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تسجيل مستخدم جديدConstraints on the birth of the universe and origin of cosmic dark flow
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We summarize three recent efforts to constrain the first few moments of cosmic creation before and during the epoch of inflation. We consider two means to explain a slight dip in the power spectrum of the cosmic microwave background for multipoles in the range of $ell= 10-30$ from both the {it Planck} and {it WMAP} data. We show that such a dip could be the result of resonant creation of a massive particle that couples to the inflaton field. For best-fit models, the epoch of resonant particle creation reenters the horizon at wave numbers of $k_* sim 0.00011 pm 0.0004 $ ($h$ Mpc$^{-1}$). The amplitude and location of these features correspond to the creation of a number of degenerate fermion species of mass $sim 15/lambda^{3/2} $ $m_{pl}$ during inflation where $lambda$ is the coupling constant between the inflaton field and the created fermion species. Alternatively, one can explain the existence of such a dip as due to a jump in the inflation generating potential. We show that such a jump can also resolve the excessively large dark flow predicted from the M-theory landscape. Finally, we summarize our efforts to quantify constraints on the cosmic dark flow from a new analysis of the Type Ia supernova distance-redshift relation.
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