Colloquium Archives for Academic Year 2017


Math Department Welcome

When: Wed, September 13, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: () -


Approximation Algorithms: Some ancient, some new - the good, the bad and the ugly

When: Wed, September 20, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Samir Khuller (University of Maryland Computer Science ) - https://www.cs.umd.edu/users/samir/
Abstract: NP-complete problems abound in every aspect of our daily lives. One approach is to simply deploy heuristics, but for many of these we do not have any idea as to when the heuristic is effective and when it is not. Approximation algorithms have played a major role in the last three decades in developing a foundation for a better understanding of optimization techniques - greedy algorithms, algorithms based on LinearProgramming (LP) relaxations have paved the way for the design of (in some cases) optimal heuristics. Are these the best ones to use in “typical” instances? Maybe, maybe not.


In this talk we will focus on two specific areas - one is in the use of greedy algorithms for a basic graph problem called connected dominating set, and the other is in the development of LP based algorithms for a basic scheduling problem in the context of data center scheduling.

Faculty Meeting with CMNS Interim Dean, Jerry Wilkinson

When: Wed, September 27, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: (CMNS Dean's Office) -


Binet-Legendre metric and applications of Riemannian results in Finsler geometry

When: Wed, October 4, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Vladimir Matveev (Friedrich-Schiller-Universität Jena ) - http://users.minet.uni-jena.de/~matveev/
Abstract: We introduce a construction that associates a Riemannian metric $g_F$ (called the
Binet-Legendre metric) to a
given Finsler metric $F$ on a smooth manifold $M$. The transformation
$F \mapsto g_F$ is $C^0$-stable and has good
smoothness properties, in contrast to previously considered
constructions. The Riemannian metric $g_F$ also behaves nicely under
conformal or isometric transformations of the Finsler metric $F$ that
makes it a powerful tool in Finsler geometry. We illustrate that by
solving a number of named problems in Finsler geometry. In particular
we extend a classical result of Wang to all dimensions. We answer a
question of Matsumoto about local conformal mapping between two
Berwaldian spaces and use it to investigation of essentially conformally Berwaldian manifolds.
We describe all possible conformal self maps and all self similarities
on a Finsler manifold, generasing the famous result of Obata to Finslerian manifolds. We also classify all compact conformally flat
Finsler manifolds. We solve a conjecture of Deng and Hou on locally
symmetric Finsler spaces. We prove smoothness of isometries of Holder-continuous Finsler metrics. We construct new ``easy to calculate''
conformal and metric invariants of finsler manifolds.
The results are based on the papers arXiv:1104.1647, arXiv:1409.5611,
arXiv:1408.6401, arXiv:1506.08935,
arXiv:1406.2924
partially joint with M. Troyanov (EPF Lausanne) and Yu. Nikolayevsky (Melbourne).

(No colloquium)

When: Wed, October 11, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: General Departmental Meeting () -


No colloquium

When: Wed, October 18, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Departmental Meeting () -


No colloquium

When: Wed, October 25, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Departmental Meeting () -


TBA

When: Wed, November 1, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Xuhua He (UMD) - http://www.math.umd.edu/~xuhuahe/


TBA

When: Wed, November 8, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Pierre-Emmanuel Jabin (UMD) - http://www2.cscamm.umd.edu/~jabin/


TBA

When: Wed, November 15, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Simon Levin (Princeton ) -
Abstract: TBA

TBA

When: Wed, November 29, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Held for Special Lecture (TBA) -


TBA

When: Wed, December 6, 2017 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Held for Special Lecture () -


TBA

When: Wed, January 24, 2018 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Shrawan Kumar (UNC at Chapel Hill) - http://www.unc.edu/math/Faculty/kumar/
Abstract: TBA

Aziz Lecture

When: Wed, February 7, 2018 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Claude Le Bris () -


TBA

When: Wed, March 14, 2018 - 3:15pm
Where: Kirwan Hall 3206
Speaker: Richard Schwartz (Brown University) - http://www.math.brown.edu/~res/