Consistency of Planck Data With Power-law Primordial Scalar Power Spectrum

Abstract In this work we explore the possibility of variations in primordial scalar power spectrum around power-law shape, as predicted by single-field slow-roll inflationary scenarios. We search for a trace these fluctuations semiblind, model-independent way observations cosmic microwave background (CMB) sky. particular, use two sets perturbation patterns, specific patterns with typical features such oscillations, bumps, and transitions, well modes, constructed from eigenanalysis forecasted or measured covariance parameters. These principle, span parameter space all possible perturbations to and, when rank ordered, ones highest detectability would suffice constrainable data-driven (and not theoretically biased) manner. With Planck measurements CMB anisotropies, amplitudes considered are found be consistent zero. This finding confirms, absence theoretical biases, consistency data assumption pattern spectrum.