Effect of relativity and vacuum fluctuations on quantum measurement

TL;DR

This paper demonstrates that relativistic invariance can eliminate vacuum fluctuations in the space-like spectrum, enabling noiseless measurement of single quantum particles like electrons or photons.

Contribution

It introduces a relativistic invariance-based approach to remove vacuum fluctuation noise, allowing for fundamental noiseless quantum measurements.

Findings

Vacuum fluctuations vanish for space-like spectra at zero temperature.

Relativistic invariance enables noiseless measurement of single particles.

Proposes a Sagnac interferometer scheme for practical implementation.

Abstract

Vacuum fluctuations can obscure the detection signal of the measurement of the smallest quantum objects like single particles seemingly implying a fundamental limit to measurement accuracy. However, as we show relativistic invariance implies the disappearance of fluctuations for the space-like spectrum of an observable at zero temperature. This complete absence of noise can be harnessed to perform noiseless measurement of single particles, as we illustrate for electrons or photons. We outline a general scheme to illustrate the noiseless measurement involving the space-like spectrum of observables based on the self-interference of counter-propagating paths of a single particle in a triangular Sagnac interferometer.