Multifield dynamics in Higgsotic inflation
Abstract
In Higgsotic inflation a complex neutral scalar combination of the h ^{0} and H ^{0} MSSM Higgs fields plays the role of inflaton in a chaotic fashion. The potential is protected from large transPlanckian corrections at large inflaton if the system is embedded in string theory so that the Higgs fields parametrize a Dbrane position. The inflaton potential is then given by a DBI+CS Dbrane action yielding an approximate linear behaviour at large field. The inflaton scalar potential is a 2field model with specific noncanonical kinetic terms. Previous computations of the cosmological parameters (i.e. scalar and tensor perturbations) did not take into account the full 2field character of the model, ignoring in particular the presence of isocurvature perturbations and their coupling to the adiabatic modes. It is well known that for generic 2field potentials such effects may significantly alter the observational signatures of a given model. We perform a full analysis of adiabatic and isocurvature perturbations in the Higgsotic 2field model. We show that the predictivity of the model is increased compared to the adiabatic approximation. Isocurvature perturbations moderately feed back into adiabatic fluctuations. However, the isocurvature component is exponentially damped by the end of inflation. The tensor to scalar ratio varies in a region r = 0 .080 .12, consistent with combined Planck/BICEP results.
 Publication:

Journal of High Energy Physics
 Pub Date:
 January 2016
 DOI:
 10.1007/JHEP01(2016)128
 arXiv:
 arXiv:1505.00221
 Bibcode:
 2016JHEP...01..128B
 Keywords:

 Cosmology of Theories beyond the SM;
 Flux compactifications;
 Compactification and String Models;
 Dbranes;
 High Energy Physics  Theory;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Phenomenology
 EPrint:
 35 pages, 11 figures