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From: Michael Barr <mbarr@math.mcgill.ca>
To: Categories list <categories@mta.ca>
Subject: Construction of a real closure
Date: Thu, 4 May 2006 11:22:10 -0400 (EDT)	[thread overview]
Message-ID: <34794.4216955968$1241019210@news.gmane.org> (raw)

Is there a reference for the fact that a countable decidably ordered field
has a constructable (and decidably ordered) real closure?

Maybe 20 years ago, an undergraduate did a project under my supervision
proving exactly that (although the proofs are not constructive). While I
don't think it would prove feasible for actual computation, the fact that
it exists is interesting.  Finally, I have looked more closely at it and
if it is not known, I think it publishable.  Unfortunately, the student
(who was a Commonwealth Fellow at Cambridge) lost interest in math and is
doing other things.  But I think I know how to get in touch with him.

Michael




             reply	other threads:[~2006-05-04 15:22 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-05-04 15:22 Michael Barr [this message]
2006-05-04 22:20 Marta Bunge
2006-05-04 22:20 Marta Bunge
2006-05-04 23:28 Michael Barr
2006-05-05  2:14 Phil Scott
2006-05-05 12:22 Michael Barr
2006-05-05 13:30 Marta Bunge
2006-05-05 13:45 Peter Freyd
2006-05-05 14:55 John Baez
2006-05-05 20:34 Peter Freyd
2006-05-06  2:24 Eduardo Dubuc
2006-05-06 13:53 Michael Barr
2006-05-07 20:28 Marta Bunge

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