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Quotients of groupoids by an action of a group

Published online by Cambridge University Press:  24 October 2008

John Taylor
Affiliation:
Department of Mathematics, University of the West Indies, Mona, Kingston 7, Jamaica, West Indies

Extract

For any category A and group G there is a category AG of A-objects with G-action. An object of AG is an A-object A together with a group morphism, θA:G → Isom (A, A), of G into the group of invertible A-morphisms AA. A morphism of AG is an A-morphism f: A → B which commutes with the G-action; that is, for each gG, the following diagram commutes.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1988

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