We use the eikonal approximation in order to calculate the additional phase shift between two neutrino mass eigenstates during their propagation in a background of gravitational wave or scalar perturbations in the flat and the FRW spacetime metric. We comment on the dependence of the results on the characteristics of the perturbations, give some order-of-magnitude estimates, and find that, although small, the resulting phase difference persists for large redshifts, up to the validity of our approximations.

中文翻译：

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引力和宇宙学背景下的中微子振荡

我们使用 eikonal 近似来计算两个中微子质量本征态在引力波或平面和 FRW 时空度量中的标量扰动的背景下传播期间它们之间的附加相移。我们评论了结果对扰动特征的依赖性，给出了一些数量级的估计，并发现尽管很小，但由此产生的相位差对于大红移仍然存在，直到我们的近似值有效。