Llewellyn H. Thomas

American physicist

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July 14, 2026

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Llewellyn H. Thomas was an American physicist known for discovering Thomas precession. This phenomenon describes the precessional motion of an orbital electron's spin axis. It is caused by the interaction between the electron's spin and the electric field generated by the nucleus. Thomas's work contributed to the understanding of atomic physics and the behavior of subatomic particles.

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particle accelerator
Sector-focused cyclotrons
…was discovered in 1938 by Llewellyn H. Thomas, then at Ohio State University, but was not applied until the alternating-gradient synchrotron was invented in 1952. Several of these devices, sometimes called azimuthally varying field (AVF) cyclotrons, have been built for use in nuclear and medical research. The world’s largest cyclotron,…
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…was discovered in 1938 by Llewellyn H. Thomas, then at Ohio State University, but was not applied until the alternating-gradient synchrotron was invented in 1952. Several of these devices, sometimes called azimuthally varying field (AVF) cyclotrons, have been built for use in nuclear and medical research. The world’s largest cyclotron,…
Read More