Talk_id  Date  Speaker  Title 
17497

Monday 1/7 4:10 PM

Matthew Ballard, University of South Carolina

Exceptional collections: what they are and where to find them (special colloquium)
 Matthew Ballard, University of South Carolina
 Exceptional collections: what they are and where to find them (special colloquium)
 01/07/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Analogous to orthonormal bases in linear algebra, exceptional collections in triangulated categories are the most atomic means of decomposition. In this talk, we will introduce exceptional collections drawing heavily on examples from noncommutative algebra, algebraic geometry and symplectic geometry. We will then address the question of where (and how) to find them.

17495

Wednesday 1/9 4:10 PM

Eugenia Malinnikova, Norwegian University of Science and Technology

Quantitative unique continuation for elliptic PDEs and application (special colloquium)
 Eugenia Malinnikova, Norwegian University of Science and Technology
 Quantitative unique continuation for elliptic PDEs and application (special colloquium)
 01/09/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
If a solution to a uniformly elliptic second order PDE with smooth coefficients vanishes on an open subset of a domain then it is zero on the whole domain. This is a classical result known as weak unique continuation. We will discuss stronger versions, including some recent quantitative results and outline applications to the study of eigenfunctions of LaplaceBeltrami operator on compact manifolds.

17501

Friday 1/11 4:10 PM

Pavlo Pylyavskyy, University of Minnesota

Zamolodchikov periodicity and integrability (special colloquium)
 Pavlo Pylyavskyy, University of Minnesota
 Zamolodchikov periodicity and integrability (special colloquium)
 01/11/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Tsystems are certain discrete dynamical systems associated with quivers. They appear in several different contexts: quantum affine algebras and Yangians, commuting transfer matrices of vertex models, character theory of quantum groups, analytic Bethe ansatz, WronskianCasoratian duality in ODE, gauge/string theories, etc. Periodicity of certain Tsystems was the main conjecture in the area until it was proven by Keller in 2013 using cluster categories. In this work we completely classify periodic Tsystems, which turn out to consist of 5 infinite families and 4 exceptional cases, only one of the infinite families being known previously. We then proceed to classify Tsystems that exhibit two forms of integrability: linearization and zero algebraic entropy. All three classifications rely on reduction of the problem to study of commuting Cartan matrices, either of finite or affine types. The finite type classification was obtained by Stembridge in his study of KazhdanLusztig theory for dihedral groups, the other two classifications are new. This is joint work with Pavel Galashin.

17500

Monday 1/14 4:10 PM

Alex Blumenthal, University of Maryland

Chaotic regimes for random dynamical systems (special colloquium)
 Alex Blumenthal, University of Maryland
 Chaotic regimes for random dynamical systems (special colloquium)
 01/14/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
It is anticipated that chaotic regimes (characterized by, e.g., sensitivity with respect to initial conditions and loss of memory) arise in a wide variety of dynamical systems, including those arising from the study of ensembles of gas particles and fluid mechanics. However, in most cases the problem of rigorously verifying asymptotic chaotic regimes is notoriously difficult. For volumepreserving systems (e.g., incompressible fluid flow or Hamiltonian systems), these issues are exemplified by coexistence phenomena: even in quite simple models which should be chaotic, e.g. the Chirikov standard map, completely opposite dynamical regimes (elliptic islands vs. hyperbolic sets) can be tangled together in phase space in a convoluted way.
Recent developments have indicated, however, that verifying chaos is tractable for systems subjected to a small amount of noise— from the perspective of modeling, this is not so unnatural, as the real world is inherently noisy. In this talk, I will discuss two recent results: (1) a large positive Lyapunov exponent for (extremely small) random perturbations of the Chirikov standard map, and (2) a positive Lyapunov exponent for the Lagrangian flow corresponding to various incompressible stochastic fluids models, including stochastic 2D NavierStokes and 3D hyperviscous NavierStokes on the periodic box. The work in this talk is joint with Jacob Bedrossian, Samuel PunshonSmith, Jinxin Xue and LaiSang Young.

