Peter Johnstone Lectures: Some aspects of Topos Theory
timetable:
Mon 19 Apr, 14:30 - 16:30, Aula Dini
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Toposes as categories of spaces
speaker: Peter Johnstone (University of Cambridge)abstract: Although every Grothendieck topos is a generalized space, there are some which can also be considered as "categories of spaces", in that objects within the topos have at least some topological attributes. In this lecture we discuss how to recognize when a given topos is a category of spaces: to some extent, this may be derived from its "external" topological properties, as discussed in Lecture 1, but it also seems to involve an additional structure, which may be conveniently encoded by a non-full subcategory of "fibrewise discrete" morphisms, also known as a calibration. We show how this extra structure may be found in several key examples, including the topos of simplicial sets.
timetable:
Mon 19 Apr, 14:30 - 16:30, Aula Dini
<< Go back