Kelvin's clouds

TL;DR

This paper clarifies historical misconceptions about Lord Kelvin's 'clouds' in physics, emphasizing their actual content and how they have been misrepresented over time.

Contribution

It provides an accurate reinterpretation of Kelvin's original concerns, correcting common distortions in historical understanding.

Findings

Kelvin's clouds were about ether motion and energy equipartition, not blackbody radiation.

Misrepresentations of Kelvin's lecture are widespread and often inaccurate.

The paper explains reasons behind these historical distortions.

Abstract

In 1900 Lord Kelvin identified two problems for 19th century physics, two "clouds" as he puts it: the relative motion of the ether with respect to massive objects, and Maxwell-Boltzmann's theorem on the equipartition of energy. These issues were eventually solved by the theory of special relativity and by quantum mechanics. In modern quotations, the content of Kelvin's lecture is almost always distorted and misrepresented. For example, it is commonly claimed that Kelvin was concerned about the UV-catastrophe of the Rayleigh-Jeans law, while his lecture actually makes no reference at all to blackbody radiation. I rectify these mistakes and explore reasons for their occurrence.