The standard model, the Pati-Salam model, and "Jordan geometry"

Abstract

We argue that the ordinary commutative-and-associative algebra of spacetime coordinates (familiar from general relativity) should perhaps be replaced, not by a noncommutative algebra (as in noncommutative geometry), but rather by a Jordan algebra (leading to a framework which we term "Jordan geometry"). We present the Jordan algebra (and representation) that most nearly describes the standard model of particle physics, and we explain that it actually describes a certain (phenomenologically viable) extension of the standard model: by three right-handed (sterile) neutrinos, a complex scalar field $\phi$, and a $U(1{)}_{B-L}$ gauge boson which is Higgsed by $\phi$. We then note a natural extension of this construction, which describes the $SU(4)\times SU(2{)}_L\times SU(2{)}_R$ Pati-Salam model. Finally, we discuss a simple and natural Jordan generalization of the exterior algebra of differential forms.

Comments: v1: 16 pages; v2: references added v3: minor revisions, references added