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Gravitational Couplings of Intrinsic Spin

Bahram Mashhoon
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Abstract

The gravitational couplings of intrinsic spin are briefly reviewed. A consequence of the Dirac equation in the exterior gravitational field of a rotating mass is considered in detail, namely, the difference in the energy of a spin-1/2 particle polarized vertically up and down near the surface of a rotating body is $\hbarΩ\sinθ$. Here $θ$ is the latitude and $Ω= 2GJ/(c^2 R^3)$, where $J$ and $R$ are, respectively, the angular momentum and radius of the body. It seems that this relativistic quantum gravitational effect could be measurable in the foreseeable future.

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Bahram Mashhoon. 2000-03-07. Gravitational Couplings of Intrinsic Spin. https://doi.org/10.1088/0264-9381%2F17%2F12%2F312

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