Flavor-oscillation clocks, continuous quantum measurements and a violation of Einstein equivalence principle

TL;DR

This paper investigates how continuous quantum measurements of flavor-oscillation clocks in gravitational fields reveal violations of Einstein's equivalence principle, showing discrepancies in oscillation frequencies and measurement distributions.

Contribution

It demonstrates that flavor-oscillation clocks under continuous measurement violate Einstein's equivalence principle in two distinct ways.

Findings

Oscillation frequency in free fall differs from general relativity predictions.

Measurement output distributions in free fall do not match Minkowski spacetime results.

Violation of Einstein equivalence principle observed in quantum measurement context.

Abstract

The relation between Einstein equivalence principle and a continuous quantum measurement is analyzed in the context of the recently proposed flavor-oscillation clocks, an idea pioneered by Ahluwalia and Burgard (Gen. Rel Grav. Errata 29, 681 (1997)). We will calculate the measurement outputs if a flavor-oscillation clock, which is immersed in a gravitational field, is subject to a continuous quantum measurement. Afterwards, resorting to the weak equivalence principle, we obtain the corresponding quantities in a freely falling reference frame. Finally, comparing this last result with the measurement outputs that would appear in a Minkowskian spacetime it will be found that they do not coincide, in other words, we have a violation of Einstein equivalence principle. This violation appears in two different forms, namely: (i) the oscillation frequency in a freely falling reference frame does not match with the case predicted by general relativity, a feature previously obtained by Ahluwalia; (ii) the probability distribution of the measurement outputs, obtained by an observer in a freely falling reference frame, does not coincide with the results that would appear in the case of a Minkowskian spacetime.