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arXiv · 1108.4474

Scale dependences of local form non-Gaussianity parameters from a DBI isocurvature field

Qing-Guo Huang·Chunshan Lin
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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.

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Qing-Guo Huang, Chunshan Lin. 2011-08-23. Scale dependences of local form non-Gaussianity parameters from a DBI isocurvature field. https://doi.org/10.1088/1475-7516/2011/10/005

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