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Improving the Renormalization Group approach to the quantum-mechanical double well potential

D. Zappala'
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Abstract

The gap between ground and first excited state of the quantum-mechanical double well is calculated using the Renormalization Group equations to the second order in the derivative expansion, obtained within a class of proper time regulators. Agreement with the exact results is obtained both in the strong and weak coupling regime.

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D. Zappala'. 2001-08-05. Improving the Renormalization Group approach to the quantum-mechanical double well potential. https://doi.org/10.1016/s0375-9601(01)00642-9

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