Brain Teaser: Classical Simultaneity

脑筋急转弯：经典同时性

The next brain teaser is meant to challengeyour understanding of the previous lessons. It reaches an erroneous conclusionbecause one of the assumptions is wrong.

下一个脑筋急转弯是要挑战你对先前课程的理解。由于一个假设是错误的，它得出了一个错误的结论。            

Classical Simultaneity

 经典的同时

In the previous video we have shown thattwo events simultaneous in a rest frame are not simultaneous in a moving frame.We have used the thought experiment of a moving train and of two flashes oflight that go off at the front and the end of the train. What would change ifinstead of light, we would be dealing with sound?

在前面的视频中，我们展示了在静止帧中同时发生的两个事件在移动帧中不是同时发生的。我们使用了一个移动列车的思想实验，以及在列车前部和终点发出的两道闪光。如果光不是光，我们会改变什么？

On the surface, the same reasoning shouldapply:

表面上，同样的道理应该适用：

Let's assume two explosions simultaneous inthe station frame take place at the front and the end of the train. By the timethe sound from the explosion at the front of the train reaches an observer atthe middle of the train, the noise from the explosion at the back of the trainstill needs to cover the extra-distance over which the train has movedmeanwhile. Because the sounds from the two explosions do not reach the observerat the middle of the train at the same time, the observer would conclude thatthe two explosions are not simultaneous.

让我们假设火车站的两个爆炸同时发生在火车的前部和终点。当火车前部的爆炸声到达火车中间的观察者时，火车后部爆炸的声音仍然需要覆盖列车移动的额外距离。因为两次爆炸的声音并没有到达火车站中间的观察者。 

It would seem that even in classicalmechanics, two events simultaneous in a rest frame are not simultaneous in amoving frame. What went wrong?

即使在经典力学中，静止帧中同时发生的两个事件也不是。动帧同步。出了什么问题吗？              时间，观察者会断定这两次爆炸不是同时发生的。