Stacks and Groupoids

University of Colorado at Boulder

Seminar on

STACKS AND GROUPOIDS

Spring 2010: Tuesdays 4-5 PM in MATH 350

This is a working seminar meant to introduce algebraic and smooth stacks, groupoids, and orbifolds. The seminar will be held in MATH 350. The mathematics department is at the corner of Colorado Ave and Folsom St. For a map of the campus, click here. For last semester's seminar, click here.

Schedule of upcoming talks:

Click on the title of a talk for the abstract (if available).

January 19	Sebastian Casalaina-Martin	Organizational meeting and review of last semester's seminar
January 26	NO SEMINAR	NO SEMINAR
February 2	Sebastian Casalaina-Martin	Categories fibered in groupoids
February 9	Bart Kastermans	Sets versus classes: why you care (Lecture notes) (Video)
February 16	Sebastian Casalaina-Martin	Categories fibered in groupoids continued
February 23	NO SEMINAR	FACULTY RETREAT
March 2	Graeme Wilkin	Introduction to descent theory
March 9	Graeme Wilkin	Descent theory continued
March 16	NO SEMINAR	NON-COMMUTATIVE GOEMETRY CONFERENCE
March 23	NO SEMINAR	SPRING BREAK
March 30	Sebastian Casalaina-Martin	The isomorphism presheaf and the definition of a stack
April 6	Sebastian Casalaina-Martin	Representable morphisms
April 13	Markus Pflaum	Differentiable stacks
April 20	Markus Pflaum	Differentiable stacks continued
April 27	Eitan Angel	Gerbes

NEXT SPRING'S SEMINAR ON DEFORMATION THEORY

References:

Stacks for Everybody by Fantechi
Algebraic Stacks by Fulton et al.
FGA Explained by Fantechi et al. (First chapter by Vistoli on the arxiv)
Topological and Smooth Stacks by Metzler

Some further references:

The irreducibility of the space of curves of a given genus by Deligne-Mumford
Picard groups of moduli problems by Mumford
Intersection theory on algebraic stacks and their moduli spaces by Vistoli
Introduction to the language of stacks and gerbes by Moerdijk
Orbifolds as groupoids: an introduction by Moerdijk
Sheaves in geometry and logic: a first introduction to topos theory by Mac Lane-Moerdijk
Orbifolds as stacks? by Lerman
Differentiable stacks and gerbes by Behrend and Xu
de Jong's Stack Project

This seminar is being organized by Sebastian Casalaina-Martin and Markus Pflaum. The web page is maintained by Sebastian Caslaina-Martin; it was shamelessly copied from Izzet Coskun's page, which in turn was shamelessly copied from Jason Starr's page, which in turn was shamelessly copied from Ravi Vakil's page, which in turn was shamelessly copied from Pasha Belorousski's page at the University of Michigan.