Comment on Fermionic and Bosonic Pair-creation in an External Electric Field at Finite Temperature

摘要

We show that contrary to the claim made by Hallin and Liljenberg in Phys.Rev. D52 1150,(1995), (hep-th/9412188) the thermal correction to the thermaldecay or pair production rate for a system placed in a heat bath in thepresence of an external electric field, is always nonzero in the finite as wellas infinite time limit. Using the formalism outlined there, we reestimate thedecay rate for different values of temperature, mass and time.We also try toidentify the parameter ranges where the quantity of interest agrees with thatcomputed previously, at high temperature (in the infinite time limit), from theimaginary part of the effective action using imaginary time and real timeformalism of thermal field theory. We also point out that in the strictlyinfinite time limit, the correct decay rate as obtained from the work of Hallinet. al. tends to diverge.