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Coarse graining and renormalization

Ji-Feng Yang
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Abstract

Formulating the QFT's as coarse grained 'low' energy sectors of a postulated complete quantum theory of everything with the 'high' energy modes integrated out or 'clustering' into 'low' energy objects, we can evaluate the Feynman amplitudes by solving a series of natural differential equations which automatically dissolves the necessity of infinity subtraction and the associated subtleties. This new strategy has direct implications to the scheme dependence problem.

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Ji-Feng Yang. 2001-11-24. Coarse graining and renormalization. https://arxiv.org/abs/hep-th/0008037

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