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arXiv · 1105.1826

Renormalization: the observable-state model

Juan Sebastián Ardenghi·Mario Castagnino
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Abstract

The usual mathematical formalism of quantum field theory is non-rigorous because it contains divergences that can only be renormalized by non-rigorous mathematical methods. The purpose of this paper is to present a method of subtraction of this divergences using the formalism of decoherence. This is achieved by replacing the standard renormalization method by a projector on a well defined Hilbert subspace. In this way a list of problems of the standard formalism disappears while the physical results of QFT remains valid. From it own nature, this formalism can be used in non-renormalizable theories.

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Juan Sebastián Ardenghi, Mario Castagnino. 2011-12-06. Renormalization: the observable-state model. https://doi.org/10.1103/physrevd.85.025002

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