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Results tagged with gr.group-theory
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user 184
Questions about the branch of algebra that deals with groups.
7
votes
Extension problem
The subtlety is in when two extensions are considered the same, in other words what are the morphisms of extension? There are different reasonable answers. For example a morphism could just be a morph …
- 27.5k
10
votes
Accepted
Classifying Space of a Group Extension
Yes. The principal bundles are the same and your guess that $BA$ is an abelian group is exactly right. A good reference for this story, and of Segal's result that David Roberts quotes, is Segal's pape …
- 27.5k