A no-go theorem for the persistent reality of Wigner’s friend’s perception / Papers QISS1 / By Qiss Philippe Allard Guérin, Veronika Baumann, Flavio Del Santo, Časlav Brukner Perimeter Institute, IQOQI IQOQI Vienna Preprint: 2009.09499Journal: Commun Phys 4, 93 (2021)