We investigate the fermions of the standard model without a Higgs scalar. Instead, we consider a nonlocal four-quark interaction in the tensor channel which is characterized by a single dimensionless coupling $f$. Quantization leads to a consistent perturbative expansion for small $f$. The running of $f$ is asymptotically free and therefore induces a nonperturbative scale ${\Lambda }_{\mathrm{ch}}$, in analogy to the strong interactions. We argue that spontaneous electroweak symmetry breaking is triggered at a scale where $f$ grows large and find the top quark mass of the order of ${\Lambda }_{\mathrm{ch}}$. We also present a first estimate of the effective Yukawa coupling of a composite Higgs scalar to the top quark, as well as the associated mass ratio between the top quark and the $W$ boson.

• Received 20 January 2010

DOI:https://doi.org/10.1103/PhysRevD.81.055005