How to correctly mark event B on the picture?

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This discussion centers on the correct identification of event B in a thought experiment involving a photon clock moving at velocity V. The participants clarify that event B is located at the middle of the left-bottom mirror in the second frame, where the clock is at rest. The Principle of Relativity is emphasized, indicating that both frames (moving and stationary) are reversible and that event A occurs directly above event B in both scenarios. The mathematical relationship between the events is expressed through the equation $$c^2\Delta t^2-\Delta x^2 = c^2\Delta t_0^2-\Delta x'^2$$.

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Mike_bb
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Hello!

I have photon clock that moves to right side with velocity V.
In the first case events A and B are depicted on the picture on the top side:

1.jpg


In accordance with the Principle of Relativity I obtained second case.
But I can't mark event B in the second case on the bottom side. Where is event B located in this case?

Thanks!
 
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I guess you describe the same events A and B from the viewpoint of two different frames: In the first frame (upper image), the light clock moves to the right, in the second frame (lower image) it moves to the left. If that's the case, then event B on the lower image is located in the middle of the left-bottom mirror where it meets the arrow.
 
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It's difficult to know because you haven't described the experiment clearly. @Histspec's guess is reasonable and may be correct, but it's a guess.

You say the clock is moving to the right. Presumably that's in the top picture. Is it supposed to be moving to the left in the lower picture? That's what I would guess, but that's an unusual thing to do with a light clock since it doesn't really gain you anything. What's the extra quantity ##t_0## in the srcond diagram? How does it relate to anything else? Is the shading of the mirrors meant to be indicative of something? And what are events A and B supposed to be?

In particular, if you write down a description of A and B I suspect you will answer your own question.
 
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Ibix said:
It's difficult to know because you haven't described the experiment clearly. @Histspec's guess is reasonable and may be correct, but it's a guess.

You say the clock is moving to the right. Presumably that's in the top picture. Is it supposed to be moving to the left in the lower picture? That's what I would guess, but that's an unusual thing to do with a light clock since it doesn't really gain you anything. What's the extra quantity ##t_0## in the srcond diagram? How does it relate to anything else? Is the shading of the mirrors meant to be indicative of something? And what are events A and B supposed to be?

In particular, if you write down a description of A and B I suspect you will answer your own question.
In the top picture clock is moving to right. But in the lower picture clock is rest. (In accordance with Principle of Relativity)

$$c^2\Delta t^2-\Delta x^2 = c^2\Delta t_0^2-\Delta x'^2$$
 
Mike_bb said:
In the top picture clock is moving to right. But in the lower picture clock is rest.
Then, in the second picture there is no velocity ##v## and no moving clock. Event A occurs directly above event B.
 
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PeroK said:
Then, in the second picture there is no velocity ##v## and no moving clock. Event A occurs directly above event B.
These equality for first and second picture:

$$c^2\Delta t^2-\Delta x^2 = c^2\Delta t_0^2-\Delta x'^2$$
$$c^2\Delta t_0^2-\Delta x'^2 = c^2\Delta t^2-\Delta x^2$$

In accordance with Principle of Relativity we have that first frame and second frame are reversable. It's shown on the first and second picture.
 
PeroK said:
Event A occurs directly above event B.
Thanks. It's right!
 

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