Difference between revisions of "Vertex set of an abstract simplicial complex"

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(Created page with "{{Stub page|grade=E|msg=See Abstract simplicial complex, same stuff. Needs another reference. See what Books:Combinatorial Algebraic Topology - Dmitry Kozlov has to sa...")
 
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: '''Warning: ''' not to be confused with the [[vertex scheme of an abstract simplicial complex]]
 
: '''Warning: ''' not to be confused with the [[vertex scheme of an abstract simplicial complex]]
 
__TOC__
 
__TOC__
==Definition==
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==[[/Definition|Definition]]==
Let {{M|\mathcal{S} }} be a [[abstract simplicial complex]], we define the ''vertex set'' of {{M|\mathcal{S} }} as follows{{rEOATJRM}}:
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{{/Definition}}
* {{MM|V_\mathcal{S}:\eq\bigcup_{A\in\{B\in\mathcal{S}\ \vert\ \vert B\vert\eq 1 \} } A}}
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'''Note: ''' we do not usually distinguish between {{M|v\in V_\mathcal{S} }} and {{M|\{v\}\in\mathcal{S} }}<ref name="EOATJRM"/>, they are [[notionally identified]].
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==See next==
 
==See next==
 
* {{link|Vertex scheme|abstract simplicial complex}}
 
* {{link|Vertex scheme|abstract simplicial complex}}

Latest revision as of 11:38, 19 February 2017

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See Abstract simplicial complex, same stuff. Needs another reference. See what Books:Combinatorial Algebraic Topology - Dmitry Kozlov has to say. Alec (talk) 11:34, 19 February 2017 (UTC)
Warning: not to be confused with the vertex scheme of an abstract simplicial complex

Definition

Let [ilmath]\mathcal{S} [/ilmath] be a abstract simplicial complex, we define the vertex set of [ilmath]\mathcal{S} [/ilmath], denoted as just [ilmath]V[/ilmath] or [ilmath]V_\mathcal{S} [/ilmath], as follows[1]:

  • [math]V_\mathcal{S}:\eq\bigcup_{A\in\{B\in\mathcal{S}\ \vert\ \vert B\vert\eq 1 \} } A[/math] - the union of all one-point sets in [ilmath]\mathcal{S} [/ilmath]

Note: we do not usually distinguish between [ilmath]v\in V_\mathcal{S} [/ilmath] and [ilmath]\{v\}\in\mathcal{S} [/ilmath][1], they are notionally identified.

See next

References

  1. 1.0 1.1 Elements of Algebraic Topology - James R. Munkres