Jun Nishimura, Asato Tsuchiya
Recently we have shown that (3+1)-dimensional expanding universe appears dynamically and uniquely from the type IIB matrix model, which is a nonperturbative formulation of superstring theory. Here we propose a concrete procedure to identify the local fields corresponding to the massless modes that appear at late times in the same formulation. The spontaneous breaking of (9+1)-dimensional Poincare symmetry and supersymmetry plays a crucial role. We find that the effective field theory below the Planck scale is given generically by a SU(k) grand unified theory with (i) four generations of Weyl fermion with vector-like partners and (ii) 21 scalar bosons, both in the adjoint representation of SU(k). We speculate on how the Standard Model emerges at low energy and how the hierarchy problem is solved in this top-down approach.
View original:
http://arxiv.org/abs/1208.4910
No comments:
Post a Comment