Department of

# Mathematics

Seminar Calendar
for events the day of Monday, April 6, 2015.

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events for the
events containing

Questions regarding events or the calendar should be directed to Tori Corkery.
      March 2015             April 2015              May 2015
Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
1  2  3  4  5  6  7             1  2  3  4                   1  2
8  9 10 11 12 13 14    5  6  7  8  9 10 11    3  4  5  6  7  8  9
15 16 17 18 19 20 21   12 13 14 15 16 17 18   10 11 12 13 14 15 16
22 23 24 25 26 27 28   19 20 21 22 23 24 25   17 18 19 20 21 22 23
29 30 31               26 27 28 29 30         24 25 26 27 28 29 30
31


Monday, April 6, 2015

8:00 am in Altgeld Hall,Monday, April 6, 2015

#### Mathematics Graduate School Open House

12:00 pm in 341 AH,Monday, April 6, 2015

#### Stability and Rigidity of Lie Brackets

###### Ivan Struchiner (U São Paulo)

Abstract: I will discuss some rigidity and stability results for geometric structures governed by Lie brackets, namely Lie algebroids and their morphisms. Examples include infinitesimal actions of Lie algebras and flat connections. I will focus on providing clear statements of the main results. If time permits, I will discuss some of the ideas in the proofs.

4:00 pm in 245 Altgeld Hall,Monday, April 6, 2015

#### Why topology is geometry in dimension 3

###### Nathan Dunfield (Department of Mathematics, University of Illinois at Urbana-Champaign)

Abstract: After setting the stage by sketching a few facts about the topology and geometry of surfaces, I will explain why the study of the topology of 3-dimensional manifolds is inextricably linked to the study of homogenous geometries such as Euclidean, spherical, and (especially) hyperbolic geometry. This perspective, introduced by Thurston in the 1980s, was stunningly confirmed in the early 2000s by Perelman's deep work using geometric PDEs, and lead to the solution of the 100 year-old Poincaré conjecture. I will hint at how this perspective brings other areas of mathematics, specifically algebraic geometry and number theory, to bear on problems that initially appear purely topological in nature, and conclude with a live computer demonstration of how geometry can be used to tell different 3-manifolds apart in practice.

5:00 pm in Altgeld Hall 241,Monday, April 6, 2015

#### Approximation properties for quantum groups, monoidal equivalence, and Drinfeld doubles. Part 2

###### Michael Brannan (UIUC Math)

Abstract: We continue from last monday.