Uncovering the History of Cosmic Inflation from Anomalies in Cosmic
  Microwave Background Spectra
  We propose an inflationary primordial feature model that can explain both the
large and small-scale anomalies in the currently measured cosmic microwave
background (CMB) anisotropy spectra, revealing a clip of adventurous history of
the Universe during its primordial epoch. Although the model is currently
statistically indistinguishable from the Standard Model, we show that future
observations such as the Simons Observatory and LiteBIRD will complement each
other in distinguishing the model differences due to their accurate E-mode
polarization measurements, and the PICO mission, if funded, can put stringent
constraints on all characteristic properties. The model predicts a signal of
classical primordial standard clock, which can also be used to distinguish the
inflation and alternative scenarios in a model-independent fashion.
