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arXiv · 0907.3998

High-order Time Expansion Path Integral Ground State

R. Rota·J. Casulleras·F. Mazzanti·J. Boronat
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Abstract

The feasibility of path integral Monte Carlo ground state calculations with very few beads using a high-order short-time Green's function expansion is discussed. An explicit expression of the evolution operator which provides dramatic enhancements in the quality of ground-state wave-functions is examined. The efficiency of the method makes possible to remove the trial wave function and thus obtain completely model-independent results still with a very small number of beads. If a single iteration of the method is used to improve a given model wave function, the result is invariably a shadow-type wave function, whose precise content is provided by the high-order algorithm employed.

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R. Rota, J. Casulleras, F. Mazzanti, J. Boronat. 2009-07-23. High-order Time Expansion Path Integral Ground State. https://doi.org/10.1103/physreve.81.016707

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