2024-06-03

612: Simplicial Map

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definition of simplicial map

Topics


About: vectors space

The table of contents of this article


Starting Context



Target Context


  • The reader will have a definition of simplicial map.

Orientation


There is a list of definitions discussed so far in this site.

There is a list of propositions discussed so far in this site.


Main Body


1: Structured Description


Here is the rules of Structured Description.

Entities:
\( V_1\): \(\in \{\text{ the real vectors spaces }\}\)
\( V_2\): \(\in \{\text{ the real vectors spaces }\}\)
\( C_1\): \(\in \{\text{ the simplicial complexes on } V_1\}\)
\( C_2\): \(\in \{\text{ the simplicial complexes on } V_2\}\)
\(*f\): \(: Vert C_1 \to Vert C_2\)
//

Conditions:
\(\forall \{p_0, ..., p_n\} \subseteq Vert C_1 \text{ such that } \{p_0, ..., p_n\} \text{ spans a simplex in } C_1 (\{f (p_0), ..., f (p_n)\} \text{ spans a simplex in } C_2)\).
//


2: Natural Language Description


For any real vectors spaces, \(V_1, V_2\), and any simplicial complexes, \(C_1\), on \(V_1\) and \(C_2\), on \(V_2\), any map, \(f: Vert C_1 \to Vert C_2\), such that for each \(\{p_0, ..., p_n\} \subseteq Vert C_1\) that spans a simplex in \(C_1\), \(\{f (p_0), ..., f (p_n)\}\) spans a simplex in \(C_2\)


3: Note


"\(\{p_0, ..., p_n\}\) spans a simplex in \(C_1\)" is not equal to '\([p_0, ..., p_n]\) is a simplex in \(C_1\)' when \(\{p_0, ..., p_n\}\) contains some duplications, but supposing that the duplications have been removed, they are equal by the proposition that for any simplicial complex, each vertex of each simplex that is on any another simplex is a vertex of the latter simplex: each \(p_j\) is on the spanned simplex, so, \(p_j\) is a vertex of the simplex, and the spanned simplex is nothing but \([p_0, ..., p_n]\). "\(\{f (p_0), ..., f (p_n)\}\) spans a simplex in \(C_2\)" is likewise.


References


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