Did Leonardo, Tyndall, Rayleigh, Einstein and Smoluchowski argue about why the sky is blue?
Research question: What did Leonardo da Vinci, John Tyndall, Lord Rayleigh, Albert Einstein, and Marian Smoluchowski each contribute to explaining why the sky is blue, what debates arose between them about scattering and density fluctuations, and where does that historical understanding stand as of 2026?
The records show that Smoluchowski provided a thermodynamic explanation for critical opalescence by attributing it to accidental density deviations and deriving an expression for mean density fluctuation based on compressibility 12. Einstein contributed by applying Maxwell's equations to derive the intensity of light scattered due to these density deviations 3. The exchange of letters between Smoluchowski and Einstein contributed essentially to the solution of the problem of density fluctuations 8. The provided facts do not contain information regarding the contributions of Leonardo da Vinci, John Tyndall, or Lord Rayleigh, nor do they specify the status of this historical understanding as of 2026.
Sources
"An explanation of the phenomenon on thermodynamic principles as due to the accidental deviations of density arising in the substance was put forward by Smoluchowski."The molecular scattering of light in vapours and in liquids and its relation to the opalescence observed in the critical state (1922)
"He obtained an expression for the mean fluctuation of density in terms of the compressibility of the substance"The molecular scattering of light in vapours and in liquids and its relation to the opalescence observed in the critical state (1922)
"later, Einstein applied Maxwell’s equations of the electromagnetic field to obtain an expression for the intensity of the light scattered in consequence of such deviations of density."The molecular scattering of light in vapours and in liquids and its relation to the opalescence observed in the critical state (1922)
"He, before Einstein, refuted the Naegeli–Ramsey objection9:"Einstein–Perrin dilemma on the Brownian motion (Avogadro’s number) resolved? (2024)
"Keesom tested this formula over a range of 2·35° above the critical point of ethylene and found good agreement except very close to the critical point."The molecular scattering of light in vapours and in liquids and its relation to the opalescence observed in the critical state (1922)
"This paper was a German translation of his former paper published in 1906 in Polish (Smoluchowski 1906b) and French (Smoluchowski 1906c)."Einstein–Perrin dilemma on the Brownian motion (Avogadro’s number) resolved? (2024)
"On 7 September 1906, the editor of Annalen der Physik received an article written by"Einstein–Perrin dilemma on the Brownian motion (Avogadro’s number) resolved? (2024)
"The exchange of letters between M. Smoluchowski and Einstein contributed essentially to the solution of the problem of density fluctuations."Scientific contacts of Polish physicists with (2006)