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Analytical probabilistic approach to the ground state of lattice quantum systems: exact results in terms of a cumulant expansion

Massimo Ostilli·Carlo Presilla
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Abstract

We present a large deviation analysis of a recently proposed probabilistic approach to the study of the ground-state properties of lattice quantum systems. The ground-state energy, as well as the correlation functions in the ground state, are exactly determined as a series expansion in the cumulants of the multiplicities of the potential and hopping energies assumed by the system during its long-time evolution. Once these cumulants are known, even at a finite order, our approach provides the ground state analytically as a function of the Hamiltonian parameters. A scenario of possible applications of this analyticity property is discussed.

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Massimo Ostilli, Carlo Presilla. 2005-04-07. Analytical probabilistic approach to the ground state of lattice quantum systems: exact results in terms of a cumulant expansion. https://doi.org/10.1088/1742-5468%2F2005%2F04%2Fp04007

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