| Date |
Speaker |
Title/Abstract |
| 01/25 |
Artur Jackson |
Geometry of Orbifolds
Orbifolds are topological spaces which are largely similar to
manifolds outside of some singular points, whose neighborhoods
can be modeled by quotients of Euclidean space by finite
isometry groups. Such spaces abound in mathematics and
physics, e.g., moduli spaces of curves and in string theory.
This talk will sketch the construction of these mildly singular spaces
(which includes carrying around a heap of extra data).
|
| 01/31 |
Nick Miller |
A Brief Glimpse of Grothendieck Topologies
A Grothendieck topology is a topology that one can put on a
category C which generalizes and gives explicit axioms for the
notion of an open cover. In this talk I will attempt to
motivate the definition and use of Grothendieck topologies
past the standard "Grothendieck thought about it so you should
too", and show some of the consequences of using such a
categorical construction. In particular we will define the
Étale Topology and briefly discuss how this provides us with
a robust cohomology theory.
|
| 02/07 |
Artur Jackson |
Geometry of Orbifolds II: Metrics, Connections and
Universality
In this talk we'll take a pedestrian approach to
(defining and) constructing differentiable maps between orbifolds. This will
lead us to the notion of ``orbibundles'' and automatically
provide us with standard geometric gadgets such as metrics and
connections. We will also make an attempt at using these
orbibundles to produce objects solving universal problems,
e.g., in moduli theory.
|
| 02/15 |
Tamás Darvas |
Chern classes from the point of view of differential
geometry
There are many approaches one can take in defining Chern
classes of vector bundles. In this talk we introduce these
invariants from the point of view of differential geometry and
we will discuss a limited amount of applications due to time
constraints. Students with an understanding of differential
geometry at the level of MA562 should be able to follow the
talk for the most part. |
| TBA |
Andrés Figueroa |
Geometric Invariant Theory and GIT Quotients
[abstract]
|
| TBA |
Artur Jackson |
Introduction to Stacks in Geometry
We'll quickly recall some background topics in geometry, e.g.,
principle G-bundles, and sheaves. We will then immediately
motivate geometric stacks in a very lucid manner. If time
permits the talk may touch on the topic of representing
orbifolds as Deligne-Mumford stacks.
|