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arXiv · hep-ph/9803235

When to carry out analytic continuation?

Jian Zuo Yuan-Xing Gui
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Abstract

This paper discusses the analytic continuation in the thermal field theory by using the theory of $η-ξ$ spacetime. Taking a simple model as example, the $2\times 2$ matrix real-time propagator is solved from the equation obtained through continuation of the equation for the imaginary-time propagator. The geometry of the $η-ξ$ spacetime plays important role in the discussion.

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Jian Zuo Yuan-Xing Gui. 1998-03-04. When to carry out analytic continuation?. https://arxiv.org/abs/hep-ph/9803235

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