Light-clock and time dilation [was: Hydrogen atom expressed mathematically]

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Key issue - I am talking about just a single photon and where it eventually hits. Target one or target two? Can't be both unless we are talking two photons, in which case we are measuring two different paths of different lengths.
 
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PeroK said:
I'm sorry if that is your attitude. You'll need to find someone else to waste their valuable time trying to teach you something you don't really want to learn.

Your misapprehensions about this experiment are actually quite common. You shouldn't mistake beginner's errors for insights that a hundred years of professional physicists have missed.


Somebody missed something. Which target? 1 or 2?
 
erik giles said:
Somebody missed something. Which target? 1 or 2?
Depends on your setup - I think you intend it to hit the blue target, but I'm not completely clear on your setup. Both frames will agree, whichever it is. Google relativistic aberration.
 
Ibix said:
You may wish to look up "relativistic aberration", which is the phenomenon you are denying occurs.

I am not denying anything. I am asking which target? Can anyone answer?

I know all these concepts and I know the concepts are correct.

The only incorrect thing here is the light clock thought experiment, which I have proven invalid. Can anyone prove it valid?

This experiment works, with matter, but not light.
upload_2017-11-26_13-51-5.png
 

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If it hits target 2, then the path is different (and longer) as the photon went at another angle, unless we believe the photon hits both targets.

I do know that the moving target also experiences time dilation so it would observe the photon hitting target one at a different time.
 
Ibix said:
Your diagram seems to be denying it...

Is the path to target two longer or shorter (or the same)
erik giles said:
I am not denying anything. I am asking which target? Can anyone answer?

I know all these concepts and I know the concepts are correct.

The only incorrect thing here is the light clock thought experiment, which I have proven invalid. Can anyone prove it valid?

This experiment works, with matter, but not light.View attachment 215666

than the path to target one?

Does a photon aimed straight up (relative to target one) deflect to follow and strike target one? Actually, yes I am denying the validity of the light clock thought experiment.
 
Let's analyse this carefully. Don't worry about any movement for a minute. In a frame in which your setup is not moving, which target do you expect to be hit?
 
erik giles said:
Target 1.
Actually, in a non-moving experiment, both targets.
 
erik giles said:
Target 1.
OK. Now will it hit or miss that target when the setup is moving?

Note that any other answer than "it hits the same target" implies that an observer inside the rig can detect whether or not the rig is moving without referring to anything outside it. That is, you imply the existence of absolute motion, and deny the principle of relativity.
 
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erik giles said:
Target 1.
If you aim your emitter (laser pointer) at right angle in the emitter's frame, this light pulse will always have the same x - velocity as the emitter. In this case the target and the emitter are always at points of closest approach, or right opposite.
If you wish to hit a target which was at point of closest approach at the moment of emission, you must aim your emitter (laser pointer) backward at relativistic aberration angle ##\sin \alpha = v/c##
This video in the youtube shows path of light pulse in different frames.

 
Ibix said:
OK. Now will it hit or miss that target when the setup is moving?

Note that any other answer than "it hits the same target" implies that I can detect whether or not the rig is moving without referring to anything outside it. That is, you imply the existence of absolute motion, and deny the principle of relativity.

If target one moves perpendicular to the source beginning at T-0 at 0.87C, while target two remains stationary, and both targets are 15 light seconds from the emitter at T-0, what target does it hit at T+15 seconds?

Any answer other than target two implies that we have violated the principle of matter occupying more than one place at the same time.

I am going to write a paper on this and ask you all to peer review it if you don't mind. My point is, the light clock thought experiment is invalid. Relativity is valid.

Thanks!
 
Bartolomeo said:
If you aim your emitter (laser pointer) at right angle in the emitter's frame, this light pulse will always have the same x - velocity as the emitter. In this case the target and the emitter are always at points of closest approach, or right opposite.
If you wish to hit a target which was at point of closest approach at the moment of emission, you must aim your emitter (laser pointer) backward at relativistic aberration angle ##\sin \alpha = v/c##
This video in the youtube shows path of light pulse in different frames.



Agreed. Now in this case, the light photon is actually traveling the hypotenuse and will hit the moving target. The observer traveling parallel to it will experience time dilation such that from his view, light remains constant velocity C and gives the appearance of 'straight up' movement within his reference frame.

Therefore the light traveled at the angle and hits target one. Light projected 'straight up' from the vantage point of the emitter, and per this point of view, will deflect and hit target two. Thus the emission angle makes the difference.
 
erik giles said:
If target one moves perpendicular to the source beginning at T-0 at 0.87C, while target two remains stationary, and both targets are 15 light seconds from the emitter at T-0, what target does it hit at T+15 seconds?
We've answered this already. Actually, according to your green observer, the pulse hits nothing at T+15 - it's still in flight (towards target 1). According to an observer on the rig it hits target 1 at that time (they have different notions of what "fifteen seconds later" means).
erik giles said:
Any answer other than target two implies that we have violated the principle of matter occupying more than one place at the same time.
I've no idea why you think that. The light strikes target 1 and only target 1. I think you need to read up on relativistic aberration, since that explains why target 1 is hit from the perspective of your green observer.
erik giles said:
I am going to write a paper on this and ask you all to peer review it if you don't mind.
Since what you are describing is inconsistent with relativity, you may wish to review the rules on personal theories before doing so.
erik giles said:
My point is, the light clock thought experiment is invalid. Relativity is valid.
Those two sentences contradict one another.
 
erik giles said:
I am going to write a paper on this and ask you all to peer review it if you don't mind.

We don't do peer review here. That's not what PF is for. You would need to submit your paper to an actual scientific journal that does peer review. I doubt any journal would accept it since you have a number of obvious misconceptions, but you could try.

erik giles said:
My point is, the light clock thought experiment is invalid. Relativity is valid.

As far as I (or everyone else posting in this thread) can see, your understanding is what is invalid. We've done our best to try to help you, but you are not listening. Therefore, this thread is closed.
 
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