It has been suggested recently that the Hubble tension could be eliminated by a sharp, ∼10% increase of the effective gravitational constant at z∼0.01. This would decrease the luminosities of type 1a supernovae in just the needed amount to explain the larger value of the Hubble parameter. In the present paper we call attention to a dramatic effect of such transition on neutron stars. A neutron star that existed at z=0.01 would contract, conserving the baryon mass but undergoing a mass reduction. We computed neutron star models, with a realistic equation of state, and obtained that this reduction is typically 0.04M⊙. This amounts to an energy of 7×1052 erg. The transition will affect all neutron stars that formed along the history of each galaxy prior to the transition. Given the large number of neutron stars per galaxy, the liberated energy is huge. An estimate of the expected fluxes of neutrinos and x-rays yields values exceeding observational upper limits, thus rendering the late G transition scenario non-viable.

中文翻译：

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中子星对晚期 G 跃迁的约束


最近有人提出，哈勃张力可以通过在 z∼0.01 处将有效引力常数急剧增加约 10% 来消除。这将使 1a 型超新星的光度降低所需的量，以解释哈勃参数的较大值。在本文中，我们提请注意这种转变对中子星的巨大影响。存在于 z=0.01 处的中子星会收缩，重子质量守恒，但质量会减少。我们用一个真实的状态方程计算了中子星模型，并得到这个减少通常为 0.04M⊙。这相当于 7×1052 erg 的能量。这次转变将影响在转变之前沿着每个星系的历史形成的所有中子星。鉴于每个星系的中子星数量众多，释放的能量是巨大的。对中微子和 X 射线的预期通量的估计得出的值超过观测上限，因此使晚期 G 跃迁情景不可行。