Scale dependences of local form non-Gaussianity parameters from a DBI isocurvature field
arXiv:1108.4474 · doi:10.1088/1475-7516/2011/10/005
Abstract
We derive the spectral indices and their runnings of local form $f_{NL}$ and $g_{NL}$ from a DBI isocurvature field and we find that the indices are suppressed by the sound speed $c_s$. This effect can be interpreted by the Lorentz boost from the viewpoint in the frame where brane is moving.
12 pages, 1 figure