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arXiv · hep-th/9510046

BRST invariant approach to quantum mechanical tunneling

Jian-Ge Zhou·F. Zimmerschied·J. -Q. Liang·H. J. W. Mueller-Kirsten
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Abstract

A new approach with BRST invariance is suggested to cure the degeneracy problem of ill defined path integrals in the path-integral calculationof quantum mechanical tunneling effects in which the problem arises due to the occurrence of zero modes. The Faddeev-Popov procedure is avoided and the integral over the zero mode is transformed in a systematic way into a well defined integral over instanton positions. No special procedure has to be adopted as in the Faddeev-Popov method in calculating the Jacobian of the transformation. The quantum mechanical tunneling for the Sine-Gordon potential is used as a test of the method and the width of the lowest energy band is obtained in exact agreement with that of WKB calculations.

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Jian-Ge Zhou, F. Zimmerschied, J. -Q. Liang, H. J. W. Mueller-Kirsten. 1995-10-09. BRST invariant approach to quantum mechanical tunneling. https://doi.org/10.1016/0370-2693(95)01268-0

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