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Non-Perturbative Renormalization Group and Quantum Tunnelling

Ken-Ichi Aoki·Atsushi Horikoshi·Masaki Taniguchi·Haruhiko Terao
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Abstract

The non-perturbative renormalization group (NPRG) is applied to analysis of tunnelling in quantum mechanics. The vacuum energy and the energy gap of anharmonic oscillators are evaluated by solving the local potential approximated Wegner-Houghton equation (LPA W-H eqn.). We find that our results are very good in a strong coupling region, but not in a very weak coupling region, where the dilute gas instanton calculation works very well. So it seems that in analysis of quantum tunnelling, the dilute gas instanton and LPA W-H eqn. play complementary roles to each other. We also analyze the supersymmetric quantum mechanics and see if the dynamical supersymmetry (SUSY) breaking is described by NPRG method.

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Ken-Ichi Aoki, Atsushi Horikoshi, Masaki Taniguchi, Haruhiko Terao. 1998-12-06. Non-Perturbative Renormalization Group and Quantum Tunnelling. https://arxiv.org/abs/hep-th/9812050

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