Using classical (non-quantum, that is) electrodynamics, one can predict that a charged particle accelerated by a nonuniform electric field will radiate. This can be modeled (although not without problems, such as unphysical runaway solutions) by the Abraham–Lorentz force, which is a dissipative force proportional to the rate of change of the acceleration.(adsbygoogle = window.adsbygoogle || []).push({});

Now, a general argument known as the fluctuation-dissipation theorem says that if a system has a dissipative force, then there must be a corresponding fluctuation. If one applies the fluctuation-dissipation theorem to the Abraham-Lorentz force, one would get a fluctuation in the electromagnetic field, I assume.

If this is true, it's sort of amazing, because the Abraham-Lorentz force is derived fromclassicalelectrodynamics. But it seems to point to a result from quantum field theory, that the electromagnetic field inherently has fluctuations.

Does anyone know of a paper working out the fluctuations predicted by the fluctuation-dissipation theorem applied to the electromagnetic field? How does the predicted fluctuations compare with the predictions made by QED?

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Fluctuation-Dissipation Theorem and QED

Loading...

Similar Threads - Fluctuation Dissipation Theorem | Date |
---|---|

I Are the energy fluctuations in space real or virtual? | Jan 18, 2018 |

I So, do vacuum fluctuations exist? | Oct 10, 2017 |

A Can Fluctuation-Dissipation Theorem Apply to Magnetic Forces | Jul 21, 2016 |

Dissipation function in fluctuation dissipation theory | Jan 15, 2015 |

**Physics Forums - The Fusion of Science and Community**