My blog post has a hole. I am not convinced by Paul's answer on Mathoverflow (perhaps I just have to work out the details which Paul left out). So this leaves the question: is every mono in the category of groups regular, constructively speaking? With kind regards, Andrej On Fri, Jun 22, 2012 at 9:19 AM, Paul Taylor <pt12@paultaylor.eu> wrote:
Mike Barr said
Somewhere I have seen a proof that all monics in the category of groups are regular.
Somebody asked this question a while back on MathOverflow and I gave the following proof, which is both constructive and more explicit than the replies that have been given here.
http://mathoverflow.net/questions/41208/are-all-group-monomorphisms-regular-...
Paul Taylor
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