One of France’s oldest science museums, the Ampère Museum, has just revealed a treasure hidden in its reserves: the only complete and authentic version of the Einstein-de Haas experiment, a rare experimental work published by Albert Einstein himself.

This extraordinary discovery, the result of research by Alfonso San Miguel, a researcher at the Institut Lumière Matière – iLM (Claude Bernard Lyon 1 University / CNRS), in partnership with Bernard Pallandre, a volunteer curator at the museum, is detailed in an upcoming article in Europhysics News.

The invaluable experimental apparatus recently found at the Ampère Museum near Lyon is the only fundamental research experimental work published by Albert Einstein. In 1915, together with the Dutch physicist Wander de Haas, it allowed him to demonstrate the existence of Ampère’s molecular currents.

This prediction unified the understanding of certain magnetic phenomena and contributed to the understanding of orbiting electrons, marking a key moment in the history of physics.

Several months of research were necessary to make this discovery, led by Alfonso San Miguel, a researcher at iLM and also President of the Société des Amis d’André-Marie Ampère, an association that has managed the Ampère Museum since its creation in 1931.

In collaboration with Bernard Pallandre, a volunteer curator at the museum, they were able to trace the object through letters and other texts, until they found and authenticated the experiment, donated by Mrs. de Haas in the late fifties.

We unearthed old documents indicating that Mrs. de Haas, who was also a physicist, had given us an original version of the famous Einstein-de Haas experiment, the only one on which Einstein, that great theorist, had published. After several months of searching and several twists and turns, we finally found the object in the museum’s reserves on March 7, 2023. The object had never been inventoried. It took a few more months to authenticate it and be certain that we had found the only complete copy of the only experiment that Einstein had experimented with and published, explains Alfonso San Miguel.

This find from the reserves of the Ampère Museum revives a crucial chapter in our scientific heritage, linking past and present in an extraordinary way. In an article to be published in Europhysics News, A. San Miguel and B. Pallandre present the object that allowed Einstein and de Haas to concretely demonstrate the existence of electron orbits through a visible oscillatory motion.

The discovered object and modern interactive models will be exhibited from mid-April at the Ampère Museum.


CNRS | Alfonso San Miguel, Bernard Pallandre, Revisiting the Einstein-de Haas Experiment: the Ampère Museum’s Hidden Treasure

  • Share this article:

Discover more from LBV Magazine English Edition

Subscribe to get the latest posts sent to your email.

Something went wrong. Please refresh the page and/or try again.