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arXiv · 1807.05299

Orthogonalization of fermion k-body operators and representability

Volker Bach·Robert Rauch
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Abstract

The reduced k-particle density matrix of a density matrix on finite-dimensional, fermion Fock space can be defined as the image under the orthogonal projection in the Hilbert-Schmidt geometry onto the space of k-body observables. A proper understanding of this projection is therefore intimately related to the representability problem, a long-standing open problem in computational quantum chemistry. Given an orthonormal basis in the finite-dimensional one-particle Hilbert space, we explicitly construct an orthonormal basis of the space of Fock space operators which restricts to an orthonormal basis of the space of k-body operators for all k.

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Volker Bach, Robert Rauch. 2019-04-09. Orthogonalization of fermion k-body operators and representability. https://doi.org/10.1103/physreva.99.042109

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