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Lindelöf space (Definition)

Definition

A topological space is said to be Lindelöf if every open cover has a countable subcover.

Notes

A second-countable space is Lindelöf. A compact space is Lindelöf.

A regular Lindelöf space is normal.

$F_\sigma$ sets in Lindelöf spaces are Lindelöf. Continuous images of Lindelöf spaces are Lindelöf.

A Lindelöf space is compact if and only if it is countably compact.




"Lindelöf space" is owned by yark. [ full author list (2) | owner history (1) ]
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See Also: second countable, separable space, compact, Lindelöf theorem, a compact metric space is second countable, Ernst Lindelöf

Also defines:  Lindelöf, Lindelöf property
Keywords:  topology
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Cross-references: countably compact, images, continuous, compact, second-countable, subcover, countable, open cover, topological space
There are 10 references to this entry.

This is version 7 of Lindelöf space, born on 2002-01-04, modified 2007-05-23.
Object id is 1226, canonical name is Lindelof.
Accessed 7067 times total.

Classification:
AMS MSC54D20 (General topology :: Fairly general properties :: Noncompact covering properties )

Pending Errata and Addenda
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Discussion
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relation with 2nd countable by drini on 2002-02-18 17:53:49
being 2nd countable
is a sufficeitn condition for being
lindeloff
 f
G -----> H G
p \ /_ ----- ~ f(G)
 \ / f ker f
 G/ker f 
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