We continue the study, initiated in [L. Fei, S. Giombi, and I.R. Klebanov, Phys. Rev. D 90, 025018 (2014)], of the O(N) symmetric theory of N+1 massless scalar fields in 6-ε dimensions. This theory has cubic interaction terms 12g1σ(φi)2+16g2σ3. We calculate the three loop beta functions for the two couplings and use them to determine certain operator scaling dimensions at the IR stable fixed point up to order ε3. We also use the beta functions to determine the corrections to the critical value of N below which there is no fixed point at real couplings. The result suggests a significant reduction in the critical value as the dimension is decreased to 5. We also study the theory with N=1, which has a Z2 symmetry under φ→-φ. We show that it possesses an IR stable fixed point at imaginary couplings which can be reached by flow from a nearby fixed point describing a pair of N=0 theories. We calculate certain operator scaling dimensions at the IR fixed point of the N=1 theory and suggest that, upon continuation to two dimensions, it describes a nonunitary conformal minimal model.
|Physical Review D - Particles, Fields, Gravitation and Cosmology
|Published - Feb 10 2015
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)