17502

Wednesday 1/16 1:40 PM

Goncalo Oliveira, Universidade Federal Fluminense, Rio de Janeiro

Gauge theory on AloffWallach spaces
 Goncalo Oliveira, Universidade Federal Fluminense, Rio de Janeiro
 Gauge theory on AloffWallach spaces
 01/16/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
I will describe joint work with Gavin Ball constructing and classifying G2instantons on AloffWallach spaces, which are the most interesting known examples of compact "nearlyparallel" G2manifolds.

15383

Thursday 1/17 2:00 PM

Chris Kottke, New College Florida

Compactification of monopole moduli spaces
 Chris Kottke, New College Florida
 Compactification of monopole moduli spaces
 01/17/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
I will discuss joint work with Michael Singer and Karsten Fritzsch on compactifications of the moduli spaces $M_k$ of $\mathrm{SU}(2)$ magnetic monopoles on $\mathbf{R}^3$ . Via a geometric gluing procedure, we construct manifolds with corners compactifying the $M_k$ , the boundaries of which represent monopoles of charge $k$ decomposing into widely separated ‘monopole clusters' of lower charge. The hyperkahler metric on $M_k$ has a complete asymptotic expansion, the leading terms of which generalize the asymptotic metric discovered by Bielawski, Gibbons and Manton in the case that the monopoles are all widely separated. From the structure of the compactification, we are able to make partial progress toward proving Sen's conjecture for $L^2$ cohomology of the moduli spaces.

17506

Thursday 1/17 3:00 PM

Daping Weng, MSU

More on Scattering Diagram and Theta Functions
 Daping Weng, MSU
 More on Scattering Diagram and Theta Functions
 01/17/2019
 3:00 PM  4:00 PM
 C117 Wells Hall
I will continue the discussion on scattering diagram and theta functions and relate them to the classical cluster theories. I will sketch GrossHackingKeelKontsevich’s proofs of positive Laurent phenomenon, sign coherence, and a weak version of the cluster duality conjecture.

17503

Monday 1/21 1:40 PM

Zhe Zhang, MSU

Harmonic map flow in dimension two, I
 Zhe Zhang, MSU
 Harmonic map flow in dimension two, I
 01/21/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
Bubbling analysis due to Struwe.

17496

Monday 1/21 4:10 PM

Wencai Liu, University of California, Irvine

Universal arithmetical hierarchy of eigenfunctions for supercritical almost Mathieu operators (special colloquium)
 Wencai Liu, University of California, Irvine
 Universal arithmetical hierarchy of eigenfunctions for supercritical almost Mathieu operators (special colloquium)
 01/21/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
The Harper's model is a tightbinding description of Bloch electrons on $\mathbb{Z}^2$ under a constant transverse magnetic field.
In 1964, Mark Azbel predicted that both spectra and eigenfunctions of this model
have selfsimilar hierarchical structure driven by the continued fraction expansion of the irrational magnetic flux.
In 1976, the hierarchical structure of spectra was discovered numerically by Douglas Hofstadter, and was later observed in various experiments. The mathematical study of Harper's model led to the development of spectral theory of the almost Mathieu operator, with the solution of the Ten Martini Problem partially confirming the fractal structure of the spectrum.
In this talk we will present necessary background and discuss the main ideas behind our confirmation (joint with S. Jitomirskaya) of Azbel's second prediction of the structure of the eigenfunctions. More precisely, we show that the eigenfunctions of the almost Mathieu operators in the localization regime, feature selfsimilarity governed by the continued fraction expansion of the frequency. These results also lead to the proof of sharp arithmetic transitions between pure point and singular continuous spectra, both in the frequency and the phase, as conjectured in 1994.

17511

Wednesday 1/23 10:20 AM

Stavros Garoufalidis, Georgia Institute of Technology

A brief history of quantum topology (special colloquium)
 Stavros Garoufalidis, Georgia Institute of Technology
 A brief history of quantum topology (special colloquium)
 01/23/2019
 10:20 AM  11:10 AM
 C304 Wells Hall
Quantum topology originated from Vaughan Jones's discovery of the Jones polynomial of a knot in 1985. I will explain the area and its interaction with mathematical physics, algebra, analysis, number theory and combinatorics.

