标题： 从非共形耦合的精细结构常数变化 显示英文标题

标题： The variation of the fine-structure constant from disformal couplings

摘要： 我们研究了一种理论，在这种理论中，电磁场不仅与标量场有通常的非最小耦合，还与标量场有不合标准的耦合。 我们证明，不合标准的耦合会修改精细结构常数 α 的表达式。 因此，我们所考虑的理论可以通过单纯考虑不合标准的耦合来解释 α 的非零报告变化。 我们还发现，如果物质和光子以相同的方式与标量场耦合，则不合标准的耦合本身不会导致精细结构常数的变化。 讨论了一些与当前天体物理、地球化学、实验室和宇宙微波背景辐射对 α 宇宙学演化限制一致的情景。 所提出的模型也与当前对有效暗能量方程状态的 Ia 型超新星限制一致。 我们发现，特别是奥库洛界的约束对模型参数施加了强烈的限制。 从我们的数值结果来看，我们发现引入非最小电磁耦合增强了 α 的宇宙演化。 预计 ALMA 和新一代高分辨率超高精度光谱仪（如 PEPSI、ESPRESSO 和 ELT-HIRES）将报告更好的限制数据。 此外，分子钟和核钟灵敏度的预期提高将对当前实验室测量施加更严格的限制。 显示英文摘要

摘要： We study a theory in which the electromagnetic field is disformally coupled to a scalar field, in addition to a usual non-minimal electromagnetic coupling. We show that disformal couplings modify the expression for the fine-structure constant, alpha. As a result, the theory we consider can explain the non-zero reported variation in the evolution of alpha by purely considering disformal couplings. We also find that if matter and photons are coupled in the same way to the scalar field, disformal couplings itself do not lead to a variation of the fine-structure constant. A number of scenarios are discussed consistent with the current astrophysical, geochemical, laboratory and the cosmic microwave background radiation constraints on the cosmological evolution of alpha. The models presented are also consistent with the current type Ia supernovae constraints on the effective dark energy equation of state. We find that the Oklo bound in particular puts strong constraints on the model parameters. From our numerical results, we find that the introduction of a non-minimal electromagnetic coupling enhances the cosmological variation in alpha. Better constrained data is expected to be reported by ALMA and with the forthcoming generation of high-resolution ultra-stable spectrographs such as PEPSI, ESPRESSO, and ELT-HIRES. Furthermore, an expected increase in the sensitivity of molecular and nuclear clocks will put a more stringent constraint on current laboratory measurements.