Fermions and Goldstone bosons in an asymptotically safe model
May, 2011
Citations per year
Abstract: (Elsevier)
We consider a model in which Goldstone bosons, described by a SU(N) chiral nonlinear σ model, are coupled to an N -plet of colored fermions by means of a Yukawa interaction. We study the one-loop renormalization group flow and show that the non-Gaussian UV fixed point, which is present in the purely bosonic model, is lost because of fermion loop effects unless N is sufficiently large. We then add four-fermion contact interactions to the Lagrangian and show that in this case there exist several non-Gaussian fixed points. The strength of the contact interactions, predicted by the requirement that the theory flows towards a fixed point in the UV, is compared to the current experimental bounds. This toy model could provide an important building block of an asymptotically safe model of the weak interactions.Note:
- 7 pages, 3 figures, 1 table
- 11.15.Ex
- 12.39.Fe
- 11.10.Hi
- 12.60.Fr
- fixed point: non-Gaussianity
- weak interaction: model
- renormalization group: flow
- sigma model: nonlinear
- interaction: Yukawa
- contact interaction
References(16)
Figures(4)