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Seminar on Stacks and Groupoids
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\begin{Huge}\textsc{Representable morphisms}
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\begin{Large}\textbf{
 Sebastian Casalaina-Martin}
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University of Colorado at Boulder
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In order to study a stack using techniques from geometry (or commutative algebra), we would like that the stack be as close to a geometric (or algebraic) object as possible.  Unfortunately, our first hope, that the stack be representable by such an object, does not occur for many examples of interest.  In order to define what is meant by ``close to'' a geometric object, we introduce the notion of a (strongly) representable morphism of stacks.  




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Tuesday April 6, 2010

4:00 p.m.

MATH 350

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