Quantum Observables Cannot be Separated from their Interactions With Respected Environment: An Analysis

Monday - October 30 2023, 22:13 UTC - 1 year ago

Hiroshima University physicists recently published a study in Physical Review Research which suggest that the physical reality of an object and multiple possible realities cannot be reconciled with the same physical reality. The study demonstrated how quantum superpositions in the dynamics of a measurement interaction shape the observable reality of a system.

Whenever measurement precision nears the uncertainty limit set by quantum mechanics, the results become dependent on the interaction dynamics between the measuring device and the system. This finding may explain why quantum experiments often produce conflicting results and may contradict basic assumptions regarding physical reality.

Two quantum physicists from Hiroshima University recently analyzed the dynamics of a measurement interaction, where the value of a physical property is identified with a quantitative change in the meter state. This is a difficult problem, because quantum theory does not identify the value of a physical property unless the system is in a so-called "eigenstate" of that physical property, a very small set of special quantum states for which the physical property has a fixed value.

The researchers solved this fundamental problem by combining information about the past of the system with information about its future in a description of the dynamics of the system during the measurement interaction, demonstrating that the observable values of a physical system depend on the dynamics of the measurement interaction by which they are observed.

The team recently published the results of their study in the journal Physical Review Research.

"There is much disagreement about the interpretation of quantum mechanics because different experimental results cannot be reconciled with the same physical reality," said Holger Hofmann, professor in the Graduate School of Advanced Science and Engineering at Hiroshima University in Hiroshima, Japan.

"In this paper, we investigate how quantum superpositions in the dynamics of the measurement interaction shape the observable reality of a system seen in the response of a meter. This is a major step towards explaining the meaning of "superposition" in quantum mechanics," said Hofmann.

In quantum mechanics, a superposition describes a situation in which two possible realities seem to co-exist, even though they can be distinguished clearly when an appropriate measurement is performed. The analysis of the team’s study suggests that superpositions describe different kinds of reality when different measurements are performed. The reality of an object depends on the object’s interactions with its surroundings.

"Our results show that the physical reality of an object cannot be separated from the context of all its interactions with the environment, past, present, and future, providing strong evidence against the widespread belief that our world can be reduced to a mere configuration of material building blocks," said Hofmann.

According to quantum theory, the meter shift that represents the value of the physical property observed in a measurement depends on the dynamics of the system caused by the fluctuations of the back-action by which the meter disturbs the state of the system. Quantum superpositions between the different possible system dynamics shape the meter response and assign specific values to it.

The authors further explained that the fluctuations in the system dynamics depend on the strength of the measurement interaction. In the limit of weak interference, the observables of the system can only depend weakly on the history of the system.