seminar
A High-Order Perturbation of Surfaces (HOPS) Method for Simulating Surface Plasmons on Periodic Gratings
David Nicholls (UIC)
4:00 PM in SEO 636
Tuesday November 18, 2014
Logic Seminar
TBA
John Baldwin (UIC)
4:00 PM in SEO 427
Wednesday November 19, 2014
Statistics Seminar
TBA / TBA
Raymond Mess / Nick Syring (UIC)
4:00 PM in SEO 636

Algebraic Geometry Seminar
TBA
Eric Riedl (Harvard University)
4:00 PM in SEO 427
Monday November 24, 2014
Applied Mathematics Seminar
TBA
Wujun Zhang (University of Maryland)
4:00 PM in SEO 636
Wednesday November 26, 2014
Algebraic Geometry Seminar
N/A
NO SEMINAR (Thanksgiving)
4:00 PM in SEO 427
Wednesday December 3, 2014
Algebraic Geometry Seminar
TBA
Ana-Maria Castravet (Ohio State University)
4:00 PM in SEO 427

Algebraic Geometry Seminar
TBA
Emanuele Macri (Ohio State University)
5:00 PM in SEO 427
Wednesday April 1, 2015
Algebraic Geometry Seminar
TBA
Claire Voisin (CNRS and IAS)
4:00 PM in SEO 427
Friday May 1, 2015
Departmental Colloquium
Atkin Memorial Lecture
Alireza Salehi-Golsefidi (University of California, San Diego )
3:00 PM in TBA
UIC LAS MSCS seminars seminar calendar