Agreement and disagreement in a non-classical world

• DOI: 10.1098/rsta.2023.0004
• Publication Date: 2024-01-29T00:05:15Z
• Authors: Adam Brandenburger; Patricia Contrera...; Pierfrancesco La ...; Giannicola Scarpa; Kai Steverson
• Keywords: Certainty; Causality; Common knowledge (logic); Kochen–Specker theorem

The Agreement Theorem Aumann (1976 Ann. Stat. 4 , 1236–1239. ( doi:10.1214/aos/1176343654 )) states that if two Bayesian agents start with a common prior, then they cannot have knowledge hold different posterior probabilities of some underlying event interest. In short, the ‘agree to disagree’. This result applies in classical domain where probability theory applies. But non-classical domains, such as quantum world, does not apply. Inspired principally by their use mechanics, we employ signed investigate epistemics world. We find here, too, it be assign an However, domain, unlike case, can certainty Finally, probabilities, communication is possible—even take place. article part theme issue ‘Quantum contextuality, causality and freedom choice’.