Constraining spacetime nonmetricity with neutron spin rotation in liquid 4 He

Ralf Lehnert, W.M. Snow, Zhi Xiao, Rui Xu
2017 Physics Letters B  
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 ζ^(6)_2S_000 parameter as well as the first measurement of nonmetricity inside matter.
doi:10.1016/j.physletb.2017.07.059 fatcat:zhmf3eemm5erlhdoasbb7nytge