16468

Thursday 1/24 2:00 PM

Rebecca Winarski, University of Michigan

Solving the Twisted Rabbit Problem using trees
 Rebecca Winarski, University of Michigan
 Solving the Twisted Rabbit Problem using trees
 01/24/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
The twisted rabbit problem is a celebrated problem in complex dynamics. Work of Thurston proves that up to equivalence, there are exactly three branched coverings of the sphere to itself satisfying certain conditions. When one of these branched coverings is modified by a mapping class, a map equivalent to one of the three coverings results. Which one?
After remaining open for 25 years, this problem was solved by BartholdiNekyrashevych using iterated monodromy groups. In joint work with Belk, Lanier, and Margalit, we present an alternate solution using topology and geometric group theory that allows us to solve a more general problem.

17512

Thursday 1/24 3:00 PM

Daping Weng, MSU

More on Scattering Diagram and Theta Functions
 Daping Weng, MSU
 More on Scattering Diagram and Theta Functions
 01/24/2019
 3:00 PM  4:00 PM
 C204A Wells Hall
I will continue the discussion on scattering diagram and theta functions and relate them to the classical cluster theories. I will sketch GrossHackingKeelKontsevich’s proofs of positive Laurent phenomenon, sign coherence, and a weak version of the cluster duality conjecture.

17504

Monday 1/28 1:40 PM

Zhe Zhang, MSU

Harmonic map flow in dimension two, II
 Zhe Zhang, MSU
 Harmonic map flow in dimension two, II
 01/28/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
Bubble tree analysis and energy identity.

17526

Monday 1/28 3:00 PM

Nick Ovenhouse, MSU

Total Positivity
 Nick Ovenhouse, MSU
 Total Positivity
 01/28/2019
 3:00 PM  4:00 PM
 C517 Wells Hall
A matrix is "totally positive" if all of its minors are positive. We will discuss combinatorial models of total positivity using weighted graphs, as well as some criteria and characterizations for checking total positivity. If there is time, we will also discuss total positivity in the Grassmannian manifold, along with combinatorial models.

17529

Wednesday 2/6 1:40 PM

Tom Parker, MSU

Convergence modulo diffeomorphisms of maps from Riemann surfaces
 Tom Parker, MSU
 Convergence modulo diffeomorphisms of maps from Riemann surfaces
 02/06/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
For the theory of both harmonic and holomorphic maps, one needs a notion of convergence maps modulo diffeomorphisms of the domain. I will describe an approach (developed with Woongbae Park) that uses Kuranishi families in place of the standard approach based on bubble tree convergence.

17515

Wednesday 2/6 4:10 PM

Abhishek Mallick

Computations in equivariant Floer homology
 Abhishek Mallick
 Computations in equivariant Floer homology
 02/06/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Following HendricksLipshitz Sarkar we discuss the construction of equivariant Floer homology and a few cases where it can be computed.

16478

Wednesday 2/6 4:10 PM

Mihai Tohaneanu, University of Kentucky

Local energy estimates on black hole backgrounds
 Mihai Tohaneanu, University of Kentucky
 Local energy estimates on black hole backgrounds
 02/06/2019
 4:10 PM  5:00 PM
 C517 Wells Hall
Local energy estimates are a robust way to measure decay of solutions to linear wave equations. I will discuss several such results on black hole backgrounds, such as Schwarzschild, Kerr, and suitable perturbations converging at various rates, and briefly discuss applications to nonlinear problems. The most challenging geometric feature one needs to deal with is the presence of trapped null geodesics, whose presence yield unavoidable losses in the estimates. This is joint work with Lindblad, Marzuola, Metcalfe, and Tataru.

