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Even if it does affect it should affect all the surrounding object making it impossible to detect any change. It would be like keeping a man and a scale in a room, and if a gravitational wave is passed through them in a uniform pattern, the man would see no change in the scale as both shrink and expand at the same time.

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    $\begingroup$ 1) The GW isn't gravity so weights are not involved and scales are not pertinent in your example 2) no the man nor the scale shrink/expand as for their are kept together by electromagnetic forces ie the various chemical and electrical forces keeping their constituents together 3) light can detect the shrink/stretch of space via light time distance measurements like in giant interferometers (LIGO ...) or eventually as for its wavelength is shrinking and stretching. $\endgroup$ – Alchimista Jan 2 at 13:05
  • $\begingroup$ @Alchimista There is a place to submit answers for this question. You have put your answer in the comments section. $\endgroup$ – Aaron Stevens Jan 2 at 13:10
  • $\begingroup$ @Aaron Stevens I am not sure this deserve to be an answer. My knowledge of general relativity is not technical at all. I want to suggest what seems incorrect in the Q, or better in the assumptions that lead to the question. $\endgroup$ – Alchimista Jan 2 at 14:38
  • $\begingroup$ @Alchimista Comments are to ask clarifying questions or suggest improvements to how the question is written. Anything else should either be an answer or not posted at all. Stating where the OP is wrong in their reasoning can still be posted as an answer. $\endgroup$ – Aaron Stevens Jan 2 at 14:53
  • $\begingroup$ If you are referring to a specific experiment you should give a link $\endgroup$ – anna v Jan 2 at 19:34
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It would be like keeping a man and a scale in a room, and if a gravitational wave is passed through them in a uniform pattern, the man would see no change in the scale as both shrink and expand at the same time.

That exactly is why LIGO has two branches (not a scale, which is a single point of measurement). Distortions of space need two independent measurements.

ligo

Simplified operation of a gravitational wave observatory Figure 1: A beamsplitter (green line) splits coherent light (from the white box) into two beams which reflect off the mirrors (cyan oblongs); only one outgoing and reflected beam in each arm is shown, and separated for clarity. The reflected beams recombine and an interference pattern is detected (purple circle). Figure 2: A gravitational wave passing over the left arm (yellow) changes its length and thus the interference pattern.

If it crosses both at some other angle, the distances are so large that algebra can reconstruct the direction from the interference patterns

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  • $\begingroup$ but in this case why not just place a lazer carefully at the edge of a material such that when the a gravitaional wave passes, either end would allow the passing of the lazer. i hope you understood. $\endgroup$ – Athul Jeromy Jan 11 at 9:35
  • $\begingroup$ look at the space distortion that has to be detected so that it has the "signature" of a gravitational wave distortion. One dimension will not do it. en.wikipedia.org/wiki/Gravitational_wave#Effects_of_passing $\endgroup$ – anna v Jan 11 at 11:32
  • $\begingroup$ The effect is very very weak, that is why they use interference effects to see it at the maximum (90degrees) Also the direction of the wave is not known, and earth tides will also not cancel.. $\endgroup$ – anna v Jan 12 at 12:10

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