## Colloquium

### Numerical methods for electronic structure calculation

##### Thursday, April 17, 2014 at 3:30p.m.

**Eric Cances** (*Ecole des Ponts Paris Tech*)

**Abstract:**Electronic structure calculation has become an essential tool in chemistry, condensed matter physics, molecular biology, materials science, and nanosciences. It is also an inexhaustible source of exciting mathematical and numerical issues. In this talk, I will focus on two standard electronic structure models, namely the N-body Schrödinger equation, and the Kohn-Sham formulation of the Density Functional Theory (DFT). The former model is a (very) high-dimensional linear elliptic eigenvalue problem. It is out of reach of standard numerical methods, but its solutions can be numerically approximated either by stochastic methods, or by sparse tensor product techniques. The Kohn-Sham model is a constrained optimization problem, whose Euler-Lagrange equations have the form of a coupled system of nonlinear elliptic eigenvalue problems. Recent progress has been made in the analysis of these mathematical models and of the associated numerical methods, which paves the road to high-fidelity numerical simulations (with a posteriori error bounds) of the electronic structure of large molecular systems.

### Monday, 14 April 2014

#### Topology Seminar

*Persistent Sheaves for Stratified Maps*at 2:30p.m. in VinH 311

**Amit Patel**(

*University of Minnesota (IMA)*)

Given a stratified map f : X -> Y, we may study the homology (relative homology) of its fibers by studying its Leray cosheaf (sheaf), ...
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#### Automorphic Forms and Number Theory

### Tuesday, 15 April 2014

#### IMA Postdoc Seminar

#### Math Biology Seminar

*Self‐sustained network dynamics caused by inhibitory nodes*at 2:30p.m. in VinH 364

**Juan Restrepo**(

*U of Colorado, Boulder, Applied Mathematics*)

Experimental signatures of critical dynamics in functional brain networks have been successfully modeled using networks of simple excitable systems. However, these models do not typically ...
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### Wednesday, 16 April 2014

#### PDE Seminar

*On the boundary value problems for parabolic non-divergence equations with coefficients measurable in time*at 3:35p.m. in VinH 313

**Alexander Nazarov**(

*St Petersburg State University*)

We consider the Dirichlet problem for non-divergence parabolic equation with discontinuous in $t$ coefficients in a half-space and in a wedge. The main result is ...
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#### Student Symplectic and Low Dimensional Topology Seminar

*Symplectic structure on the space of knots*at 3:35p.m. in VinH 301

**Denis Bashkirov**(

*University of Minnesota*)

J.Marsden and A.Weinstein had shown how to equip the space of codimension-2 submanifolds of a Riemannian manifold with a symplectic structure. We'll discuss this construction ...
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### Thursday, 17 April 2014

#### Math Club Seminar

*The Beauty of the Mandelbrot Set*at 12:20p.m. in Vincent Hall 570

**Dalton Schutte**(

*University of Minnesota*)

I will establish some elementary concepts from complex dynamics before using Julia sets to define the Mandelbrot set and offer some of its interesting properties.

#### Bobkov Student Seminar

*De Bruijn's Identity - a continuation*at 1:15p.m. in Lind Hall 401

**Qiushi Li**(

*University of Minnesota*)

#### Student Combinatorics Seminar

*Categorification of the polynomial ring Z[x]*at 1:25p.m. in Ford Hall 155

**Radmila Sazdanovic**(

*North Carolina State University and IMA*)

We develop a diagrammatic categorification of the polynomial ring Z[x] based on the geometrically defined graded algebra and show how to lift various operations on ...
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#### Differential Geometry / Symplectic Topology Seminar

*HMS, Constructible Sheaves, Lagrangian Skeleta, and VGIT*at 1:30p.m. in VinH 570

**Professor David Favero**(

*University of Alberta*)

I will discuss homological mirror symmetry from the perspective of Lagrangian skeleta and constructible sheaves following Fang, Liu, Treumann, and Zaslow. I will discuss an ...
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#### Colloquium

*Numerical methods for electronic structure calculation*at 3:30p.m. in Vin H 16

**Eric Cances**(

*Ecole des Ponts Paris Tech*)

Electronic structure calculation has become an essential tool in chemistry, condensed matter physics, molecular biology, materials science, and nanosciences. It is also an inexhaustible source ...
(more)

### Friday, 18 April 2014

#### Commutative Algebra Seminar

*Euler-Koszul homology and hypergeometric systems, VII*at 1:25p.m. in VinH 203A

**Christine Berkesch Zamaere**(

*University of Minnesota*)

The solutions of hypergeometric systems of differential equations are among the most studied functions in mathematics. Recently, a change of variables introduced by Gelfand, Kapranov, ...
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#### Probability Seminar

*Statistics of gaps within the range of a random walk*at 2:30p.m. in VH 207

**Vlad Vysotsky**(

*Arizona State University and St. Petersburg Division of Steklov Institute*)

Consider a centered random walk with a finite variance in dimension one. We are interested in sparseness of the range of the walk by time ...
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#### Combinatorics Seminar

*A Robinson-Schendsted correspondence on complex reflection groups G(r,p,n)*at 3:35p.m. in VinH 570

**aBa Mbirika**(

*Wisconsin-Eau Claire*)

The classical Robinson-Schensted algorithm establishes a bijection between permutations in the symmetric group S_n and ordered pairs of same-shape standard Young tableaux of size n. ...
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#### MFM Seminar

*Price Discovery, Volatility Spillovers and Adequacy of Speculation when Spot Prices are Stationary: The Case of U.S. Dairy Markets*at 5:30p.m. in VinH 16

**Prof. Marin Bozic**(

*Assistant Professor in Dairy Foods Marketing Economics in the Department of Applied Economics at the University of Minnesota.*)

This article contributes to the debate on time series properties of commodity cash and futures markets and the impact of speculation on commodity futures markets. ...
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### Seminars Not Meeting This Week

**Algeba Reading Seminar**on Thursday at 2:00p.m. in VinH 2.

**Algebraic Geometry**on Wednesday at 2:30a.m. in VinH 113.

**Climate Seminar**on Tuesday at 11:15a.m. in Lind Hall 305.

**Cockburn's Seminar**on Monday at 8:00a.m. in VinH 570.

**Graduate Student Seminar**on Friday at 12:15p.m. in VinH 16.

**IMA Public Lectures**on Wednesday at 7:00p.m. in various locations.

**IMA Workshops: Geometric and Topological Methods in Variational Calculus**on Thursday at 10:30a.m. in Lind Hall 305.

**Industrial Problems Seminar**on Friday at 1:25a.m. in Lind Hall 305.

**Introduction to Research**on Friday at 12:20p.m. in VinH 2.

**Jr. Colloquium**on Wednesday at 12:20p.m. in VinH 16.

**Lie Theory Seminar**on Friday at 3:40p.m. in VinH 211.

**Math Physics Seminar**on Monday at 11:15a.m. in VinH 570.

**Postdoc Seminar**on Thursday at 4:30p.m. in VinH 570.

**Reitich Research Group**on Friday at 3:30p.m. in VinH 20.

**SIAM Student reading group Seminar**on Wednesday at 12:30p.m. in VinH 570.

**SIAM Student Seminar**on Wednesday at 1:20a.m. in VinH 570.

**Special Events and Seminars**on Monday at 12:00p.m. in VinH.

**Student Number Theory Seminar**on Tuesday at 1:15p.m. in VinH 570.

**Student Stochastic Seminar**on Friday at 1:25a.m. in VinH 570.

**Student Topology Seminar**on Wednesday at 2:30p.m. in VinH 311.