Moreno Filho, Marcos George MagalhãesNery, Ranieri VieiraDuarte, CristhianoAraujo, Rafael Chaves Souto2025-04-092025-04-092022-08-24MORENO, George; NERY, Ranieri; DUARTE, Cristhiano; ARAUJO, Rafael Chaves Souto. Events in quantum mechanics are maximally non-absolute. QUANTUM, v. 6, p. 785, 2022. DOI 10.22331/q-2022-08-24-785. Disponível em: https://quantum-journal.org/papers/q-2022-08-24-785/. Acesso em: 18 mar. 2025.https://repositorio.ufrn.br/handle/123456789/63429The notorious quantum measurement problem brings out the difficulty to reconcile two quantum postulates: the unitary evolution of closed quantum systems and the wave-function collapse after a measurement. This problematics is particularly highlighted in the Wigner's friend thought experiment, where the mismatch between unitary evolution and measurement collapse leads to conflicting quantum descriptions for different observers. A recent no-go theorem has established that the (quantum) statistics arising from an extended Wigner's friend scenario is incompatible when one try to hold together three innocuous assumptions, namely no-superdeterminism, parameter independence and absoluteness of observed events. Building on this extended scenario, we introduce two novel measures of non-absoluteness of events. The first is based on the EPR2 decomposition, and the second involves the relaxation of the absoluteness hypothesis assumed in the aforementioned no-go theorem. To prove that quantum correlations can be maximally non-absolute according to both quantifiers, we show that chained Bell inequalities (and relaxations thereof) are also valid constraints for Wigner's experimentAttribution 3.0 Brazilhttp://creativecommons.org/licenses/by/3.0/br/Quantum mechanicQuantum measurementarticlehttps://doi.org/10.22331/q-2022-08-24-785