### April 2014

*Dijkgraaf-Witten theory using cohomology with coefficients in Picard groupoids*on Apr 9th at 2:30p.m. in VinH 311

**Amit Sharma**(

*University of Minnesota*)

Dijkgraaf-Witten theory, a gauge theory with nite gauge group, was introduced in a paper of Dijkgraaf and Witten. A detailed description of this theory was ...
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### March 2014

### February 2014

*Organizational Meeting for Study Group*on Feb 21st at 2:30p.m. in VinH 311

**Jeremiah Peterson**(

*University of Minnesota*)

This semester we will be using some of the STS meetings to study basic computations in stable homotopy using the spectrum MU. We will be ...
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### December 2013

*Introduction to discrete Morse theory*on Dec 11th at 2:30p.m. in VinH 20

**Henry Adams**(

*IMA*)

This talk will be an introduction to discrete Morse theory. Whereas standard Morse theory studies smooth functions on a differentiable manifold, discrete Morse theory considers ...
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*Geography of Smooth (Symplectic) 4-Manifolds*on Dec 4th at 2:30p.m. in VinH 20

**Nur Saglam**(

*University of Minnesota*)

We will introduce geography and related botany problems for smooth 4 manifolds. Then we will provide various surgery techniques such as Knot surgery and Luttinger ...
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### November 2013

*Crazy Sock Orbifolds*on Nov 20th at 2:30p.m. in VinH 20

**Jeffrey Bailes**(

*University of Melbourne*)

An orbifold can be thought of as a twisted space. During this talk I'll define an orbifold and hopefully give some other mildly interesting definitions ...
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*Chromatic tower and chromatic convergence*on Nov 15th at 2:30p.m. in VinH 20

**Drew Heard**(

*University of Melbourne*)

The chromatic tower is a tower of localisations with respect to Morava E-theory. The Hopkins-Ravenel chromatic convergence theorem gives conditions for the convergence of this ...
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*Morava E-theory*on Nov 13th at 2:30p.m. in VinH 20

**Drew Heard**(

*University of Melbourne*)

We will review the construction of formal group laws and define the height associated to a formal group law over a finite field. We will ...
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*Configuration spaces, homological stability and applications*on Nov 8th at 2:30p.m. in VinH 20

**TriThang Tran**(

*University of Melbourne*)

The first talk aims to be an introductory talk on how to prove homological stability theorems via an example: the configuration space of the disk. ...
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*Configuration spaces, homological stability and applications*on Nov 6th at 2:30p.m. in VinH 20

**TriThang Tran**(

*University of Melbourne*)

The first talk aims to be an introductory talk on how to prove homological stability theorems via an example: the configuration space of the disk. ...
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### October 2013

*The Cobordism Hypothesis*on Oct 16th at 2:30p.m. in VinH 20

**Amit Sharma**(

*University of Minnesota*)

I will start the first of my two talks on the Cobordism hypothesis by introducing the notion of a bordism. In the first talk I ...
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*Infinity Categories*on Oct 2nd at 2:30p.m. in VinH 20

**Maggie Ewing**(

*University of Minnesota*)

I'm going to try to define basic category theoretic concepts, like functors, limits, etc., for infinity categories. I'm hoping that I'll be able to talk ...
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### September 2013

*Computations of the homotopy groups of spheres*on Sep 20th at 2:30p.m. in VinH 20

**Robert Hank**(

*University of Minnesota*)

We will work through an example that will help us understand the interaction between the transgression and the Steenrod algebra. After this we will begin ...
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*Computations of the homotopy groups of spheres*on Sep 18th at 2:30p.m. in VinH 20

**Robert Hank**(

*University of Minnesota*)

After doing our last cohomology spectral sequence example, we will introduce some of the players in the computations of homotopy groups of spheres. If we ...
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*What is a spectral sequence?*on Sep 13th at 2:30p.m. in VinH 20

**Robert Hank**(

*University of Minnesota*)

We will try to understand what a spectral sequence is and see some example computations using the gadgetry. A special emphasis will be placed on ...
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*What is a spectral sequence?*on Sep 11th at 2:30p.m. in VinH 20

**Robert Hank**(

*University of Minnesota*)

We will try to understand what a spectral sequence is and see some example computations using the gadgetry. A special emphasis will be placed on ...
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