Walnut Creek Man Wins Nobel Prize In Physics

A Walnut Creek-based physicist was named a co-winner of the Nobel Prize in Physics on Tuesday for his pioneering work on quantum information science.

John Clauser, 79, will share the nearly $900,000 prize with two fellow physicists who followed in his footsteps: Alain Aspect, of Universite Paris-Saclay and Ecole Polytechnique in France, and Anton Zeilinger, of the University of Vienna in Austria.

Clauser’s work helped prove that two particles, once linked quantum mechanically, or entangled, can be separated by large distances — even the diameter of the universe — and still “know” what happens to one another.

The discovery stemmed from a test experiment conducted in the sub-basement of Birge Hall at the University of California, Berkeley, where he was a postdoctoral researcher back in 1971. Alongside Stuart Freedman, a physicist and a graduate student at the time, Clauser measured “quantum entanglement” and showed that the photons could act in concert despite being physically separated.

After the initial experiment, Clauser continued to refine the research to provide more convincing proof that nature violates what’s called Bell’s inequality and prove that the quantum mechanical description of entangled particles is right, and can’t be replaced by the hidden variable theory.

While proving groundbreaking today, Clauser’s research was discouraged by many physicists at the time.

He recalled having little money for the experiments and having to “cobble together old junk or scrap from the UC Physics Department” and build everything from scratch.

“I was having fun. It was a challenging experiment. I thought it was important at the time, even though everybody told me I was crazy and was going to ruin my career by doing it,” said Clauser during a phone interview with Nobel Prize Outreach.

Clauser said he had great difficulty finding a professor position due to the unappealing research, and therefore went off to Lawrence Livermore National Laboratory to do controlled fusion plasma physics experiments.

“I proved that I was a decent experimentalist by doing these experiments,” Clauser said.

Entangled particles are at the core of today’s quantum computers. Qubits, the basic units of information in quantum computing, are linked in a single quantum state that, with the right manipulation, could potentially out-compute today’s powerful digital computers.

Entanglement at larger distances is also crucial to China’s quantum-encrypted communications satellite, Micius, which relies on quantum entanglement between photons that are separated by thousands of kilometers.

“It has become increasingly clear that a new kind of quantum technology is emerging,” said Anders Irback, chair of the Nobel Committee for Physics. “We can see that the laureates’ work with entangled states is of great importance, even beyond the fundamental questions about the interpretation of quantum mechanics.”