Courtesy of Detlef Dürr, Ludwig Maximilian University of Munich
VIENNA—One night in 1952, Richard Feynman and David Bohm went bar-hopping in Belo Horizonte. Louisa Gilder reconstructs the night in her brilliant book on the history of quantum mechanics, The Age of Entanglement. Feynman was on a sabbatical in Rio and, ever exuberant, raved about local beers, drumming lessons, and Brazilian girls. Bohm, teaching at the University of São Paulo, never took to the place. He had just been hounded out of Princeton University and out of the U.S. by the McCarthy witch hunt. He felt exiled not just from his country but from the mainstream of physics. Bohm perked up only when Feynman expressed some fleeting interest in his new way of thinking about quantum mechanics.
Bohm had developed the first comprehensive alternative to the orthodox Copenhagen Interpretation of quantum mechanics. Building on earlier work by Einstein and Louis de Broglie, Bohm showed that quantum randomness need not be intrinsic to nature. It might simply reflect our bull-in-a-china-shop way of probing the quantum realm. In Bohm’s original formulation, particles always have well-defined positions and are shepherded by a “quantum potential” similar in general spirit to electric and gravitational forces. Because this potential operated instantaneously, linking together everything in the universe no matter how far apart it may be, Bohm later came to think that quantum physics was just the surface view of a radically holistic reality.
Physicists tend not to like Bohm’s theory, for reasons both sociological and scientific, but at the least it broke the spell of Copenhagen. Léon Rosenfeld, an especially pugnacious partisan of Copenhagen, slammed him and even worked behind the scenes to get journals to reject his papers, as if trying to complete what the McCarthyites had started. Yet Bohm’s work inspired Irish physicist John Bell to revolutionize thinking about quantum physics in the 1960s.
At a conference a few week ago, I had the pleasure of meeting Basil Hiley, Bohm’s longtime collaborator and co-author of his final book, The Undivided Universe. Hiley is a theoretical physicist at Birkbeck College of the University of London, where Bohm ended up after he couldn’t take Brazilian food anymore. What follows in an abridged transcript of our chat. Hiley, like his late mentor, has such an unconventional way of thinking about physics that I didn’t really follow much of what he said. In this transcript, I took the liberty of shifting around blocks of text and omitting passages on technical mathematics to try to make sense of it all. If it piques your interest, a good next step would be Hiley’s exhaustive Wikipedia page. If nothing else, Bohm’s theory is a good subject to talk about with a beer in hand.
Diagram courtesy of Detlef Dürr, Ludwig Maximilian University of Munich