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Bases in Systems of Simplices and Chambers

Tatiana Alekseyevskaya
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Abstract

We consider a finite set $E$ of points in the $n$-dimensional affine space and two sets of objects that are generated by the set $E$: the system $Σ$ of $n$-dimensional simplices with vertices in $E$ and the system $Γ$ of chambers. The incidence matrix $A= \parallel a_{σ, γ}\parallel$, $σ\in Σ$, $γ\in Γ$, induces the notion of linear independence among simplices (and among chambers). We present an algorithm of construction of bases of simplices (and bases of chambers). For the case $n=2$ such an algorithm was described in the author's paper {\em Combinatorial bases in systems of simplices and chambers} (Discrete Mathematics 157 (1996) 15--37). However, the case of $n$-dimensional space required a different technique. It is also proved that the constructed bases of simplices are geometrical.

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Tatiana Alekseyevskaya. 1997-07-02. Bases in Systems of Simplices and Chambers. https://arxiv.org/abs/math/9707218

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