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Quantum Monte Carlo Methods for Nuclei at Finite Temperature

Y. Alhassid
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Abstract

We discuss finite temperature quantum Monte Carlo methods in the framework of the interacting nuclear shell model. The methods are based on a representation of the imaginary-time many-body propagator as a superposition of one-body propagators describing non-interacting fermions moving in fluctuating auxiliary fields. Fermionic Monte Carlo calculations have been limited by a ``sign'' problem. A practical solution in the nuclear case enables realistic calculations in much larger configuration spaces than can be solved by conventional methods. Good-sign interactions can be constructed for realistic estimates of certain nuclear properties. We present various applications of the methods for calculating collective properties and level densities.

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Y. Alhassid. 2000-09-05. Quantum Monte Carlo Methods for Nuclei at Finite Temperature. https://doi.org/10.1142/s0217979201005945

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