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arXiv · 0804.4091

Causal signal transmission by quantum fields. II. Quantum-statistical response of interacting bosons

L. I. Plimak·S. Stenholm
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Abstract

We analyse nonperturbatively signal transmission patterns in Green's functions of interacting quantum fields. Quantum field theory is re-formulated in terms of the nonlinear quantum-statistical response of the field. This formulation applies equally to interacting relativistic fields and nonrelativistic models. Of crucial importance is that all causality properties to be expected of a response formulation indeed hold. Being by construction equivalent to Schwinger's closed-time-loop formalism, this formulation is also shown to be related naturally to both Kubo's linear response and Glauber's macroscopic photodetection theories, being a unification of the two with generalisation to the nonlinear quantum-statistical response problem. In this paper we introduce response formulation of bosons; response reformulation of fermions will be subject of a separate paper.

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L. I. Plimak, S. Stenholm. 2008-04-25. Causal signal transmission by quantum fields. II. Quantum-statistical response of interacting bosons. https://doi.org/10.1016/j.aop.2007.11.014

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