Investigating Cosmic Discordance
  We show that a combined analysis of CMB anisotropy power spectra obtained by
the Planck satellite and luminosity distance data simultaneously excludes a
flat universe and a cosmological constant at $99 \%$ CL. These results hold
separately when combining Planck with three different datasets: the two
determinations of the Hubble constant from Riess et al. 2019 and Freedman et
al. 2020, and the Pantheon catalog of high redshift supernovae type-Ia. We
conclude that either LCDM needs to be replaced by a different model, or else
there are significant but still undetected systematics. Our result calls for
new observations and stimulates the investigation of alternative theoretical
models and solutions.
