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Graduate Student Geometry-Topology Seminar

Wednesday, February 15, 2023 - 12:00pm

Colin Fourel

ENS Lyon/UPenn


University of Pennsylvania


The starting point and first part of this talk will be based on the observation that the residue theorem of complex analysis can be formulated and proven without any reference to homotopy theoretic concepts (modulo a change in the definition of simple connectedness). This observation leads to natural, but in some cases rather nontrivial, questions about the algebraic topology of open subsets of the plane, that I will address in a second part.