We analyze the spectrum of density perturbations generated in models of the\nrecently discovered "D-cceleration" mechanism of inflation. In this scenario,\nstrong coupling quantum field theoretic effects sum to provide a DBI-like\naction for the inflaton. We show that the model has a strict lower bound on the\nnon-Gaussianity of the CMBR power spectrum at an observable level, and is thus\nfalsifiable. This in particular observationally distinguishes this mechanism\nfrom traditional slow roll inflation generated by weakly interacting scalar\nfields. The model also favors a large observable tensor component to the CMBR\nspectrum.\n
We present a detailed analytical study of ultra-relativistic neutrinos in cosmological perturbation theory and of the observable signatures of inhomogeneities in the cosmic neut...
We calculate predictions from wide class of `active' models of cosmic\nstructure formation which allows us to scan the space of possible defect\nmodels. We calculate the linear ...
The existence of a cosmic neutrino background can be probed indirectly by CMB experiments, not only by measuring the background density of radiation in the universe, but also by...
We examine the possibility that a significant component of the energy density of the universe has an equation-of-state different from that of matter, radiation or cosmological c...
We propose a comprehensive theory of dark matter that explains the recent proliferation of unexpected observations in high-energy astrophysics. Cosmic ray spectra from ATIC and ...
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