15394

Thursday 2/7 2:00 PM

Adam Sikora, SUNY at Buffalo

New Approach to Quantum Teichmuller Theory
 Adam Sikora, SUNY at Buffalo
 New Approach to Quantum Teichmuller Theory
 02/07/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
The Jones polynomial invariant of links in R^3 extends to links in thickened surfaces, leading to the notion of the skein algebra of a surface, which is a version of ChekhovFock quantum Teichmuller space. The algebraic structure of skein algebras is quite rich and mysterious. We will approach it using the theory of measured foliations and pseudoAnosov diffeomorphisms of surfaces

17527

Thursday 2/7 3:00 PM

Elizabeth Munch, MSU

The Interleaving Distance for a Category with a Flow
 Elizabeth Munch, MSU
 The Interleaving Distance for a Category with a Flow
 02/07/2019
 3:00 PM  3:50 PM
 C304 Wells Hall
All data has noise, and rigorously understanding how your analysis fares in the face of that noise requires a notion of a metric. The idea of the interleaving distance arose in the context of generalizing metrics for persistence modules from the field of topological data analysis (TDA). Essentially, the idea is that two objects in a category should be distance 0 if there is an isomorphism between them; the distance between two objects should be "almost" 0 if there is "almost" an isomorphism between them. Placed in the right context, we can measure what we mean by an "almost'' isomorphism and use this to define a distance.
Building on the work of Chazal et al.; and Bubenick, Scott, and de Silva, we will discuss the generalization of the notion of the interleaving distance to a socalled "category with a flow". We will show that this generalization provides metrics for many different categories of interest in TDA and beyond, including Reeb graphs, merge trees, phylogenetic trees, and mapper graphs. This work is the result of collaborations with Anastasios Stefanou, Vin de Silva, and Amit Patel.

17528

Thursday 2/7 3:00 PM

Alek Vainshtein, University of Haifa

Exotic cluster structures on SL_n
 Alek Vainshtein, University of Haifa
 Exotic cluster structures on SL_n
 02/07/2019
 3:00 PM  4:00 PM
 C204A Wells Hall
Back in 2005, Berenstein, Fomin and Zelevinsky discovered a cluster
structure in the ring of regular functions on a double Bruhat cell in a
semisimple Lie group, in particular, SL_n. This structure can be easily
extended to the whole group. The compatible Poisson bracket is given by
the standard rmatrix PoissonLie structure on SL_n. The latter is a
particular case of PoissonLie structures corresponding to
quasitriangular Lie bialgebras. Such structures where classified in
1982 by Belavin and Drinfeld. In 2012, we have conjectured that each
PoissonLie structure on SL_n gives rise to a cluster structure, and
gave several examples of exotic cluster structures corresponding to
PoissonLie structures distinct from the standard one. In my talk I will
tell about the progress in the proof of this conjecture and its
modifications.
Joint with M.Gekhtman and M.Shapiro.

17530

Monday 2/11 1:40 PM

Xiaodong Wang, MSU

Harmonic maps and superrigidity (after MokSiuYeung)
 Xiaodong Wang, MSU
 Harmonic maps and superrigidity (after MokSiuYeung)
 02/11/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
No abstract available.

17513

Monday 2/11 4:10 PM

Cori FataHartley and Cheryl Sisk

Designation B Process
 Cori FataHartley and Cheryl Sisk
 Designation B Process
 02/11/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Dr. FataHartley and Dr. Sisk will describe the Designation B requirements and application process. They will answer questions about eligibility, timeline, procedures, etc.

17490

Wednesday 2/13 4:10 PM

Albert Ai, UC Berkeley

Low Regularity Solutions for Gravity Water Waves
 Albert Ai, UC Berkeley
 Low Regularity Solutions for Gravity Water Waves
 02/13/2019
 4:10 PM  5:00 PM
 C517 Wells Hall
We consider the local wellposedness of the Cauchy problem for the gravity water waves equations, which model the free interface between a fluid and air in the presence of gravity. It has been known that by using dispersive effects, one can lower the regularity threshold for wellposedness, below that which is attainable by energy estimates alone. This program was initiated for gravity water waves by AlazardBurqZuily, by proving Strichartz estimates with loss. We discuss how these Strichartz estimates, and thus the low regularity threshold, can be sharpened by applying an integration along the Hamilton flow combined with local smoothing estimates.

