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Bounds on Cubic Lorentz-Violating Terms in the Fermionic Dispersion Relation

O. Bertolami·J. G. Rosa
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Abstract

We study the recently proposed Lorentz-violating dispersion relation for fermions and show that it leads to two distinct cubic operators in the momentum. We compute the leading order terms that modify the non-relativistic equations of motion and use experimental results for the hyperfine transition in the ground state of the ${}^9\textrm Be^+$ ion to bound the values of the Lorentz-violating parameters $η_1$ and $η_2$ for neutrons. The resulting bounds depend on the value of the Lorenz-violating background four-vector in the laboratory frame.

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O. Bertolami, J. G. Rosa. 2005-05-11. Bounds on Cubic Lorentz-Violating Terms in the Fermionic Dispersion Relation. https://doi.org/10.1103/physrevd.71.097901

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