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arXiv · 0911.3777

Reduced density matrix of permutational invariant many-body systems

Mario Salerno·Vladislav Popkov
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Abstract

We consider density matrices which are sums of projectors on states spanning irreducible representations of the permutation group of L sites (eigenstates of permutational invariant quantum system with L sites) and construct the reduced density matrix (RDM) for blocks of size n<L by tracing out L-n sites, viewed as environment. Explicit analytic expressions of the elements of the RDM are given in the natural basis and the corresponding spectrum is derived. Results apply to all quantum many-body systems with permutational symmetry for which the mean field theory is exact.

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Mario Salerno, Vladislav Popkov. 2009-11-19. Reduced density matrix of permutational invariant many-body systems. https://arxiv.org/abs/0911.3777

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