Speaker
Takao Suyama
(KEK)
Description
In SU(N) gauge theory, it is argued recently that there exists a "mixed
anomaly" between the CP symmetry and the 1-form ZN symmetry at \theta=\
pi, and the anomaly matching requires CP to be spontaneously broken at \
theta=\pi if the system is in the confining phase. In this talk, we
elaborate on this discussion by examining the large volume behavior of
the partition functions of the SU(N)/Z_N theory on T^4 a la 't Hooft.
The periodicity of the partition function in \theta, which is not 2\pi
due to fractional instanton numbers, suggests the presence of a phase
transition at \theta=\pi.
Author
Takao Suyama
(KEK)
