Breaking the scale invariance of the primordial spectrum or not: the new WMAP data
نویسنده
چکیده
It seems that new WMAP data require a fit with a primordial spectrum containing small negative tilt index in addition to the featureless Harrison-Zeljdovič-Peebles spectrum thus implying a broken scale invariance. We show that the data could be otherwise interpreted by a scale invariant primordial spectrum with the scale noninvariant evolution of density contrast using the Press-Schechter formalism. The estimate of the acceleration parameter, as a source of the inhomogeneity of spacetime, is made by searching for the minima of the deviation measure defined by the Press-Schechter mass functions for this interpretation compared to the assumptions implicit in the WMAP fit.
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