Spectral index and its running with deviation from the “slow-roll”
نویسنده
چکیده
A deviation from the slow roll may shift the spectral index and its running. Such a deviation is very generic in inflationary models since the slow-roll equation is not the exact solution of the field equation. We calculate the spectral index and its running with non-vanishing deviation parameter, showing that the deviation parameter is a “hidden” parameter of the standard calculation. A running spectral index scenario in which the spectral index runs from blue (n > 1) on large length scales to red (n < 1) on short length scales is examined.
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