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arXiv · 1710.08408

Can power spectrum observations rule out slow-roll inflation?

J. P. P. Vieira·Christian T. Byrnes·Antony Lewis
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Abstract

The spectral index of scalar perturbations is an important observable that allows us to learn about inflationary physics. In particular, a detection of a significant deviation from a constant spectral index could enable us to rule out the simplest class of inflation models. We investigate whether future observations could rule out canonical single-field slow-roll inflation given the parameters allowed by current observational constraints. We find that future measurements of a constant running (or running of the running) of the spectral index over currently available scales are unlikely to achieve this. However, there remains a large region of parameter space (especially when considering the running of the running) for falsifying the assumed class of slow-roll models if future observations accurately constrain a much wider range of scales.

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J. P. P. Vieira, Christian T. Byrnes, Antony Lewis. 2017-10-23. Can power spectrum observations rule out slow-roll inflation?. https://doi.org/10.1088/1475-7516%2F2018%2F01%2F019

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