标题： 相对论收缩及相关效应在非惯性系中 显示英文标题

标题： Relativistic contraction and related effects in noninertial frames

摘要： 尽管旋转圆盘上不同点之间没有相对运动，但每个点都属于不同的非惯性系。 这一事实之前在处理埃伦费斯特悖论及相关问题的方法中未被认识到，现在被用来对旋转环和旋转圆盘进行正确的处理。 恢复了张力应力，但与标准方法的预测相反，发现圆盘边缘的观察者会看到其他不同运动物体的长度与瞬时位置和速度与该观察者相同的惯性观察者所看到的长度相等。 还讨论了不同位置的钟的速率，以及由不同观察者所看到的情况。 一些结果被推广到在平坦或弯曲时空中的任意运动观察者。 在非时间正交框架中普遍接受的空间线元公式在某些情况下是不合适的。 使用费米坐标得出的结果是，对于任何观察者，光速都是各向同性的，并且等于$c$，前提是通过在观察者附近的小区域内传播光束来测量它。 显示英文摘要

摘要： Although there is no relative motion among different points on a rotating disc, each point belongs to a different noninertial frame. This fact, not recognized in previous approaches to the Ehrenfest paradox and related problems, is exploited to give a correct treatment of a rotating ring and a rotating disc. Tensile stresses are recovered, but, contrary to the prediction of the standard approach, it is found that an observer on the rim of the disc will see equal lengths of other differently moving objects as an inertial observer whose instantaneous position and velocity are equal to that of the observer on the rim. The rate of clocks at various positions, as seen by various observers, is also discussed. Some results are generalized for observers arbitrarily moving in a flat or a curved spacetime. The generally accepted formula for the space line element in a non-time-orthogonal frame is found inappropriate in some cases. Use of Fermi coordinates leads to the result that for any observer the velocity of light is isotropic and is equal to $c$, providing that it is measured by propagating a light beam in a small neighborhood of the observer.