The universality of free fall, fundamental to metric theories of gravity, asserts the equality between inertial and gravitational mass, implying that all particles experience equal gravitational fall regardless of their mass. While it is widely accepted for all particles and photons, its applicability to neutrinos, due to their minimal interactions, remains uncertain. Neutrinos, though predicted to be massless, exhibit flavor-changing behavior and have nonzero mass, making it crucial to determine if they adhere to the principle. This paper introduces evidence from supernova 1987a observations suggesting that the time difference between correlated photons and neutrinos supports the universality of free fall for neutrinos with an accuracy of 2.7 part of a thousand.

中文翻译：

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中微子自由落体普遍性检验


自由落体的普遍性是引力度量理论的基础，它断言惯性质量和引力质量之间相等，这意味着所有粒子无论其质量如何，都会经历相同的引力下落。虽然它被广泛接受用于所有粒子和光子，但由于中微子之间的相互作用最小，它对中微子的适用性仍然不确定。尽管预计中微子是无质量的，但它却表现出改变味道的行为并且具有非零质量，因此确定它们是否遵循该原理至关重要。本文介绍了 1987a 超新星观测的证据，表明相关光子和中微子之间的时间差支持中微子自由落体的普遍性，精度为千分之 2.7。