Retraction Note: Sub-second periodicity in a fast radio burst - Bridget C. Andersen; Kevin Bandura; Mohit Bhardwaj; P. J. Boyle; Charanjot Brar; Daniela Breitman; Tomas Cassanelli; Shami Chatterjee; Pragya Chawla; Jean-François Cliche; Davor Cubranic; Alice P. Curtin; et al. (Nature, 2026)