Randomly measured quantum particles and thermal noise
Phys. Rev. A 114, 012205 – Published 10 July, 2026
DOI: https://doi.org/10.1103/55w8-jy76
Abstract
We consider the motion of a quantum particle whose position is measured in random places at random moments in time. We contrast this motion with the motion of a quantum particle in a potential which varies randomly in space and in time, which could also be thought of as (possibly thermal) noise. We calculate expectations of observables both linear and nonlinear in the density matrix. We demonstrate explicitly that while linear observables cannot distinguish between random measurements and random noise, measurable distinctions can be seen in nonlinear observables.
