The Problems of Physics, Reconsidered: A Conversation with Tony Leggett

Gordon Baym, Eduardo Fradkin

Tony Leggett (1938-2026) was one of the great theoretical physicists of his generation, specializing in the quantum mechanics of fluids and solids. Rightly recognized by the 2003 Nobel Prize in Physics for his explanation of the experiments discovering the superfluidity of helium-3, he will be remembered equally for his pioneering inquiries into the transition from the quantum to the classical world and the extent to which we can observe quantum phenomena on macroscopic scales.

Alfred Romer

Edwin Cartlidge

Tony Leggett has two questions that he likes to ask audiences of physicists.The first concerns the double-slit experiment with single electrons: does each electron pass through just one of the slits to make the interference pattern? The second is about Schrödinger's famous thought experiment with a cat in a box: will the cat definitely be either alive or dead before the box is opened?

W. Macdonald Smith

Erkki Brändas

Karl Hess

My first contact with Hans and Kristel was, as just mentioned, through e-mail exchanges. We commiserated about how easy it was to get something published that indicated a violation of Bell’s inequality and how complicated it was to publish anything opposed to the gospel of Bell. I also brought Tony Leggett’s work with Anupam Garg to the attention of Kristel and Hans and we started a detailed correspondence and very soon a collaboration that resulted in a visit of Hans and Kristel in Hawaii.