Are there scaling solutions in the O(N)-models for large N in d>4?
arXiv:1405.6622 · doi:10.1103/PhysRevD.90.107702
Abstract
There have been some speculations about the existence of critical unitary O(N)-invariant scalar field theories in dimensions 4<d<6 and for large N. Using the functional renormalization group equation, we show that in the lowest order of the derivative expansion, and assuming that the anomalous dimension vanishes for large , the corresponding critical potentials are either unbounded from below or singular for some finite value of the field.
5 pages, 4 figures, expanded introduction, in press on PRD