17516

Wednesday 2/13 4:10 PM

Keshav Sutrave

Harmonic map heat flow
 Keshav Sutrave
 Harmonic map heat flow
 02/13/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
The harmonic map flow equation and EellsSampson theorem.

17499

Thursday 2/14 2:00 PM

Melissa Zhang, Boston College

Localization in Khovanov homology
 Melissa Zhang, Boston College
 Localization in Khovanov homology
 02/14/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
When a topological object admits a group action, we expect that our invariants reflect this symmetry in their structure. This talk will tour the expression of link symmetries in three generations of related invariants: the Jones polynomial; its categorification, Khovanov homology; and the youngest invariant in the family, the Khovanov stable homotopy type, introduced by Lipshitz and Sarkar. I will describe how to use LawsonLipshitzSarkar's Burnside functor construction of the LipshitzSarkar Khovanov homotopy type to produce localization theorems and Smithtype inequalities for the Khovanov homology of periodic links. This joint work with Matthew Stoffregen.

17507

Thursday 2/14 3:00 PM

Alexander Shapiro, The University of Edinburgh

Positive PeterWeyl theorem
 Alexander Shapiro, The University of Edinburgh
 Positive PeterWeyl theorem
 02/14/2019
 3:00 PM  4:00 PM
 C204A Wells Hall
The classical PeterWeyl theorem asserts that the regular representation of a compact Lie group $G$ on the space of squareintegrable functions $L^2(G)$ decomposes as the direct sum of all irreducible unitary representations of $G$. In the talk, I will use positive representations of cluster varieties, to obtain a "noncompact" quantum analogue of the PeterWeyl theorem. This is joint work with Ivan Ip and Gus Schrader.

17532

Friday 2/15 4:10 PM

Nicolas Garcia Trillos, University of WisconsinMadison

Large sample asymptotics of spectra of Laplacians and semilinear elliptic PDEs on random geometric graphs
 Nicolas Garcia Trillos, University of WisconsinMadison
 Large sample asymptotics of spectra of Laplacians and semilinear elliptic PDEs on random geometric graphs
 02/15/2019
 4:10 PM  5:00 PM
 1502 Engineering Building
Given a data set $\mathcal{X}=\{x_1, \dots, x_n\}$ and a weighted graph structure $\Gamma= (\mathcal{X},W)$ on $\mathcal{X}$, graph based methods for learning use analytical notions like graph Laplacians, graph cuts, and Sobolev seminorms to formulate optimization problems whose solutions serve as sensible approaches to machine learning tasks. When the data set consists of samples from a distribution supported on a manifold (or at least approximately so), and the weights depend inversely on the distance between the points, a natural question to study concerns the behavior of those optimization problems as the number of samples goes to infinity. In this talk I will focus on optimization problems closely connected to clustering and supervised regression that involve the graph Laplacian. For clustering, the spectrum of the graph Laplacian is the fundamental object used in the popular spectral clustering algorithm. For regression, the solution to a semilinear elliptic PDE on the graph provides the minimizer of an energy balancing regularization and data fidelity, a sensible object to use in nonparametric regression.
Using tools from optimal transport, calculus of variations, and analysis of PDEs, I will discuss a series of results establishing the asymptotic consistency (with rates of convergence) of many of these analytical objects, as well as provide some perspectives on future research directions.

17533

Friday 2/15 4:10 PM

Willie Wong, MSU

In the beginning ... : Big Bang and Bianchi IX
 Willie Wong, MSU
 In the beginning ... : Big Bang and Bianchi IX
 02/15/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Big Bang Theory is now an established part of cosmology. A common mental picture of the big bang singularity is that of the Friedman model, where, looking backwards in time, the universe collapses uniformly to one point leaving the shape unchanged. In 1970, however, the Russian physicists Belinskii, Khalatnikov, and Lifshitz showed that the Friedmaninspired picture is far from common. In fact they proposed an alternative picture where near the beginning of time, the generic universe rapidly and chaotically oscillates between different "shapes" as it shrinks down to a single point. I aim to explain some of the things we now know about this BKL conjecture, including an interesting connection to the continued fraction expansion of real numbers and the golden ratio.

