Internal matrices and applications

Patrick Cassam-Chenaï

Université de Nice Sophia Antipolis

Abstract

We will present the concepts of “internal space and internal matrix” and three applications:
 �	the derivation of CASSCF variational spaces of quantum chemistry, which gives the opportunity to introduce the trinity: algebra, analysis and geometry in mathematics
 �	the possibility to substitute the N-representability problem for p-reduced density matrices by that for p-internal matrices
 �	the definition of the concept of p-orthogonality as a measure of distinguishability between subsets of identical particles.