Wigner Friend scenarios with non-invasive weak measurements
- URL: http://arxiv.org/abs/2008.09003v2
- Date: Thu, 26 Nov 2020 11:11:25 GMT
- Title: Wigner Friend scenarios with non-invasive weak measurements
- Authors: A. Matzkin and D. Sokolovski
- Abstract summary: Wigner Friend scenarios give rise to possible inconsistencies due to the ambiguous character of quantum measurements.
We show that weakly coupled probes indicate to the external agents how to obtain consistent predictions.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Wigner Friend scenarios -- in which an external agent describes quantum
mechanically a laboratory in which a Friend is making a measurement -- give
rise to possible inconsistencies due to the ambiguous character of quantum
measurements. In this work, we investigate Wigner Friend scenarios in which the
external agents can probe in a non-invasive manner the dynamics inside the
laboratories. We examine probes that can be very weakly coupled to the systems
measured by the Friends, or to the pointers or environments inside the
laboratories. These couplings, known as Weak Measurements, are asymptotically
small and do not change the outcomes obtained by the Friends nor their
probabilities. Within our scheme, we show that the weakly coupled probes
indicate to the external agents how to obtain consistent predictions,
irrespective of the possible inconsistencies of quantum measurement theory.
These non-invasive couplings could be implemented with present-day
technologies.
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