Running coupling in electroweak interactions of leptons from   f(R)-gravity with torsion
  The f(R)-gravitational theory with torsion is considered for one family of leptons; it is found that the torsion tensor gives rise to interactions having the structure of the weak forces while the intrinsic non-linearity of the f(R) function provides an energy-dependent coupling: in this way, torsional f(R) gravity naturally generates both structure and strength of the electroweak interactions among leptons. This implies that the weak interactions among the lepton fields could be addressed as a geometric effect due to the interactions among spinors induced by the presence of torsion in the most general f(R) gravity. Phenomenological considerations are addressed. 
Salvatore Capozziello, Mariafelicia De Laurentis, Luca Fabbri, Stefano   Vignolo
gr-qc astro-ph.EP hep-th