Quantum Fluctuations Contribution to the Random Walk of a Single Molecule and New Estimate of the Planck Constant

TL;DR

This paper demonstrates that quantum fluctuations significantly influence the random walk of a single molecule, providing a new experimental estimate of the Planck constant and addressing debates on the standard quantum limit.

Contribution

It introduces a novel approach linking quantum fluctuations to molecular motion and offers a new estimate of the Planck constant based on experimental data.

Findings

Quantum fluctuations dominate the molecular random walk.

Experimental data supports settling the standard quantum limit controversy.

New estimate of the Planck constant:  = (1.1 1) ^{-34} J.s.

Abstract

It is shown, by considering the case of the harmonic oscillator, that quantum fluctuations may be the most significant contribution to the random walk of a single molecule. From this point, the controversy on the existence of a standard quantum limit (SQL) is addressed and settled on the experimental ground. Comparisons to the experimental data yet avalaible in the literature provide a new estimate of the reduced Planck constant yielding \hbar = (1.1 \pm 0.2) ~ 10^{-34} J.s.