# Inflationary predictions for scalar and tensor fluctuations reconsidered.

@article{Boyle2006InflationaryPF, title={Inflationary predictions for scalar and tensor fluctuations reconsidered.}, author={Latham A. Boyle and Paul J. Steinhardt and Neil Turok}, journal={Physical review letters}, year={2006}, volume={96 11}, pages={ 111301 } }

We reconsider the predictions of inflation for the spectral index of scalar (energy density) fluctuations (ns) and the tensor/scalar ratio (r) using a discrete, model-independent measure of the degree of fine-tuning required to obtain a given combination of (ns, r ). We find that, except for cases with numerous unnecessary degrees of fine-tuning, ns is less than 0.98, measurably different from exact Harrison-Zel'dovich. Furthermore, if ns >or= 0.95, in accord with current measurements, the…

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