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Mass Renormalization for Time Dependent Correlation Functions in Shibata-Hashitsume's Projection Operator Method

T. Koide·M. Maruyama·F. Takagi
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Abstract

We study the time development of correlation functions at both zero and finite temperature with Shibata-Hashitsume's projection operator method and carry out the renormalization of ultraviolet divergence that appears in a time-dependent frequency shift, using a mass counter term. A harmless divergence of log t-type remains at an initial time t=0 after the lowest order renormalization.

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T. Koide, M. Maruyama, F. Takagi. 1998-03-09. Mass Renormalization for Time Dependent Correlation Functions in Shibata-Hashitsume's Projection Operator Method. https://arxiv.org/abs/hep-th/9803070

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