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# A thought experiment about light

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Posted (edited)

If I understand what you are saying, and it's a bit (if) here. It depends on your frame of reference. Take the light emitted from two sources inside a ship. The person inside the ship measures the light signal normally, moving in a vertical motion from the first detector and emitter to the second detector which in turn, emits it again. But someone outside the ship measuring the light, does not see the light signal moving in a horizontal motion. They will see it move with a slight shift causing it to move in a zig zag motion. This was in fact Einsteins first realization about how the light click in the moving frame of reference must take a little bit more time to traverse than the clock emitted in a stationary motion indicating that time had slowed down on the ship. In regards to your question... "if" I understand what you are roughly saying, is actually a frame-dependant thing. Give me a different example of your thought experiment where you have someone traveling with the apparatus to someone measuring it from a stationary frame then tell me what your result or conclusions are from it.

Edited by Dubbelosix
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First of all, does light have inertia? The most simplest of model would say yes. In fact many books and scientists will tell you it has a mass. This is because it's energy has units of mass so we writ

I never witnessed any experimental evidence personally. So I doubt everything. I believe in photons because I think photon is the lowest unit of light. Light must be composed of something, and it

18 minutes ago, Dubbelosix said:

Give me a different example of your thought experiment where you have someone traveling with the apparatus to someone measuring it from a stationary frame then tell me what your result or conclusions are from it.

If observer_1 saw the light hit point A on mirror 1, them  observer_2 would see the light hit point A on mirror 1 as well.

In my experiment, the mirrors, light source, earth and observer are all in a same frame. What I am curious about is the direction of the light.

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Posted (edited)

If you have two observers seeing a light hitting a single place on a mirror, it is not exactly the same way on (a point) of a mirror. Because, if we rotate a point you don't get back the same orientation in a 360 degree turn, the only way to do it, is by rotating it 720 degrees, I think. So in the end your thought experiment is interesting, because the rotations laws just are preserved in point approximated dynamics for particle. A detector and the detectee are inherently coupled in any physics model, so the rotation of the mirror should preserve these strange laws. We'll done, im impressed!

Edited by Dubbelosix
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I would like to add though. The Idea holds only if a particle is truly pointlike.

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10 hours ago, Dubbelosix said:

Go away, I never said they were the same thing, you're looking more foolish than you ever did. In fact I'm saying the complete opposite, I'm saying mass and matter is not the same thing. Besides, I provided not just a textbook quote, but even an online quote which clearly demonstrates that there is more to the notion that a photon has a measure of mass but not matter. See you don't like being corrected?

Put me on a vacation all you want, I dont act kindly to idol threats, Ocean. If you even dare I'll never return. Either way, I would care. I'm in the middle of some serious chess training so it's not as if come here because im bored. I come here to help people understand science. You're just like trump sitting behind a nuclear button and it gives you some kind of cheap thrill. If others learn from me. Then that's a good thing, but don't start waving your fist about because you didn't lime being told off in a subject you are poorly educated on. That's not my fault.

OK, I am giving you a couple of weeks off and if you decide not to return that is entirely up to you. Most people here probably don't know that you have been kicked off of almost every physics forum that exists on the Internet and return using sock puppets. I am giving you a vacation because 1) you are posting BS about light having mass and using an equation that only applies to particles with mass. 2) Being insulting not only to me, but to others as well. Go post somewhere else where you are not already banned, if such a place exists.

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Simon;

In making any device, there is never any concern regarding motion of the Earth surface or Earth motion in space. If you build a light clock (your primitive device) in the summer time, it continues to work even though Earth is constantly changing direction. So from experience, processes work the same in any ref. frame that is moving at a uniform velocity (constant speed, constant direction), which is postulate 1 in SR. The curvature of Earth orbit is not a significant factor for processes with short cycles.

Your device works independently of direction/orientation.

If aberration is a concern, that requires a telescope to be aligned off center from the light source because the viewer has no control over the direction of propagation. How does light move in the correct direction to intercept the mirror?There was no answer until Richard Feynman published '"QED", a theory of light.The short answer is, light moves wherever it can, and a small portion reaches the target.

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9 hours ago, sluggo said:

Your device works independently of direction/orientation.

Can I interpret your answer as "after the rotation, the light does not change"?

Is the device of Michelson-Morley independently of direction as well?

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Simon;

Quote

Can I interpret your answer as "after the rotation, the light does not change"?

[Yes. If experiments involving light transmission didn't work because of issues with direction, it would have been discovered long ago. I'm giving a logical explanation since you are hesitant to trust an answer based on theory.

R. Feynman's "QED" with its experimental verification, supports the photon model of light (vs the wave model), and explains most light phenomena, reflection, diffraction, etc. very accurately.

Go [here] for a list of experimental verification (facts) of SR.]

Quote

Is the device of Michelson-Morley independently of direction as well?

[If the MM experiment is considered a two clock experiment, one with vertical oscillation, the other with horizontal oscillation, then the same reasoning can be applied. A working light clock should not stop working by rotating it 90°. Be aware of additional factors such as length contraction which is the explanation for the null results.]

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