Two clouds as the 19th century draws to a close
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The scene is familiar: in 1900, William Thomson (1824–1907), better known as Lord Kelvin and one of the greatest physicists of the 19th century, spoke of the extraordinary advances science had made over the century then drawing to a close. Yet two clouds, he added, somewhat darkened this assessment. These were the negative result of the Michelson–Morley experiment and the discrepancy between theory and experiment in black-body radiation (see Mathématiques et Physique, Bibliothèque Tangente 69, 2019, and Équations de la physique moderne, Bibliothèque Tangente 71, 2020).
The first would lead to special relativity and a new conception of time and space. The second would lead Max Planck to quantum theory in 1900.
