Statistical difference at high temperature in particle creation

摘要

The creation of particles is a natural consequence of quantum field theory in curved space-time. We study this phenomenon at finite temperature by using Thermo Field Dynamics (TFD). In the conventional TFD formulated in the thermal Schr?dinger picture, temperature is included in the state vectors. We adopt another approach where the temperature is absorbed in operators, so that the double (time and thermal) Bogoliubov transformations of the operators in curved space-time can be unified consistently with TFD, giving a correct number of particles created from false vacuum at finite temperature. We found that the net number of particles created at time t due to thermal effects and curved space-time is given by , where is the number of particles at time t and the initial distribution for bosons (σ = 1) and fermions (σ = - 1) at temperature T(= 1/k Bβ), respectively. Thermal state condition in THP is also given in a general form.