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Transcript
connected im kleinen∗
Mathprof†
2013-03-21 20:40:23
A topological space X is connected im kleinen at a point x if every open set
U containing x contains an open set V containing x such that if y is a point of
V , then there is a connected subset of U containing {x, y}.
Another way to say this is that X is connected im kleinen at a point x if x has
a neighborhood base of connected sets (not necessarily open).
A locally connected space is connected im kleinen at each point.
A space can be connected im kleinen at a point but not locally connected at
the point.
If a topological space is connected im kleinen at each point, then it is locally
connected.
References
[1] S. Willard, General Topology, Addison-Wesley, Publishing Company, 1970.
[2] J.G. Hocking, G.S. Young, Topology, Dover Pubs, 1988, republication of
1961 Addison-Wesley edition.
∗ hConnectedImKleineni created: h2013-03-21i by: hMathprofi version: h38000i Privacy
setting: h1i hDefinitioni h54D05i
† This text is available under the Creative Commons Attribution/Share-Alike License 3.0.
You can reuse this document or portions thereof only if you do so under terms that are
compatible with the CC-BY-SA license.
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