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arXiv · 0709.3951

Geometric Measure of Indistinguishability for Groups of Identical Particles

Patrick Cassam-Chenaï
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Abstract

The concept of p-orthogonality (1=< p =< n) between n-particle states is introduced. It generalizes common orthogonality, which is equivalent to n-orthogonality, and strong orthogonality between fermionic states, which is equivalent to 1-orthogonality. Within the class of non p-orthogonal states a finer measure of non p-orthogonality is provided by Araki's angles between p-internal spaces. The p-orthogonality concept is a geometric measure of indistinguishability that is independent of the representation chosen for the quantum states. It induces a new hierarchy of approximations for group function methods. The simplifications that occur in the calculation of matrix elements between p-orthogonal group functions are presented.

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Patrick Cassam-Chenaï. 2007-09-25. Geometric Measure of Indistinguishability for Groups of Identical Particles. https://doi.org/10.1103/physreva.77.032103

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