The non-minimal ekpyrotic trispectrum
نویسندگان
چکیده
منابع مشابه
Non-Gaussianities in New Ekpyrotic Cosmology.
The new ekpyrotic model is an alternative scenario of the early Universe which relies on a phase of slow contraction before the big bang. We calculate the 3-point and 4-point correlation functions of primordial density perturbations and find a generically large non-Gaussian signal, just below the current sensitivity level of cosmic microwave background experiments. This is in contrast with slow...
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Minimum-variance estimators for the parameter fnl that quantifies local-model non-Gaussianity can be constructed from the cosmic microwave background (CMB) bispectrum (three-point function) and also from the trispectrum (four-point function). Some have suggested that a comparison between the estimates for the values of fnl from the bispectrum and trispectrum allow a consistency test for the mod...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2016
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2016/01/026