Quantum Fluctuations of Fields and Stress Tensors

TL;DR

This review discusses recent findings on quantum fluctuations of electric fields and stress tensors, highlighting their probability distributions, physical effects, and measurement sensitivities.

Contribution

It synthesizes recent research on quantum fluctuation distributions and their physical implications, emphasizing the role of measurement methods.

Findings

Vacuum electric field fluctuations follow a Gaussian distribution.

Quadratic operators like energy density have heavy-tailed distributions.

Large fluctuations are highly sensitive to measurement procedures.

Abstract

This is a review of recent work on quantum fluctuations of the electric field and of stress tensor operators and their physical effects. The probability distribution for vacuum fluctuations of the electric field is Gaussian, but that for quadratic operators, such as the energy density, can have a more slowly decreasing tail, leading to an enhanced probability of large fluctuations. This effect is very sensitive to the details of how the measurement is performed. Some possible physical effects of these large fluctuations will be discussed.