2019/01/31 by Tommi Tenkanen
Mathematics · Physics and Astronomy · #Algorithm #Black Holes and Theoretical Physics #Computer science #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Geometry #Higgs boson #Inflation (cosmology) #Inflaton #Mathematical physics #Mathematics #Particle physics #Physics #Quantum mechanics #Scalar (mathematics) #Spectral index #Spectral line #Theoretical physics #astro-ph.CO #gr-qc #hep-ph
paper · pdf · doi:10.1103/physrevd.99.063528
published as Phys. Rev. D 99, 063528 (2019) · 6 pages, 1 figure, 1 table. v2: Important modifications, results partly changed. v3: Minor modifications, matches the version accepted for publication in Phys. Rev. D
openalex created_date 2019/01/11 · arxiv created 2019/03/19 · openalex publication_date 2019/03/26 · arxiv updated 2019/04/03 · openalex updated_date 2026/08/05
It has recently been suggested that the Standard Model Higgs boson could act as the inflaton while minimally coupled to gravity---given that the gravity sector is extended with an \ensuremathαR2 term and the underlying theory of gravity is of Palatini, rather than metric, type. In this paper, we revisit the idea and correct some shortcomings in earlier studies. We find that, in this setup, the Higgs can indeed act as the inflaton and that the tree-level predictions of the model for the spectral index and the tensor-to-scalar ratio are ns\ensuremath≃0.941, r\ensuremath≃0.3/(1+10^\ensuremath-8\ensuremathα), respectively, for a typical number of e-folds, N=50, between horizon exit of the pivot scale k=0.05 Mpc^\ensuremath-1 and the end of inflation. Even though the tensor-to-scalar ratio is suppressed compared to the usual minimally coupled case and can be made compatible with data for large enough \ensuremathα, the result for ns is in severe tension with the Planck results. We briefly discuss extensions of the model.