Primordial density perturbation in effective loop quantum cosmology
نویسندگان
چکیده
It is widely believed that a quantum field fluctuation in an inflating background creates the primeval seed perturbation which through subsequent evolution leads to the observed large-scale structure of the universe. The standard inflationary scenario produces a scale-invariant power spectrum quite generically but it produces, unless fine tuned, too large an amplitude for the primordial density perturbation observed. Using similar techniques, it is shown that a loop quantum cosmology induced inflationary scenario can produce a scale-invariant power spectrum as well as a small amplitude for the primordial density perturbation without fine tuning. Further, its power spectrum has a qualitatively distinct feature which is in principle falsifiable by observation and can distinguish it from the standard inflationary scenario. PACS numbers: 04.60.Pp, 04.60.Kz, 98.80.Jk
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