Intermediate Symmetries in the Spontaneous Breaking of Supersymmetric SO(10)
Abstract
We study the supersymmetric spontaneous symmetry breaking of SO(10) into SU(3) ⊗ SU(2) ⊗ U(1) for the most physically interesting cases of SU(5) or flipped SU(5) ⊗ U(1) intermediate symmetries. The first case is more easily realized while the second one requires a finetuning condition on the parameters of the superpotential. This is because in the case of SU(5) symmetry there is at most one singlet of the residual symmetry in each SO(10) irreducible representation. We also point out on more general grounds in supersymmetric GUTs that some intermediate symmetries can be exactly realized and others can only be approximated by finetuning. In the first category, there could occur some tunneling between the vacua with exact and approximate intermediate symmetry. The flipped SU(5) ⊗ U(1) symmetry improves the unification of gauge couplings if (BL) is broken by ∥(BL)∥ =1 scalars yielding righthanded neutrino masses below 10^{14} GeV.
 Publication:

Modern Physics Letters A
 Pub Date:
 2002
 DOI:
 10.1142/S0217732302007429
 arXiv:
 arXiv:hepph/0202278
 Bibcode:
 2002MPLA...17.1239B
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 LaTex, 9 pages