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Monday, September 20, 2021

**Abstract:** (joint work with Yael Karshon) We develop some basic tools of differential geometry for singular spaces. There is a variety of approaches to geometry on singular spaces going back to 1960's. The spaces we work with lie in the intersection of differential spaces of Sikorski and C-infinity schemes of Dubuc. We integrate vector fields to flows and we construct a C-infinity ring analogue of Grothendieck's algebraic de Rham complex. (part 1 of a two part talk, part 2 will be next week)