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From: "Eduardo J. Dubuc" <edubuc@dm.uba.ar>
To: George Janelidze <janelg@telkomsa.net>
Cc: "Fred E.J. Linton" <fejlinton@usa.net>, categories@mta.ca
Subject: Re: Stone duality for generalized Boolean algebras
Date: Tue, 25 Jan 2011 22:51:57 -0200	[thread overview]
Message-ID: <E1PiVuc-0003mW-PK@mlist.mta.ca> (raw)
In-Reply-To: <E1Pht1k-0003iV-Pq@mlist.mta.ca>

Dear George, I do not think that the answer to Andrej Bauer question is
trivial, as a matter of fact it is not trivial at all. Andrej or any other
able mathematician does not have to know that GBA is equivalent to BA/2.
Furthermore, I feel that Fred Linton bringing into consideration the analogy
with C* algebras is pointing to Andrej some relevant mathematical questions.

greetings  e.d.

George Janelidze wrote:
> Dear Fred,
>
> Please forgive me, but let us distinguish between serious questions and
> trivialities:
>
> Andrej Bauer asked:
>
> "...How exactly does this extend to generalized Boolean algebras?..."
>
> And the answer is trivial (without quotation marks): The category GBA of
> what he called generalized Boolean algebras is dually equivalent to the
> category 1\STONE of pointed Stone spaces. This follows from Stone duality
> (since GBA is equivalent to BA/2), but also extends it: just as BA is a
> non-full subcategory of GBA, STONE can be considered as a non-full
> subcategory of 1\STONE via the functor that adds base points. And this way
> the dual equivalence between GBA and 1\STONE indeed extends the Stone
> duality.
>

...


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  reply	other threads:[~2011-01-26  0:51 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-23 15:38 Fred E.J. Linton
2011-01-24 21:15 ` George Janelidze
2011-01-26  0:51   ` Eduardo J. Dubuc [this message]
2011-01-26 17:19   ` F. William Lawvere
2011-01-27  2:41     ` Eduardo J. Dubuc
  -- strict thread matches above, loose matches on Subject: below --
2011-01-22 18:47 Jeff Egger
2011-01-21 22:39 Fred E.J. Linton
2011-01-21 13:19 Andrej Bauer
2011-01-21 23:06 ` George Janelidze
2011-01-23  4:06 ` Yoshihiro Maruyama

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