The Casimir Force for a Perfectly Conducting Rectangular Parallelepiped at Finite Temperature

Abstract

Quantized electromagnetic field inside a rectangular parallelepiped surrounded by perfectly conducting parallel walls is studied. The Casimir energy and the Casimir force at finite temperature are calculated by the mode summation method, and it is found that the sign of the Casimir force depend on both the shape of a cavity and the temperature. The temperature at which the Casimir force change from the attractive force to the repulsive force is shown as a function of the separation of walls. The correction of the Casimir force between perfectly conducting plates for the finite size effect is also considered.