Barton expansion and the path integral approach in thermal field theory.
نویسندگان
چکیده
It has been shown how on-shell forward scattering amplitudes (the “Barton expansion”) and quantum mechanical path integral (QMPI) can both be used to compute temperature dependent effects in thermal field theory. We demonstrate the equivalence of these two approaches and then apply the QMPI to compute the high temperature expansion for the fourpoint function in QED, obtaining results consistent with those previously obtained from the Barton expansion. 11.10.Wx
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عنوان ژورنال:
- Physical review. D, Particles and fields
دوره 54 10 شماره
صفحات -
تاریخ انتشار 1996