CMB Anomalies after Planck
  Several unexpected features have been observed in the microwave sky at large
angular scales, both by WMAP an by Planck. Among those features is a lack of
both variance and correlation on the largest angular scales, alignment of the
lowest multipole moments with one another and with the motion and geometry of
the Solar System, a hemispherical power asymmetry or dipolar power modulation,
a preference for odd parity modes and an unexpectedly large cold spot in the
Southern hemisphere. The individual p-values of the significance of these
features are in the per mille to per cent level, when compared to the
expectations of the best-fit inflationary $\Lambda$CDM model. Some pairs of
those features are demonstrably uncorrelated, increasing their combined
statistical significance and indicating a significant detection of CMB features
at angular scales larger than a few degrees on top of the standard model.
Despite numerous detailed investigations, we still lack a clear understanding
of these large-scale features, which seem to imply a violation of statistical
isotropy and scale invariance of inflationary perturbations. In this
contribution we present a critical analysis of our current understanding and
discuss several ideas of how to make further progress.
