Renormalization group flow of $O(N)^3$-invariant general sextic tensor model

Abstract

We compute the beta functions for the $O(N)^3$-invariant general sextic tensor model up to cubic order in the coupling constant, and at leading order in the $1/N$ expansion. Our method is a direct, explicit one, in the sense that we identify the appropriate Feynman graphs, we compute their amplitudes which then allows us to obtain the $β$ functions of the model. We perform these computation considering both a long-range and a short-range propagator, within the dimensional regularization framework. We find three fixed points in the short-range case and a line of fixed points, parameterized by the wheel interaction, in the long-range case. This line of fixed points is identical to the one found in the case of the $U(N)^3$-invariant model. Our result proves that the additional $O(N)^3$-invariant interactions do not modify the long-range fixed point structure of the model.

Figures (12)

• Figure 1: The $O(N)^3$-invariant sextic interactions. Color permutations are implicit.
• Figure 2: A triple-tadpole graph displayed in the stranded (left), bubble (center), and Feynman (right) representations.
• Figure 3: Dominant $2-$point graphs up to cubic order in $\lambda$.
• Figure 4: Leading order $6-$point graphs up to cubic order in $\lambda$.
• Figure 5: Dominant $6-$point melon graph with $I_5$ external index structure.