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From: Andrej Bauer <andrej.bauer@andrej.com>
To: Steve Vickers <s.j.vickers@cs.bham.ac.uk>
Cc: zoran skoda <zskoda@gmail.com>, categories list <categories@mta.ca>
Subject: Re: A conditon on maps between sheaves
Date: Sun, 27 Mar 2011 20:27:12 +0200	[thread overview]
Message-ID: <E1Q3wqF-000057-Gr@mlist.mta.ca> (raw)
In-Reply-To: <E1PzT6i-0000oV-C9@mlist.mta.ca>

Steve Vickers wrote:
> For example: take B to be the circle and E' its Moebius double cover,
> which has no global sections. Then for every x in B you can take U = B
> and your condition holds vacuously for any f whatsoever.
>
> If E = E'+E' then the codiagonal f has your property but is not mono.

I apologize for the noise, I got my conditions all wrong when I tried
to "optimize" them for the categories list. As it turns out my
condition means that I have a map of etale spaces which is bijective
on fibers (and the spaces in question are Hausdorff locally compact).
So is there a name for that other than "bijective on fibers"?

With kind regards,

Andrej


[For admin and other information see: http://www.mta.ca/~cat-dist/ ]


  reply	other threads:[~2011-03-27 18:27 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-03-12  1:33 Andrej Bauer
2011-03-13 16:25 ` zoran skoda
2011-03-14 14:27   ` Steve Vickers
2011-03-27 18:27     ` Andrej Bauer [this message]
2011-03-28  9:40       ` Prof. Peter Johnstone

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