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arXiv · hep-th/0207261

Sine-Gordon Effective Potential beyond Gaussian Approximation

Wen-Fa Lu·Chul Koo Kim·Kyun Nahm
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Abstract

Combining an optimized expansion scheme in the spirit of the background field method with the Coleman's normal-ordering renormalization prescription, we calculate the effective potential of sine-Gordon field theory beyond the Gaussian approximation. The first-order result is just the sine-Gordon Gaussian effective potential (GEP). For the range of the coupling beta^2 <= 3.4 pi (an approximate value), a calculation with Mathematica indicates that the result up to the second order is finite without any further renormalization procedure and tends to improve the GEP more substantially while beta^2 increases from zero.

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Wen-Fa Lu, Chul Koo Kim, Kyun Nahm. 2002-08-14. Sine-Gordon Effective Potential beyond Gaussian Approximation. https://doi.org/10.1016/s0370-2693(02)02659-x

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