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arXiv · hep-th/9805015

A proof of the irreversibility of renormalization group flows in four dimensions

Stefano Forte·Jose I. Latorre
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Abstract

We present a proof of the irreversibility of renormalization group flows, i.e. the c-theorem for unitary, renormalizable theories in four (or generally even) dimensions. Using Ward identities for scale transformations and spectral representation arguments, we show that the c-function based on the trace of the energy-momentum tensor (originally suggested by Cardy) decreases monotonically along renormalization group trajectories. At fixed points this c-function is stationary and coincides with the coefficient of the Euler density in the trace anomaly, while away from fixed points its decrease is due to the decoupling of positive--norm massive modes.

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Stefano Forte, Jose I. Latorre. 1998-09-18. A proof of the irreversibility of renormalization group flows in four dimensions. https://doi.org/10.1016/s0550-3213(98)00631-2

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