Half of the ordinary baryonic matter has been tough to find but Fast Radio Bursts made it possible to detect the WHIM. Thanks to Kiwico for sponsoring this video! For 20% off go to https://kiwico.com/veritasium or use code VERITASIUM at checkout. Special thanks to Prof. Geraint Lewis https://ve42.co/gfl Nature paper: A census of baryons in the Universe from localized fast radio bursts https://ve42.co/whim Research and Writing by Max Levy, Derek Muller and Jonny Hyman Editing, Animations, Audio Mix & Mastering by Jonny Hyman Filmed by Raquel Nuno Thumbnail by Ignat Berbeci Music from Epidemic Sound https://epidemicsound.com/