Relativity of simultaneity and the balance of the systems

Click For Summary
SUMMARY

The discussion centers on the relativity of simultaneity and its implications for the ladder paradox in special relativity. Participants clarify that both the ladder and garage frames are non-inertial due to gravitational effects, which complicates the expected outcomes of simultaneity. The conversation emphasizes that simultaneity is frame-dependent and that the balance of systems must be analyzed within the context of their respective frames. Ultimately, the participants conclude that the ladder paradox cannot be fully understood without considering the non-inertial nature of the frames involved.

PREREQUISITES
  • Understanding of special relativity concepts, particularly the ladder paradox.
  • Knowledge of inertial and non-inertial reference frames.
  • Familiarity with the effects of gravity on frame dynamics.
  • Basic grasp of simultaneity and its implications in physics.
NEXT STEPS
  • Research the implications of non-inertial frames in special relativity.
  • Study the ladder paradox in detail, including its mathematical formulations.
  • Explore thought experiments related to simultaneity in different reference frames.
  • Investigate the effects of gravity on simultaneity and frame balance in relativistic contexts.
USEFUL FOR

Students of physics, particularly those studying relativity, educators explaining complex concepts, and researchers exploring the implications of simultaneity in non-inertial frames.

  • #61
russ_watters said:
Of course! Most of what happens in the universe doesn't happen here, we only observe it from here!

I don't see how - as long as you keep the reference frames straight and don't play loose with the wordings of the descriptions, it really is not difficult to interpret relativity of simultaneity. Most of your scenarios suffer from the same problem: you are wording them poorly which makes them tough to interpret. What bothers me is that you don't seem to care about getting them right (and are actually getting upset that people are trying to help you correct them! :confused: ) before jumping to the next poorly worded scenario.
Hi Russ,
Thank you for taking from your time to answer my comments.
Everything of what happens in the Universe has its cause in our frame of reference. We may not see the cause, but it is there, because there is no effect without cause.
I hope that you'll agree with this base law of Physics, without referring to theories.
As for now all theories must account for this law (Causality) - cause and effect.
The presented by me problem (I see it as such) is treating this exact matter.
To me, and according to causality, it is illogical to say that in our frame of reference we can have an effect without having the cause.
According to Special Relativity, whether two spatially separated events occur at the same time is not absolute, but depends on the observer's reference frame.
Which contradicts the law of cause and effect.
How? (explaining my understanding again)
In the ladder paradox thought experiment, if we set the simultaneously flapping doors to close an electrical circuit, thus powering an electrical lamp, we will have in the garage reference frame the cause (simultaneously closing doors) and the effect light from the electrical lamp.
In the ladder reference frame we will not have simultaneity, because it does pass through the garage, but will have the light from the electrical lamp.
So, the cause for the light in the ladder's reference frame is missing, because there is no simultaneity in the ladder reference frame (it passes through the garage), but the effect from the missing cause is present(!)
To me it is obvious that this is in a conflict with Causality (cause and effect)
If you now a way to satisfy the law of cause and effect in the above situation, please share.
 
Physics news on Phys.org
  • #62
Nugatory said:
Whereever in the rod the sound waves meet, it will be the same in all frames. See post 57 above.

Do remember, however, that the speed of the sound waves is different in different frames.

And the speed of sound waves with different directions is different in all frames except the medium frame.

So I suggest as a solution to the garage doors paradox that the anisotropy of the speed of sound in the garage doors cancels out the non-simultaneity of opening of the doors.
 
  • #63
Nugatory said:
You are misunderstanding what a frame is - a frame is no more than a convention for assigning coordinates to events. When I say that a chair is one meter to my left, and someone else says that the chair is two meters to the right of the table, we are using different frames. Thus, it makes no sense to say that something "lies in another frame", or is "in" this frame but not that one. Everything is always "in" all frames always, just as the chair is there no matter what numbers I use to describe its position.
:biggrin:
I understand very well what a reference frame is, and I should probably put quotes around that words, because all this conversation comes from my understanding that Special Relativity treats the reference frames as boxes, where in one box can "lie" simultaneity and in the other it will be missing.
Follow the conversation to get the context. See my previous comment.
And thank you for your time. I appreciate it :smile:
 
  • #64
Sisoeff said:
if we set the simultaneously flapping doors to close an electrical circuit, thus powering an electrical lamp, we will have in the garage reference frame the cause (simultaneously closing doors) and the effect light from the electrical lamp. In the ladder reference frame we will not have simultaneity, because it does pass through the garage, but will have the light from the electrical lamp.
This was addressed in post #45 already.
 
  • #65
A.T. said:
This was addressed in post #45 already.
Did you comment on it? I missed it.
My apologies, I'll find it now.
 
  • #66
Sisoeff said:
If you now a way to satisfy the law of cause and effect in the above situation, please share.
As with your other examples, you take into account the travel time of the signals - the electricity in this case. You will find that your system detects simulyaneity in one frame and non-simultaneity in all others. I think I've pointed this out three times now...
 
  • #67
Sisoeff said:
the cause for the light in the ladder's reference frame is missing, because there is no simultaneity in the ladder reference frame

You are not reading our responses. I have already said, multiple times now, that simultaneity is not a physical thing, and that you should not be focusing on it. And others have said that a "frame" is not a physical thing, it's just a way of labeling events, and events are "present" in all frames, they aren't "present" in some frames but not others.

Let me say the key points again, with emphasis: Simultaneity is not a physical thing. It is not a "cause" of anything. The true cause of the light going on in your scenario is not "simultaneity"; it's something else. And that something else is present in all frames, because all events are present in all frames.

Please read and re-read the above until it sinks in. Then go back over previous posts in this thread and find where we have told you, repeatedly, what the "something else" is that is the true cause of the light going on.

At this point I am closing this thread, because the root question has been answered repeatedly. Sisoeff, if you still have questions after doing what I suggest above, feel free to PM me.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
1K
  • · Replies 36 ·
2
Replies
36
Views
4K
  • · Replies 17 ·
Replies
17
Views
1K
  • · Replies 20 ·
Replies
20
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 116 ·
4
Replies
116
Views
9K
  • · Replies 221 ·
8
Replies
221
Views
15K
  • · Replies 21 ·
Replies
21
Views
2K
  • · Replies 33 ·
2
Replies
33
Views
3K