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arXiv · hep-th/9402117

A Renormalization Group Flow Approach to Decoupling and Irrelevant Operators

Chanju Kim
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Abstract

Using Wilson-Polchinski renormalization group equations, we give a simple new proof of decoupling in a $ϕ^4$-type scalar field theory involving two real scalar fields (one is heavy with mass $M$ and the other light). Then, to all orders in perturbation theory, it is shown that effects of virtual heavy particles up to the order $1/M^{2N_0}$ can be systematically incorporated into light-particle theory via effective local vertices of canonical dimension at most $4+2N_0$. The couplings for vertices of dimension $4+2N$ are of order $1/M^{2N}$ and are systematically calculable. All this is achieved through intuitive dimensional arguments without resorting to complicated graphical arguments or convergence theorems.

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Chanju Kim. 1995-03-21. A Renormalization Group Flow Approach to Decoupling and Irrelevant Operators. https://doi.org/10.1006/aphy.1995.1093

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