Non-Gaussianities in DBI inflation with angular motion

Taichi Kidani, Kazuya Koyama
2014 Physical Review D  
We study DBI spinflation models with angular potentials that are derived in string theory. We analyse the background dynamics with different parameter sets and study the impact of changing each parameter on inflationary dynamics. It is known that the conversion of the entropy perturbation into the curvature perturbation gives multi-field DBI inflation models a possibility of satisfying the observational constraints by relaxing the stringent microphysical constraint that disfavours single field
more » ... vours single field DBI inflation models. we show that our model is excluded by the Planck satellite observations even with the conversion mechanism regardless of the parameter set.
doi:10.1103/physrevd.90.023515 fatcat:khhil7q7brcxvgptdrk6entzii