Topic
Thomas precession
About: Thomas precession is a research topic. Over the lifetime, 392 publications have been published within this topic receiving 6617 citations.
Papers published on a yearly basis
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Papers
TL;DR: In this article, the precession of a particle moving in a homogeneous electromagnetic field has been investigated for spin ½ particles in some particular cases and the results were derived by explicit use of the Dirac equation with the occasional inclusion of a Pauli term to account for an anomalous magnetic moment.
Abstract: The problem of the precession of the “spin” of a particle moving in a homogeneous electromagnetic field — a problem which has recently acquired considerable experimental interest — has already been investigated for spin ½ particles in some particular cases.1 In the literature the results were derived by explicit use of the Dirac equation, with the occasional inclusion of a Pauli term to account for an anomalous magnetic moment. On the other hand, following a remark of Bloch2 in connection with the nonrelativistic case, the expectation value of the vector operator representing the “spin” will necessarily follow the same time dependence as one would obtain from a classical equation of motion. To solve the problem for arbitrary spin in the relativistic case, it will thus suffice to produce a consistent set of covariant classical equations of motion. Such equations have been indicated a long time ago by Frenkel3 and are discussed by Kramers.4 These authors use an antisymmetric tensor M as the relativistic generalization of the intrinsic angular momentum observed in the rest-frame of the particle. A formulation in terms of the (axial) four-vector s which describes the polarization in a covariant fashion5 — though basically equivalent — is however much more convenient for our problem. We shall therefore derive first the equations of motion directly in terms of this four-vector s.
1,318 citations
TL;DR: In this paper, it was shown that the value of the spin axis in an external magnetic field required to account for Zeeman effects seemed to lead to doublet separations twice those which are observed.
Abstract: IN a letter published in NATURE of February 20, p. 264, Messrs. Uhlenbeck and Goudsmit have shown how great difficulties which atomic theory had met in the attempt to explain spectral structure and Zeeman effects, can be avoided by using the idea of the spinning electron. Although their theory is in complete qualitative agreement with observation, it involved an apparent quantitative discrepancy. The value of the precession of the spin axis in an external magnetic field required to account for Zeeman effects seemed to lead to doublet separations twice those which are observed. This discrepancy, however, disappears when the kinematical problem concerned is examined more closely from the point of view of the theory of relativity.
783 citations
TL;DR: A single free spin- 1 / 2 particle is considered and the reduced density matrix for its spin is not covariant under Lorentz transformations and the spin entropy is not a relativistic scalar and has no invariant meaning.
Abstract: We consider a single free spin- $\frac{1}{2}$ particle. The reduced density matrix for its spin is not covariant under Lorentz transformations. The spin entropy is not a relativistic scalar and has no invariant meaning.
343 citations
TL;DR: In this paper, a 3×3 parametric, unimodular, orthogonal matrix that represents the Thomas rotation is presented and studied, which enables the Lorentz transformation group to be parametrized by two physical observables: the (3-dimensional) relative velocity and orientation between inertial frames.
Abstract: Two successive pure Lorentz transformations are equivalent to a pure Lorentz transformation preceded by a 3×3 space rotation, called a Thomas rotation. When applied to the gyration of the rotation axis of a spinning mass, Thomas rotation gives rise to the well-knownThomas precession. A 3×3 parametric, unimodular, orthogonal matrix that represents the Thomas rotation is presented and studied. This matrix representation enables the Lorentz transformation group to be parametrized by two physical observables: the (3-dimensional) relative velocity and orientation between inertial frames. The resulting parametrization of the Lorentz group, in turn, enables the composition of successive Lorentz transformations to be given by parameter composition. This composition is continuously deformed into a corresponding, well-known Galilean transformation composition by letting the speed of light approach infinity. Finally, as an application the Lorentz transformation with given orientation parameter is uniquely expressed in terms of an initial and a final time-like 4-vector.
167 citations
TL;DR: In this paper, it is shown that the gravitomagnetic precession of a gyroscope is intimately connected with the special temporal structure around a rotating mass that is revealed by the clock effect, and the implications of this effect for the notion of inertial dragging in the general theory of relativity are presented.
Abstract: The main theoretical aspects of gravitomagnetism are reviewed. It is shown that the gravitomagnetic precession of a gyroscope is intimately connected with the special temporal structure around a rotating mass that is revealed by the gravitomagnetic clock effect. This remarkable effect, which involves the difference in the proper periods of a standard clock in prograde and retrograde circular geodesic orbits around a rotating mass, is discussed in detail. The implications of this effect for the notion of “inertial dragging” in the general theory of relativity are presented. The theory of the clock effect is developed within the PPN framework and the possibility of measuring it via spaceborne clocks is examined.
128 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 4 |
| 2020 | 6 |
| 2019 | 8 |
| 2018 | 7 |
| 2017 | 10 |
| 2016 | 9 |