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Quantum-field-theoretical techniques for stochastic representation of quantum problems

L. I. Plimak·M. Fleischhauer·M. K. Olsen·M. J. Collett
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Abstract

We describe quantum-field-theoretical (QFT) techniques for mapping quantum problems onto c-number stochastic problems. This approach yields results which are identical to phase-space techniques [C.W. Gardiner, {\em Quantum Noise} (1991)] when the latter result in a Fokker-Planck equation for a corresponding pseudo-probability distribution. If phase-space techniques do not result in a Fokker-Planck equation and hence fail to produce a stochastic representation, the QFT techniques nevertheless yield stochastic difference equations in discretised time.

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L. I. Plimak, M. Fleischhauer, M. K. Olsen, M. J. Collett. 2001-02-27. Quantum-field-theoretical techniques for stochastic representation of quantum problems. https://arxiv.org/abs/cond-mat/0102483

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