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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeAug 27th 2015

    The entry Lie algebra extension used to have only a discussion of the fairly exotic topic of classification in nonabelian Lie algebra cohomology. I have now added an Idea-section with some more introductory and more traditional remarks. This could well be expanded much further.

  1. In a short exact sequence 0 -> k -i-> g -p-> b -> 0, the image of p is Im(p) = b, as p is an epimorphism (by exactness im(p) = ker(b -> 0) = b). Previously, the page said Im(p) = 0.


    diff, v12, current

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