delta T/T and neutrino masses in SU(5)

摘要

We implement inflation in a supersymmetric SU(5) model with U(I) R-symmetry such that the cosmic microwave anisotropy deltaT/T is proportional to (M/M-Planck)2, where M similar to M-GUT = 2-3 x 10(16) GeV, the SU(5) breaking scale, and M-Planck = 2.4 x 10(19) GeV. The presence of a global U(I)X symmetry, spontaneously broken also at scale M-GUT, provides an upper bound M-GUT(2)/M-Planck similar to10(14) GeV on the masses of SU(5) singlet right-handed neutrinos, which explains the mass scale associated with atmospheric neutrino oscillations. The SU(5) monopoles and U(I)(X) cosmic strings are inflated away. Although the doublet-triplet splitting requires fine-tuning, the MSSM mu problem is resolved and dimension five proton decay is strongly suppressed. (C) 2004 Elsevier B.V. All rights reserved.