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semilocally simply connected (Definition)

A topological space $ X$ is semilocally simply connected if, for every point $ x \in X$, there exists a neighborhood $ U$ of $ x$ such that the map of fundamental groups

$\displaystyle \pi_1(U,x) \longrightarrow \pi_1(X,x) $
induced by the inclusion map $ U \hookrightarrow X$ is the trivial homomorphism.

A topological space $ X$ is connected, locally path connected, and semilocally simply connected if and only if it has a universal cover.



"semilocally simply connected" is owned by djao.
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See Also: connected, simply connected, connected space, locally connected

Other names:  semilocally 1-connected, locally relatively simply connected

Attachments:
example of a space that is not semilocally simply connected (Example) by mathcam
example of a semilocally simply connected space which is not locally simply connected (Example) by antonio
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Cross-references: universal cover, locally path connected, connected, homomorphism, inclusion map, induced, fundamental groups, map, neighborhood, point, topological space
There are 3 references to this entry.

This is version 3 of semilocally simply connected, born on 2002-05-17, modified 2003-03-13.
Object id is 2911, canonical name is SemilocallySimplyConnected.
Accessed 3845 times total.

Classification:
AMS MSC54D05 (General topology :: Fairly general properties :: Connected and locally connected spaces )
 57M10 (Manifolds and cell complexes :: Low-dimensional topology :: Covering spaces)

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