Finite Temperature Effect on Wilson Loop Mechanism
  We evaluate the energy splitting of vacua appearing in the gauge theory in the space $M_4\times S^N/Z_2$ ($N=2,3,4,5,6$ and $7$). One-loop quantum effects which come from scalar and gauge fields are considered. We calculate them at zero temperature as well as in high-temperature limit. We find that in these situations there is no breakdown of the gauge symmetry. 
Kiyoshi Shiraishi
hep-th