Physicist who received the Nobel Prize for his work confirming the structure of matter. The Curies were next-door neighbours and professional colleagues (though Perrin, younger and better-connected, was awarded a position they coveted). Einstein wrote complementing him on the precision of his observations of Brownian motion (which assisted in Einstein’s own work). Lévi-Strauss knew him right at the end of his life, in New York, where they helped set up an institution for exiled French academics.