>将来总有一天,一天的长度将超过86400原子秒。然后未来人类该怎么办?有一个时间标准,适用与提高物理和功能有一个时间标准,保持同步与地球自转与彼此格格不入。一个解决方案是继续做我们现在所做的。一天的长度已经超过86400原子秒。每隔一段时间(闰秒)(https://en.wikipedia.org/wiki/Leap_second)添加到保持时间以地球的旋转与时间以一个原子时钟同步。到目前为止,自1972年以来增加了37个闰秒。这一概念将继续工作,至少在未来几到几百年。最终,地球自转速度会放缓到了这样一种程度,闰秒的技巧将不再工作。>第二的定义会改变吗? Almost certainly. Scientists will eventually find something that is even better than is the unperturbed ground-state hyperfine transition frequency of the cesium-133 atom as a timekeeping device. That science advances is what science does. It has already been proposed to use pulsars rather than atomic clocks as a more precise timekeeping drive. One thing is certain: The second will not be redefined to be 1/86400 of a day.