We thoroughly examine the role of absolute and relative simultaneity in the interpretation of the Sagnac effect, using an approach that allows for determining the local speed along the light path. If the local speed of light is assumed to be c over the whole closed contour, there is no agreement with the observed result. There is agreement if the local speed is c along an open section of the contour only. Thus a rigorous and coherent interpretation of the Sagnac effect favours absolute over relative simultaneity. The implications for the Lorentz transformations and synchronization by means of the Global Positioning System are considered.

中文翻译：

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Sagnac效应和同时性在相对论中的作用

我们使用允许确定沿光路的局部速度的方法，彻底检查了绝对和相对同时性在解释Sagnac效应中的作用。如果假定局部光速在整个闭合轮廓上为c，则与观察到的结果不一致。如果局部速度仅沿轮廓的开放部分为c，则存在一致。因此，对萨格纳克效应的严格和连贯的解释倾向于绝对绝对而不是相对同时性。考虑了通过全球定位系统进行的洛伦兹变换和同步的意义。