# What do you think

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A question of curiosity

Does/can an infinity mirror (having two mirrors reflect each other) show/prove the finite speed of light?

So, if you use the highest resolution camera available to resolve the smallest microscopic reflected image possible within the infinite reflections and you wave your arm, would you see a delay from when you waved it to when the light image finally reaches our microscopic target?

By the way if this has already been done, I'm more interested in what you think would happen then in a link. I have no idea what would happen so I would like to brainstorm first before getting the link.

ps I'm writing 3 questions in different categories to brain storm on. If you have a link, please post what you think the answer is before you post link

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A question of curiosity

Does/can an infinity mirror (having two mirrors reflect each other) show/prove the finite speed of light?

So, if you use the highest resolution camera available to resolve the smallest microscopic reflected image possible within the infinite reflections and you wave your arm, would you see a delay from when you waved it to when the light image finally reaches our microscopic target?

By the way if this has already been done, I'm more interested in what you think would happen then in a link. I have no idea what would happen so I would like to brainstorm first before getting the link.

ps I'm writing 3 questions in different categories to brain storm on. If you have a link, please post what you think the answer is before you post link

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A question of curiosity

Does/can an infinity mirror (having two mirrors reflect each other) show/prove the finite speed of light?

So, if you use the highest resolution camera available to resolve the smallest microscopic reflected image possible within the infinite reflections and you wave your arm, would you see a delay from when you waved it to when the light image finally reaches our microscopic target?

By the way if this has already been done, I'm more interested in what you think would happen then in a link. I have no idea what would happen so I would like to brainstorm first before getting the link.

ps I'm writing 3 questions in different categories to brain storm on. If you have a link, please post what you think the answer is before you post link

First thought (thinking while reading): There would have to be so many reflections to observe a measurable delay the image you were looking at microscopically would be so small it would instantly jump out of view at the slightest movement.

Second thought: Put the mirrors a long way apart. Perhaps one of them on the moon. The delay is easily measured on a single reflection proving the speed of light is finite.

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A question of curiosity

Does/can an infinity mirror (having two mirrors reflect each other) show/prove the finite speed of light?

So, if you use the highest resolution camera available to resolve the smallest microscopic reflected image possible within the infinite reflections and you wave your arm, would you see a delay from when you waved it to when the light image finally reaches our microscopic target?

By the way if this has already been done, I'm more interested in what you think would happen then in a link. I have no idea what would happen so I would like to brainstorm first before getting the link.

ps I'm writing 3 questions in different categories to brain storm on. If you have a link, please post what you think the answer is before you post link

First thought (thinking while reading): There would have to be so many reflections to observe a measurable delay the image you were looking at microscopically would be so small it would instantly jump out of view at the slightest movement.

Second thought: Put the mirrors a long way apart. Perhaps one of them on the moon. The delay is easily measured on a single reflection proving the speed of light is finite.

Proving the need for proof is much more difficult.

--Brant

way beyond me

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when I specifically said to provide discussion before links!

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Second thought: Put the mirrors a long way apart. Perhaps one of them on the moon. The delay is easily measured on a single reflection proving the speed of light is finite.

Honestly I wasn't looking for the proof of the finite speed of light, more that I wanted to see if we can see such and effect using such a method. But yes I would have spaced the mirrors but not by that much (maybe 10 feet, using 10-20 foot square mirrors) because Im looking for that specific back and forth reflecting effect

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Second thought: Put the mirrors a long way apart. Perhaps one of them on the moon. The delay is easily measured on a single reflection proving the speed of light is finite.

Honestly I wasn't looking for the proof of the finite speed of light, more that I wanted to see if we can see such and effect using such a method. But yes I would have spaced the mirrors but not by that much (maybe 10 feet, using 10-20 foot square mirrors) because Im looking for that specific back and forth reflecting effect

Are you thinking about a way to design an experiment you can do at home? Measuring the propagation time through a transmission line (near the speed of light) is fairly easy to do. An electronics experiment using a light source and detector and oscilloscope and varying the distance between the source and detector is a fairly cheap experiment anyone could do. This wouldn't measure the speed of light through a vacuum but through the air is pretty close. Cable guys troubleshoot their cables using time domain reflectometry (TDR) which is calculating the distance to a discontinuity by measuring the time delay of a reflected signal. Knowing the propagation speed of the cable you can calculate the distance.

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I see, you simply want to see the delay, not to measure it. The processing time of the rods and cones of the eye to the brain is somewhere around 30mS. Light travels around 100Km in that time. That is a lot of reflections between two mirrors spaced 10 feet (3 meters) apart. The final image would be very very small. The mirrors would have to be perfect, 100% reflective with no losses. I don't think what you ask for is possible except as a thought experiment. I've been trying to do what you asked, think it out without clicking links.

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I see, you simply want to see the delay, not to measure it. The processing time of the rods and cones of the eye to the brain is somewhere around 30mS. Light travels around 100Km in that time. That is a lot of reflections between two mirrors spaced 10 feet (3 meters) apart. The final image would be very very small. The mirrors would have to be perfect, 100% reflective with no losses. I don't think what you ask for is possible except as a thought experiment. I've been trying to do what you asked, think it out without clicking links.

Thanks Mikee, for seeing that the point is not to measure the speed, and thanks for your participation. The point about the mirrors being perfect is s good point as the camera would be examining a almost point like image that with any mirror distortion would be far from clear. I feel like today's camera could resolve such a small image though but the internal distortion could be a problem..... so you use liquid mercury, one on the ground and another suspended above.

Light moves 1 foot per nanosecond and we put the mirrors 100 feet apart (30 foot square mercury mirrors, up in the alps for less atmospheric interference) The in 1 second the light would reflect 10 million times which would be 5 million images on each mirror. I wish I had some quick software to show what that would look like-- maybe some time lapse video that takes us through the images showing just how small this final image would be....

But then the question is, would that 5 millionth image be distant enough away that the delay would be more then what we could see anyway based on your information about human perception time