Signals from the early Universe: a comprehensive search for primordial features in Planck CMB datasets
Researchers systematically searched for primordial oscillatory features in Cosmic Microwave Background (CMB) data by comparing different analysis methods and likelihood frameworks. While some indications of oscillations persist across various analyses, none reached global statistical significance. Updates using newer Planck products significantly reduced earlier anomalies, suggesting that future polarization measurements are crucial to distinguish genuine signals from noise.