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From: Gabor Lukacs <lukacs@mathstat.yorku.ca>
To: <categories@mta.ca>
Subject: Compact subsets of k-spaces (without separation axioms)
Date: Sun, 15 Feb 2004 08:47:57 -0500 (EST)	[thread overview]
Message-ID: <Pine.A41.4.31.0402150847070.62202-100000@pascal.math.yorku.ca> (raw)

Dear Topologists, Categorists and Categorical Topologists,


It is well-known that for a *Hausdorff* topological space X, its
k-ification kX and X have the same compact subspaces.

It is also well-known that when we assume no separation axioms, X and kX
have the same k-continuous maps (i.e. maps f:X -->Y such that ft is
continuous for every "test-function" t: K --> X, where K is a compact
Hausdorff space).

I was wondering if anyone knows whether the first statement is true
*without separation axioms*, i.e., whether for every topological space X,
its k-ification kX and X have the same compact subspaces.

I would very much appreciate any suggestion, reference or counterexample.


Gabor Lukacs





             reply	other threads:[~2004-02-15 13:47 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-02-15 13:47 Gabor Lukacs [this message]
2004-02-16 10:30 ` Martin Escardo

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