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arXiv · 1707.09630

Constraining Spacetime Nonmetricity with Neutron Spin Rotation in Liquid He-4

Ralf Lehnert·W. M. Snow·Zhi Xiao·Rui Xu
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Abstract

General spacetime nonmetricity coupled to neutrons is studied. In this context, it is shown that certain nonmetricity components can generate a rotation of the neutron's spin. Available data on this effect obtained from slow-neutron propagation in liquid helium are used to constrain isotropic nonmetricity components at the level of $10^{-22}\,$GeV. These results represent the first limit on the nonmetricity $\zeta^{(6)}_2S_{000}$ parameter as well as the first measurement of nonmetricity inside matter.

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Ralf Lehnert, W. M. Snow, Zhi Xiao, Rui Xu. 2017-07-30. Constraining Spacetime Nonmetricity with Neutron Spin Rotation in Liquid He-4. https://doi.org/10.1016/j.physletb.2017.07.059

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