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William Unruh

1945– · Quantum gravity, General relativity, Quantum field theory
Canadian physicist, known for the discovery of the Unruh effect: an accelerated observer in a vacuum perceives thermal radiation with a temperature proportional to the acceleration. This phenomenon links quantum field theory with general relativity and has profound implications for black holes and quantum gravity.

Biography

Born in the USA, but spent most of his career in Canada. Studied at Princeton, received PhD under the supervision of John Wheeler. Professor at the University of British Columbia. Winner of numerous awards, fellow of the Royal Society of Canada and the Royal Society of London.

Key discoveries

💡 Unruh is an avid cyclist and uses a bicycle racing analogy to explain the effect: 'If you ride fast enough, you get hot from quantum fluctuations.' The Unruh effect has not yet been experimentally confirmed due to extremely small temperatures.
Quote: "What is emptiness for one observer is a thermal bath of particles for another. Reality depends on motion."
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Related tags
black holeentropyQuantum FieldTime dilation
Related laws
Unruh effect
Related scientists
Fritz ZwickyJacob BekensteinSubrahmanyan ChandrasekharRainer WeissStephen HawkingKarl SchwarzschildJohn Archibald WheelerWilhelm Wien

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