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Order parameter evolution in scalar QFT: renormalization group resummation of secular terms

H. J. de Vega·J. F. J. Salgado
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Abstract

The quantum evolution equations for the field expectation value are analytically solved to cubic order in the field amplitude and to one-loop level in the lambda phi-fourth model. We adapt and use the renormalization group (RG) method for such non-linear and non-local equations. The time dependence of the field expectation value is explicitly derived integrating the RG equations. It is shown that the field amplitude for late times approaches a finite limit as the time to the power -3/2. This limiting value is expressed as a function of the initial field amplitude.

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H. J. de Vega, J. F. J. Salgado. 1997-01-21. Order parameter evolution in scalar QFT: renormalization group resummation of secular terms. https://doi.org/10.1103/physrevd.56.6524

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