connected im kleinen
A topological space is connected im kleinen at a point if every open set containing contains an open set containing such that if is a point of , then there is a connected subset of containing .
Another way to say this is that is connected im kleinen at a point if 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 locallyconnected.
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.