A unified sedenion model for the origins of three generations of charged and neutral leptons, flavor mixing, mass oscillations and small masses of neutrinos

We present a unified model without the need for an ad hoc Standard Model hypothesis; we explain why there are three generations of charged and neutral leptons, why neutrinos have a vanishingly small mass, and why flavor-mixing emerges and mass oscillations occur. We show that the sedenion algebra contains three types of non-associative octonion algebra, with each corresponding to a generation of leptons. By incorporating extra degrees of freedom, the generalized higher dimensional Dirac equation accounts for the internal structural dynamics. This study sheds light on the intrinsic physical properties of three generations of charged leptons and neutrinos and their distinctive spacetime structures.