Corpus ID: 124634880

ISOTROPY AND CROSSED TOPOSES

@inproceedings{Funk2012ISOTROPYAC,
  title={ISOTROPY AND CROSSED TOPOSES},
  author={J. Funk and Pieter J. W. Hofstra and B. Steinberg},
  year={2012}
}
In memory of Hugh Millington Abstract. Motivated by constructions in the theory of inverse semigroups and etale groupoids, we dene and investigate the concept of isotropy from a topos-theoretic per- spective. Our main conceptual tool is a monad on the category of grouped toposes. Its algebras correspond to a generalized notion of crossed module, which we call a crossed topos. As an application, we present a topos-theoretic characterization and generaliza- tion of the 'Cliord, fundamental… Expand
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