Difference between revisions of "Disconnected (topology)"
From Maths
(Created page with "{{Stub page|grade=C|msg=There's not much more to be said, but it does meet the defining criteria for a stub page, hence this}} : '''Note: ''' much more information may be foun...") |
(No difference)
|
Revision as of 22:13, 30 September 2016
Stub grade: C
This page is a stub
This page is a stub, so it contains little or minimal information and is on a to-do list for being expanded.The message provided is:
There's not much more to be said, but it does meet the defining criteria for a stub page, hence this
- Note: much more information may be found on the connected page, this page exists just to document disconnectedness.
Contents
Definition
A topological space, [ilmath](X,\mathcal{ J })[/ilmath], is said to be disconnected if[1]:
- [ilmath]\exists U,V\in\mathcal{J}[U\ne\emptyset\wedge V\neq\emptyset\wedge V\cap U=\emptyset\wedge U\cup V=X][/ilmath], in words "if there exists a pair of disjoint and non-empty open sets, [ilmath]U[/ilmath] and [ilmath]V[/ilmath], such that their union is [ilmath]X[/ilmath]"
In this case, [ilmath]U[/ilmath] and [ilmath]V[/ilmath] are said to disconnect [ilmath]X[/ilmath][1] and are sometimes called a separation of [ilmath]X[/ilmath].
See also
- Connected - a space is connected if it is not disconnected
- Much more information is available on that page, this is simply a supporting page
References
|