Primordial non-Gaussianity in the bispectra of large-scale structure

Understand

The statistics of large-scale structure in the Universe can be used to probe non-Gaussianity of the primordial density field, complementary to existing constraints from the cosmic microwave background.

• In particular, the scale dependence of halo bias, which affects the halo distribution at large scales, represents a promising tool for analyzing primordial non-Gaussianity of local form.
• Future observations, for example, may be able to constrain the trispectrum parameter gNL that is difficult to study and constrain using the CMB alone.
• We investigate how galaxy and matter bispectra can distinguish between the two non-Gaussian parameters fNL and gNL, whose effects give nearly degenerate contributions to the power spectra.