17531

Monday 2/18 1:40 PM

Leonardo Abbrescia, MSU

Moser iteration for parabolic equations
 Leonardo Abbrescia, MSU
 Moser iteration for parabolic equations
 02/18/2019
 1:40 PM  3:00 PM
 C517 Wells Hall
No abstract available.

17540

Monday 2/18 3:00 PM

Charlotte Ure, MSU

Prime Torsion of the Brauer Group of an Elliptic Curve
 Charlotte Ure, MSU
 Prime Torsion of the Brauer Group of an Elliptic Curve
 02/18/2019
 3:00 PM  4:00 PM
 C517 Wells Hall
The Brauer group is an invariant, that can detect arithmetic properties of the underlying variety. In this talk, I will define the Brauer group of a variety, describe it's connection to rational points, and give an algorithm to calculate generators and relations of the qtorsion of the Brauer group of and elliptic curve., where q is prime. This talk will be accessible to all.

17514

Tuesday 2/19 2:00 PM

Paul Dawkins, Northern Illinois University

The use(s) of “is” in Mathematics
 Paul Dawkins, Northern Illinois University
 The use(s) of “is” in Mathematics
 02/19/2019
 2:00 PM  3:30 PM
 252 EH
This talk presents analysis of some of the ambiguities that arise among statements with the copular verb “is" in the mathematical language of textbooks as compared to daytoday English language. We identify patterns in the construction and meaning of is statements using randomly selected examples from corpora representing the two linguistic registers. We categorize these examples according to the part of speech of the object word in the grammatical form “[subject] is [object].” In each such grammatical category, we compare the relative frequencies of the subcategories of logical relations conveyed by that construction. Within some categories we observe that the same grammatical structure alternatively conveys different logical relations and that the intended logical relation can only sometimes be inferred from the grammatical cues in the statement itself. This means that one can only interpret the intended logical relation by already knowing the relation among the semantic categories in question. Such ambiguity clearly poses a communicative challenge for teachers and students. We discuss the pedagogical significance of these patterns in mathematical language and consider the relationship between these patterns and mathematical practices.

17517

Wednesday 2/20 4:10 PM

Zhe Zhang

A construction of the DeligneMumford orbifold
 Zhe Zhang
 A construction of the DeligneMumford orbifold
 02/20/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
Isomorphism classes $M_{g,n}$ of stable nodal Riemann surfaces of arithmetic genus g with n marked points. A marked nodal Riemann surface is stable if and only if its isomorphism group is finite. A natural construction based on the existence of universal unfoldings endows the DeligneMumford moduli space with an orbifold structure. Here we use the methods of differential geometry rather than algebraic geometry.

17505

Thursday 2/21 2:00 PM

Ilya Gekhtman , University of Toronto

Growth rates of invariant random subgroups of hyperbolic groups and rank 1 Lie groups.
 Ilya Gekhtman , University of Toronto
 Growth rates of invariant random subgroups of hyperbolic groups and rank 1 Lie groups.
 02/21/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
Abstract: Invariant random subgroups (IRS) are conjugacy invariant probability measures on the space of subgroups of a given group G. They arise naturally as point stabilizers of probability measure preserving actions. The space of invariant random subgroups of SL_{2}R can be regarded as a natural compactification of the moduli space of Riemann surfaces, related to the DeligneMumford compactification. Invariant random subgroups can be regarded as a generalization both of normal subgroups and of lattices in topological groups. As such, it is interesting to extend results from the theories of normal subgroups and of lattices to the IRS setting.
Jointly with Arie Levit, we prove such a result: the critical exponent (exponential growth rate) of an infinite IRS in an isometry group of a Gromov hyperbolic space (such as a rank 1 Lie group, or a hyperbolic group) is almost surely greater than half the Hausdorff dimension of the boundary.
This generalizes an analogous result of MatsuzakiYabukiJaerisch for normal s
As a corollary, we obtain that if $\Gamma$ is a typical subgroup and $X$ a rank 1 symmetric space then $\lambda_{0}(X/\Gamma)<\lambda_{0}(X)$ where $\lambda_0$ is the bottom of the spectrum of the Laplacian. The proof uses ergodic theorems for actions of hyperbolic groups.
I will also talk about results about growth rates of normal subgroups of hyperbolic groups that inspired this work.

