Re: Sheaves and the empty set

From: Kira Yamato <kirakun@xxxxxxxxxxxxx>
Date: Fri, 18 May 2007 06:37:29 -0400

On 2007-05-18 04:53:33 -0400, Jose Capco <cliomseerg@xxxxxxxxxxxxxxxxxxxxxxxxx> said:

Dear NG,

We know very well that if F is a sheaf of rings/groups, then
F(emptyset)=the zero ring/groups..

Suppose X is any topological space. For every open set U in X, define
F(U) = Z
where Z is the ring of integers. Define all restriction maps to be the identity map on Z.

Is F a sheaf?

--

-kira

.

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