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Quantum number projection at finite temperature via thermofield dynamics

K. Tanabe·H. Nakada
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Abstract

Applying the thermo field dynamics, we reformulate exact quantum number projection in the finite-temperature Hartree-Fock-Bogoliubov theory. Explicit formulae are derived for the simultaneous projection of particle number and angular momentum, in parallel to the zero-temperature case. We also propose a practical method for the variation-after-projection calculation, by approximating entropy without conflict with the Peierls inequality. The quantum number projection in the finite-temperature mean-field theory will be useful to study effects of quantum fluctuations associated with the conservation laws on thermal properties of nuclei.

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K. Tanabe, H. Nakada. 2005-01-12. Quantum number projection at finite temperature via thermofield dynamics. https://doi.org/10.1103/physrevc.71.024314

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