Can power spectrum observations rule out slow-roll inflation?

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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Cited by in corpus (7)

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• Generation of inflationary perturbations in the continuous spontaneous localization model: The second order power spectrum
• Graviton backreaction on the local cosmological expansion in slow-roll inflation
• The Quest for the Inflationary Spectral Runnings in the Presence of Systematic Errors
• Observational constraints on the second-order primordial power spectrum: Exploring a Continuous Spontaneous Localization inspired inflationary model