https://doi.org/10.1140/epjc/s10052-008-0808-y
Regular Article - Theoretical Physics
Standard model and gravity from spinors
University of L’Aquila & INFN–LNGS, 67100, L’Aquila, Italy
* e-mail: nesti@aquila.infn.it
Received:
30
September
2008
Revised:
5
November
2008
Published online:
26
November
2008
It is shown how the Lorentz and standard-model gauge groups can be unified by using algebraic spinors of the standard four-dimensional Clifford algebra, in left–right symmetric fashion. This defines a framework of unification with gravity and generates exactly a standard-model family of fermions, while a Pati–Salam unification group emerges, at the Planck scale, where (chiral) gravity decouples. We show that this low-energy broken phase emerges from the VEV of extended vierbein fields, which at this stage are assumed to be dynamically generated from a theory in the fully symmetric phase valid beyond the Planck scale (and whose consistency and dynamics is thus yet to be assessed) providing thus a geometrical and group-theoretical framework for the unification and breaking. At low energy, on the other hand, it is intriguing to find, as a remnant of this unification, new isospin-triplet spin-two particles that may naturally lie at the weak scale, providing a striking signal at the LHC.
PACS: 04.50.+h –
© Springer-Verlag , 2009