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arXiv · 1008.1867

Dynamic coarse-graining approach to quantum field theory

Hans Christian Öttinger
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Abstract

We build quantum field theory on the thermodynamic master equation for dissipative quantum systems. The vacuum is represented by a thermodynamic equilibrium state in the low-temperature limit. All regularization is consistently provided by a friction mechanism; with decreasing friction parameter, only degrees of freedom on shorter and shorter length scales are damped out of a quantum field theory. No divergent integrals need to be manipulated. Renormalization occurs as a tool to refine perturbation expansions, not to remove divergences. Relativistic covariance is recovered in the final results. We illustrate the proposed thermodynamic approach to quantum fields for the phi^4 theory by calculating the propagator and the beta function, and we offer some suggestions on its application to gauge theories.

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Hans Christian Öttinger. 2010-08-11. Dynamic coarse-graining approach to quantum field theory. https://doi.org/10.1103/physrevd.84.065007

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