17539

Thursday 2/21 3:00 PM

Xiaochuan Yang, University of Luxembourg

BerryEsseen Bounds in the BreuerMajor Central Limit Theorem
 Xiaochuan Yang, University of Luxembourg
 BerryEsseen Bounds in the BreuerMajor Central Limit Theorem
 02/21/2019
 3:00 PM  3:50 PM
 C405 Wells Hall
The BreuerMajor theorem provides sufficient conditions in order that a normalized sum of nonlinear functionals of Gaussian random fields exhibits Gaussian fluctuation. Such a result has farreaching applications in statistical inference of Gaussian models. In this talk, I will be focusing on the rate of convergence in the total variation distance of the BreuerMajor theorem. To this end, we apply Malliavin calculus (stochastic calculus of variation) techniques, Stein’s method for normal approximations, and Gebelein’s inequality for functionals of correlated Gaussian fields. Based on joint work with I. Nourdin and G. Peccati.

17535

Monday 2/25 4:10 PM

Round Table Discussion

Pros and Cons for Evening Exams for Uniform Courses
 Round Table Discussion
 Pros and Cons for Evening Exams for Uniform Courses
 02/25/2019
 4:10 PM  5:00 PM
 C109 Wells Hall
No abstract available.

17518

Wednesday 2/27 4:10 PM

Woongbae Park

TBA
 Woongbae Park
 TBA
 02/27/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17509

Thursday 2/28 2:00 PM

Eva Belmont, Northwestern University

TBA
 Eva Belmont, Northwestern University
 TBA
 02/28/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
No abstract available.

17543

Thursday 2/28 3:00 PM

Linhui Shen, MSU

Cluster structure on moduli spaces of local systems for general groups
 Linhui Shen, MSU
 Cluster structure on moduli spaces of local systems for general groups
 02/28/2019
 3:00 PM  4:00 PM
 C204A Wells Hall
There have been several references in the literature devoted to the study of the cluster structures on moduli spaces of Glocal systems, all of which are based on case by case study. In this talk, we present a systematic construction that works for all groups at once. As an application, we will investigate the principal series representations of quantum groups from the perspective of cluster theory.

17537

Thursday 3/7 2:00 PM

SPRING BREAK

SPRING BREAK
 SPRING BREAK
 SPRING BREAK
 03/07/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
No abstract available.

17536

Monday 3/11 4:10 PM

Round Table Discussion

Poll Everywhere and other inclass participation technologies
 Round Table Discussion
 Poll Everywhere and other inclass participation technologies
 03/11/2019
 4:10 PM  5:00 PM
 C109 Wells Hall
No abstract available.

17520

Wednesday 3/13 4:10 PM

Hitesh Gakhar

TBA
 Hitesh Gakhar
 TBA
 03/13/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17491

Wednesday 3/13 4:10 PM

Jonas Lührmann, Johns Hopkins

Local smoothing estimates for Schrödinger equations on hyperbolic space and applications
 Jonas Lührmann, Johns Hopkins
 Local smoothing estimates for Schrödinger equations on hyperbolic space and applications
 03/13/2019
 4:10 PM  5:00 PM
 C517 Wells Hall
We establish frequencylocalized local smoothing estimates for Schrödinger equations on hyperbolic space. The proof is based on the positive commutator method and a heat flow based LittlewoodPaley theory. Our results and techniques are motivated by applications to the problem of stability of solitary waves to nonlinear Schrödingertype equations on hyperbolic space.
The talk is based on joint work with Andrew Lawrie, SungJin Oh, and Sohrab Shahshahani.

