Covering morphisms of groupoids, derived modules and a 1-dimensional Relative Hurewicz Theorem∗
نویسنده
چکیده
We fill a lacuna in the literature by giving a version in dimension 1 of the Relative Hurewicz Theorem, and relate this to abelianisations of groupoids, covering spaces, covering morphisms of groupoids, and Crowell’s notion of derived modules.
منابع مشابه
Triadic van Kampen and Hurewicz Theorems∗
In [BH5] it is shown how the Relative Hurewicz Theorem follows from a Generalised Van Kampen Theorem (GVKT) for the fundamental crossed complex of a filtered space, and in [BL3] it is shown how a new multirelative Hurewicz Theorem follows from a GVKT for the fundamental cat-group of an n-cube of spaces. The purpose of this paper is to advertise and explain some implications and special cases of...
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