2012/07/31 by Martin B. Einhorn, Martin B Einhorn, D. R. Timothy Jones +1 · 34 citations
Earth and Planetary Sciences · Physics and Astronomy · #Cosmology and Gravitation Theories #Coupling (piping) #Earth Systems and Cosmic Evolution #Gauge (firearms) #Higgs boson #Higgs field #Inflation (cosmology) #Invariant (physics) #Particle physics theoretical and experimental studies #Planck #Planck scale #Scalar (mathematics) #Scale invariance #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1088/1475-7516/2012/11/049
published in Journal of Cosmology and Astroparticle Physics 2012(11), 049 (Institute of Physics) · 32 pages, no figures; minor corrections, improved discussion and added references
arxiv created 2012/09/14 · openalex publication_date 2012/11/23 · arxiv updated 2015/06/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Motivated by the idea that there is new physics beyond the Standard Model (SM), we have investigated a number of models for Grand Unified Theories (GUTS) in four dimensions for the possibility that their Higgs fields might be responsible for inflation in the early universe. In addition to models having an intrinsic Planck mass parameter, we have entertained classically scale invariant models in which the Planck scale itself as well as the GUT scale is induced by spontaneous breaking of the gauge symmetry. We found that in non-supersymmetric SU(5) with the usual Higgs in the adjoint representation but with large non-minimal coupling to the curvature, there appear to be several possible flat directions that might lead to inflation. Interestingly, the one of lowest energy is the breaking into SU(3)⊗SU(2)⊗U(1) that is suggested by gauge coupling unification. Further, we show that this flat direction is stable against small fluctuations in other directions. We attempted to extend this to similar supersymmetric GUTS, both global and supergravity, but did not succeed in finding a phenomenologically acceptable model of this type, with a “minimal” Kähler potential augmented only by terms characterised by dimensionless coupling constants. As is often the case, such models suffered either from a negative vacuum energy or from tachyonic modes. We also considered a variant of an “inverted hierarchy” model in which the GUT scale is set by dimensional transmutation, but were unable to find a phenomenologically acceptable model.