Imagine that there is a cube box that has mirrors all 6 faces in . If we use a strong laser and enter in the box from a small hole on the box. The laser light travels in the box long time that we can detect the laser via a detector on other hole of the box.

1) Is it possible to simulate the long light travel in it (for example a day or week)? 2) Is it possible to proof that there is no ether via that box? If we move the box in a fixed velocity what we can observe about receive time on detector.

I ask a question first time in this website If it is asked question or not appropriate for your format sorry for that.

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    $\begingroup$ possible duplicate of What longest time ever was achieved at holding light in a closed volume? $\endgroup$
    – Qmechanic
    Mar 9, 2012 at 12:25
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    $\begingroup$ Thanks for the link. The other question is about half part of my question. I also wonder my second question's answer that need to understand theoretical way about such mirror box. If possible to create such mirror box with advanced technology in future time what we can observe. My question is related to special relativity case. $\endgroup$
    – Mathlover
    Mar 9, 2012 at 12:42
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    $\begingroup$ The michelson morley experiment (which tried to detect the luniniferous aether) used multiple reflections. No need for a box; just some well-aligned mirrors and beam splitters. $\endgroup$ Mar 9, 2012 at 12:47
  • $\begingroup$ I don't mention to measure the speed of box via speed of light. I mention the receive time to detector. Can it change via fixed velocity or same time? $\endgroup$
    – Mathlover
    Mar 9, 2012 at 12:52

1 Answer 1


1) In theory, yes. In practice, some of the light is absorbed and some is scattered every time it bounces off a mirror, so I think that keeping it bouncing around for anything like a day would be next to impossible to achieve.

2) Yes. If the box is moving with a fixed velocity we will observe no difference in the receive time, as long as the clock used to measure it is moving along with the box at the same speed. As Manishearth commented, this is essentially what the Michelson-Morley experiment measured. Special relativity tells us that there is no experiment we can do that will give us different results if it's moving at a constant velocity, and this experiment is no different from any other in this respect. In special relativity you will always measure the speed of light to be the same constant, no matter how fast you're moving.


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