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arXiv · hep-th/9412093

Complex-time path-integral formalism for quantum tunneling

Hideaki Aoyama·Toshiyuki Harano
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Abstract

The complex-time formalism is developed in the framework of the path-integral formalism, to be used for analysis of the quantum tunneling phenomena. We show that subleading complex-time saddle-points do not account for the right WKB result. Instead, we develop a reduction formula, which enables us to construct Green functions from simple components of the potential, for which saddle-point method is applicable. This method leads us to the valid WKB result, which incorporates imaginary-time instantons and bounces, as well as the real-time boundary conditions.

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Hideaki Aoyama, Toshiyuki Harano. 1994-12-12. Complex-time path-integral formalism for quantum tunneling. https://doi.org/10.1016/0550-3213(95)00163-m

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