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تسجيل مستخدم جديدTransformations of real-time finite-temperature Feynman rules
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We consider transformations of the $2times2$ propagator matrix in real-time finite-temperature field theory, resulting in transformed $n$--point functions. As special cases of such a transformation we examine the Keldysh basis, the retarded/advanced $RA$ basis, and a Feynman-like $Fbar F$ basis, which differ in this context as to how ``economically certain constraints on the original propagator matrix elements are implemented. We also obtain the relation between some of these real-time functions and certain analytic continuations of the imaginary-time functions. Finally, we compare some aspects of these bases which arise in practical calculations.
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