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From: Jeff Egger <jeffegger@yahoo.ca>
To: categories@mta.ca, Bill Rowan <rowan@synergy.transbay.net>
Subject: Re: Group and abelian group objects in the category of Kelley spaces
Date: Mon, 29 Sep 2008 03:36:27 -0700 (PDT)	[thread overview]
Message-ID: <E1KkI6P-0007Ka-M4@mailserv.mta.ca> (raw)

> if we have an (abelian, say)
> topological group, there is a natural uniform topology on
> the group such
> that the operations are uniformly continuous.  Does the
> same hold for
> abelian group objects in the category of Kelley spaces?

As others have already noted, the answer is no.  One possible
solution (assuming you regard this as a defect) is to apply
the idea implicit in the definition of Kelley space, not to
the category of all topological spaces, but to that of all
Tychonov (=uniformisable) spaces.  What results is a cartesian
closed category (that of "k_R-Tychonov spaces") with somewhat
different properties; a group in this category is tautologously
uniformisable and, if I recall correctly, is also true that the
operations are uniformly continuous.  Gabor Lukacs has studied
these things and spoken about them at several conferences.

Cheers,
Jeff.




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             reply	other threads:[~2008-09-29 10:36 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-29 10:36 Jeff Egger [this message]
  -- strict thread matches above, loose matches on Subject: below --
2008-09-29 15:19 wlawvere
2008-09-28 23:10 Martin Escardo
2008-09-28 14:19 Michael Barr
2008-09-26  4:46 Bill Rowan

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