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@tangolin I have edited my question. I would suggest your teacher does the same to their question. š I am not surprised you were confused by this. It took me to start diagramming it myself to realise that the question is really badly worded.
Not a problem. Iām going to try that also. Iād suggest drawing rays of light from the person to both edges of the pool and at regular intervals (every 20cm) across the pool. To start with. And refract all of them.
I think itās not necessary that the circle of light seen by the person is exactly centred on the source of light like it is in your diagram. The circle of light seen by the person will be offset towards the person. The farthest part of the circle seen by the person will actually be in between the source of light and the user.
As an interesting and semi-relevant link here is an example of what can happen when the liquid in the container is incredibly viscous and DOES rotate when the container rotates... youtu.be/j2_dJY_mIys
@Albert I believe what is being said is that the ruler measures the distance between two points in space just as the metronome measures the ādistanceā between points in time. If you set off a metronome at one tick per second and then move it at close to C then the ticking with slow down. Just as the ruler will contract. But when you bring it back to relative resting it will still be ticking at 1 tick per second. Whereas the clock in the paradox is measuring the time interval from leaving to returning. Just as the odometer is measuring the perceived distance travelled from leaving to returning.
@Nathaniel how do you send the timing to each part of the stack? Given that we're talking in astronomical distances does "precise timing" over those scales even have a meaning? It can be proven that in certain circumstances the order of events and so "precise timing" doesn't mean things happen in the same order for everyone.
There is also the fact that information is also the information of the fact that you are moving the paper. So no matter how long it took you to āfoldā your end of the stack, that information will only propagate at a speed < c to the rest of the stack that would slowly catch up.
Just to add... Are the train tracks in that picture parallel? If you answer yes then how can that be possible to make lines that are not parallel in the photo? (Same answer as for the sun beams).