15423

Thursday 3/14 2:00 PM

Luca Spolaor, Massachusetts Institute of Technology

TBA
 Luca Spolaor, Massachusetts Institute of Technology
 TBA
 03/14/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
No abstract available.

17542

Thursday 3/14 5:30 PM

AMS Student Chapter, MSU

Math trivia night
 AMS Student Chapter, MSU
 Math trivia night
 03/14/2019
 5:30 PM  7:30 PM
 C204 Wells Hall
The AMS Student Chapter is hosting a math trivia night on pi day! Please join us for a potluck and a lot of fun.

17534

Friday 3/15 4:10 PM

Peter Magyar, MSU

TBA
 Peter Magyar, MSU
 TBA
 03/15/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17521

Wednesday 3/20 4:10 PM

Sanjay Kumar

TBA
 Sanjay Kumar
 TBA
 03/20/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

14368

Thursday 3/21 4:10 PM

Wilfrid Gangbo, University of California, Los Angeles

TBA
 Wilfrid Gangbo, University of California, Los Angeles
 TBA
 03/21/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17541

Monday 3/25 4:10 PM

Paul Irving and Daryl McPadden , Physics, MSU

Group based assessments
 Paul Irving and Daryl McPadden , Physics, MSU
 Group based assessments
 03/25/2019
 4:10 PM  5:00 PM
 C109 Wells Hall
No abstract available.

17492

Wednesday 3/27 4:10 PM

Yash Jhaveri, Institute for Advanced Study

TBA
 Yash Jhaveri, Institute for Advanced Study
 TBA
 03/27/2019
 4:10 PM  5:00 PM
 C517 Wells Hall
No abstract available.

17522

Wednesday 3/27 4:10 PM

Dongsoo Lee

TBA
 Dongsoo Lee
 TBA
 03/27/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

14365

Thursday 3/28 4:10 PM

Ken Ono, Emory University

TBA
 Ken Ono, Emory University
 TBA
 03/28/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17523

Wednesday 4/3 4:10 PM

Brandon Bavier

TBA
 Brandon Bavier
 TBA
 04/03/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17538

Thursday 4/4 2:00 PM

Leonid Chekhov, MSU

TBA
 Leonid Chekhov, MSU
 TBA
 04/04/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
No abstract available.

17510

Monday 4/8 3:00 PM

Mona Merling, University of Pennsylvania

TBA
 Mona Merling, University of Pennsylvania
 TBA
 04/08/2019
 3:00 PM  4:00 PM
 C304 Wells Hall
No abstract available.

17524

Wednesday 4/10 4:10 PM

Joe Melby

TBA
 Joe Melby
 TBA
 04/10/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

17498

Thursday 4/11 2:00 PM

Jennifer Hom, Georgia Tech

TBA
 Jennifer Hom, Georgia Tech
 TBA
 04/11/2019
 2:00 PM  3:00 PM
 C304 Wells Hall
No abstract available.

17525

Wednesday 4/17 4:10 PM

Zhe Zhang

TBA
 Zhe Zhang
 TBA
 04/17/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

15385

Thursday 4/18 4:10 PM

Emmy Murphy, Northwestern University

TBA
 Emmy Murphy, Northwestern University
 TBA
 04/18/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.

15449

Monday 4/22 4:10 PM

Jane Zimmerman, MSU

MTH 103A/B: Experiences from the classroom and future directions
 Jane Zimmerman, MSU
 MTH 103A/B: Experiences from the classroom and future directions
 04/22/2019
 4:10 PM  5:00 PM
 C109 Wells Hall
No abstract available.

14350

Thursday 4/25 4:10 PM

André Neves, University of Chicago

TBA
 André Neves, University of Chicago
 TBA
 04/25/2019
 4:10 PM  5:00 PM
 C304 Wells Hall
No abstract available.
