Renormalization of the θ angle, the quantum Hall effect and the strong CP problem
Abstract
We discuss the need for and consequences of non-perturbative renormalizations of couplings including the vacuum θ angle. An explicit example of these effects is found in the recently proposed scaling theory of the integral quantum Hall effect. In that theory the θ angle has a precise parallel in the value of the Hall conductivity σxy which flows from its CPA (short distance) value to quantization at macroscopic distances. We further comment that such θ scaling phenomena provide a mechanism for strong CP conservation.
- Publication:
-
Physics Letters B
- Pub Date:
- January 1985
- DOI:
- 10.1016/0370-2693(85)90165-0
- Bibcode:
- 1985PhLB..150..182L