BICEP/Keck XIII Lowers the Limit on Cosmic Inflation

A new paper, “BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season”, has lowered the limit on primordial gravitational waves which would provide evidence for the popular theory of cosmological inflation. The paper, which combines data from the BICEP2, BICEP3, and Keck Array instruments at the South Pole and the Planck spacecraft, has improved the constraints on the presence of B-mode polarisation in the cosmic microwave background radiation by a factor of two, which rules out almost all of the simple models of inflation as originally proposed. While theorists have proposed more complex models that still fit under the new constraints, it’s getting claustrophobic under the new curve.

Note that many models of the multiverse predict the primordial gravitational waves that have, so far, failed to be detected.

1 Like