Chiral symmetry breaking in nearly conformal gauge theories

Understand

We present new results on chiral symmetry breaking in nearly conformal gauge theories with fermions in the fundamental representation of the SU(3) color gauge group.

• The number of fermion flavors is varied in an extended range below the conformal window with chiral symmetry breaking ($\chi{\rm SB}$) for all flavors between $N_f=4$ and $N_f=12$.
• To identify $\chi{\rm SB}$ we apply several methods which include, within the framework of chiral perturbation theory, the analysis of the Goldstone spectrum in the p-regime and the spectrum of the fermion Dirac operator with eigenvalue distributions of random matrix theory in the $\eps$-regime.
• Chiral condensate enhancement is observed with increasing $N_f$ when the electroweak symmetry breaking scale $F$ is held fixed in technicolor language.