Group-2-groupoids and 2G-crossed modules

Abstract

In this paper, we introduce the notion of a group-2-groupoid as a group object in the category of 2-groupoids. We also obtain a 2G-crossed module by using the structure of a group-2-groupoid. Then we prove that the  category Gp2Gd of group-2-groupoids and the category 2GXMod of 2G-crossed modules are equivalent.

Keywords

• group-2-groupoid,2G-crossed module

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