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Liouville-Neumann Approach to the Nonperturbative Quantum Field Theory

Sang Pyo Kim
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Abstract

We present a nonperturbative field theoretic method based on the Liouville-Neumann (LN) equation. The LN approach provides a unified formulation of nonperturbative quantum fields and also nonequilibrium quantum fields, which makes use of mean-field type equations and whose results at the lowest level are identically the same as those of the Gaussian effective potential approach and the mean-field approach. The great advantageous point of this formulation is its readiness of applicability to time-dependent quantum systems and to finite temperature field theory, and its possibility to go beyond the Gaussian approximation.

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Sang Pyo Kim. 1997-07-15. Liouville-Neumann Approach to the Nonperturbative Quantum Field Theory. https://arxiv.org/abs/hep-th/9706052

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