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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJun 22nd 2010
    • (edited Jun 22nd 2010)

    reformatted the entry group a little, expanded the Examples-section a little and then pasted in the group-related “counterexamples” from counterexamples in algebra. Mainly to indicate how I think this latter entry should eventually be used to improve the entries that it refers to.

    • CommentRowNumber2.
    • CommentAuthorTobyBartels
    • CommentTimeJun 23rd 2010

    I removed the counterexample which was not about group theory (and clarified the header in counterexamples in algebra).

    • CommentRowNumber3.
    • CommentAuthorjesuslop
    • CommentTimeDec 21st 2019

    Minor correction, about “The reason is that two functors…” to change that the η h\eta_h natural transformation is between the delooped version of the parallel group homomorphisms, instead of the homomorphisms themselves.

    diff, v62, current

    • CommentRowNumber4.
    • CommentAuthorbezem
    • CommentTimeJan 27th 2020
    Why is the inverse operation not part of the structure of a group (instead of existence of inverses as a property of a monoid)?
    For a topological group it is, and the inverse operation is required to be continuous.
    • CommentRowNumber5.
    • CommentAuthorTodd_Trimble
    • CommentTimeJan 27th 2020

    Yes, the definition section is arguably a little lacking there, even though the article redeems itself later, down in Internalization. So I’ve fixed it along these lines.

    diff, v63, current

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