Measurements of a key parameter in cosmology do not agree. Is this the sign of exciting new physics, do we need to rethink some aspects of cosmology or is it just a measurement error? In this film, Nobel Prize winning physicist Adam Reiss, and George Efstathiou (who was the scientist chose to give the cosmology results for ESa's Planck Probe) are joined by astrophysicist Daniel Mortlock and theoretical cosmologist Claudia de Rham to discuss this latest puzzle for cosmology.
