Talk:Perfect map

Untitled

Could someone please fix up some notation (such as writing p: X->Y properly and writing the inverse of p properly)

Thankyou Topology Expert (talk) 12:06, 13 June 2008 (UTC)[reply]

I do not believe that 10 or 11 are true as they read. Counterexamples:

10. If F is a closed subspace of X, then the inclusion if F in X is perfect, but it is not a quotient map.

11. Let G=Z act on X=R by translations. Then the projection from R to R/Z is not perfect. (For example, the kernel is not compact...) — Preceding unsigned comment added by 24.222.162.70 (talk) 02:14, 14 March 2012 (UTC)[reply]

Actually, I believe 10 and 11 are correct.

Ad 10. The definition requires map to be surjective Ad 11. Z is not a compact group. --89.77.121.156 (talk) 21:53, 22 August 2014 (UTC)[reply]

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