May 5, 2008

Martin Olsson

Why groupoids?

For a student learning algebraic geometry, it can sometimes seem as if the subject in its modern formulation is overwhelmingly abstract. While we may be interested in solutions to polynomial equations, we study schemes, and then the much more abstract notions of algebraic space and stacks. I will try to motivate in this talk why these more general objects are natural to consider, and even indispensable.

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