| Full text | |
| Author(s): |
Rossi, Vinicius P.
;
Soares-Pinto, Diogo O.
Total Authors: 2
|
| Document type: | Journal article |
| Source: | PHYSICAL REVIEW A; v. 103, n. 5, p. 13-pg., 2021-05-14. |
| Abstract | |
In 1962, Eugene P. Wigner [in Philosophical Reflections and Syntheses (Springer, Berlin, 1995), p. 247] introduced a thought experiment that highlighted the incompatibility in quantum theory between unitary evolution and wave function reduction in a measurement. This work resulted in a class of thought experiments often called Wigner's friend scenarios, which have been providing insights over many frameworks and interpretations of quantum theory. Recently, a no-go theorem obtained by D. Frauchiger and R. Renner [Nat. Commun. 9, 3711 (2018)] brought attention back to the Wigner's friend and its potential of putting theories to the test. Many answers to this result pointed out how timing in the thought experiment could be yielding a paradox. In this work, we ask what would happen if the isolated friend in a Wigner's friend scenario did not share a time reference frame with the outer observer, and time were tracked by a quantum clock. For this purpose, we recollect concepts provided by the theory of quantum reference frames and the quantum resource theory of asymmetry, to learn how to internalize time in this scenario, and introduce a model for a feasible quantum clock proposed by M. P. Woods, R. Silva, and J. Oppenheim [Ann. Henri Poincare 20, 125 (2019)] called the quasi-ideal clock. Our results have shown that this approach produces no decoherent behavior, and the disagreement between the superobserver and its friend persists even for an imprecise clock on Wigner's side. However, the Gaussian spread of this clock model can control which observables do not raise a paradox, indicating the relevance of deepening this analysis. (AU) | |
| FAPESP's process: | 17/03727-0 - Quantumness of composite systems: geometry, dynamics and thermodynamics |
| Grantee: | Diogo de Oliveira Soares Pinto |
| Support Opportunities: | Regular Research Grants |