Why the Standard Model? Some Answers and Predictions

by Ali Chamseddine (American University of Beirut)

Thursday 20 Sept 2007, 14:00 → 15:00 Europe/Zurich

TH Theory Conference Room (CERN)

We assume that space-time is the product of a continuous four-dimensional manifold times a finite non-commutative space F. We classify the irreducible representations of F consistent with imposing reality and chiral conditions on spinors, to avoid the fermion doubling problem. The spectral action is the pure gravitational action of the non-commutative space. It gives, almost uniquely, the Standard Model with all its details, predicting the number of fermions per generation to be 16, their representations and the Higgs breaking mechanism, with very little input. The geometrical model is valid at the unification scale, and have relations connecting the gauge couplings to each other and to the Higgs coupling. This allows for a prediction of the Higgs mass of around 170 GeV. There is also a mass relation connecting the sum of the square of the masses of the fermions to the W mass square, which enables us to predict the top quark mass be compatible with the measured experimental value. We thus manage to have the advantages of both SO(10) and Kaluza-Klein unification, without paying the price of plethora of Higgs fields or the tower of infinite states. Additional supporting evidence will also be presented.