From: Michael Barr <barr@math.mcgill.ca>
To: Categories list <categories@mta.ca>
Subject: Homomorphisms on Z^n
Date: Fri, 14 Sep 2007 08:34:33 -0400 (EDT) [thread overview]
Message-ID: <E1IWL3l-00052x-AM@mailserv.mta.ca> (raw)
Many years ago (at least 45) Harrison mentioned to me that for any n
(including infinite cardinals), Hom(Z^n,Z) = n.Z, in other words the
Z-dual of the product is the sum. This is obviously a very special
property of Z, almost the negation of injectivity. Has anyone on this
list ever seen this before and can give me a reference?
Michael
next reply other threads:[~2007-09-14 12:34 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-14 12:34 Michael Barr [this message]
2007-09-15 9:02 Ronnie Brown
2007-09-18 16:53 Stephen Urban Chase
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