WIKI and Time Dilation: The Possible Error in Relative Velocity

In summary, the conversation is discussing the concept of time dilation due to relative velocity, specifically in the context of the Lorentz-Fitzgerald formula. There is some disagreement about the use of the formula and whether it is appropriate to use it in certain cases. The conversation also touches on the concept of the "rest frame" and how it is defined.
  • #281
chinglu1998 said:
Fine, I'm done. I showed you at least three times where I wanted to look at the calculation from the view of the clock frame.
And I never denied that you "wanted to look at the calculation from the view of the clock frame", smartass (I already mentioned this in my previous post when I said I never denied that you wanted to calculate something "from the clock frame", I just pointed out you had changed your story about whether the observer was moving or stationary relative to the clock frame). I just responded to your statement that you wanted the observer and the clock to be the same frame, then you accused me of mistakes and errors even though that was exactly what you just said.
chinglu1998 said:
Then, you continue to call me a liar even after I have provided evidence in a thread you are supposed to be reading.
Provided evidence of what? All you provided evidence for was that you had said you wanted to calculate things "from the clock frame", but this was irrelevant because I never said anything different. I guess you want to continue to avoid the issue I actually raised, namely that you had changed your notion of whether the observer was at rest or moving relative to the clock.
chinglu1998 said:
I do not want to be at a place where I have answered truthfully, provided evidence of what I said and am still called names by someone out of anger.
You certainly never "answered truthfully" about whether you had changed your story about whether the observer was moving or stationary relative to the clock, you seem to be doing everything possible to change the subject and avoid addressing this topic. Anyway, if finding new ways to avoid answering simple questions is getting tiring for you so you want to leave the thread instead, don't let the door hit your *** on the way out!
 
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  • #282
chinglu1998 said:
Can we show with with the light aberration argument of WIKI?
If you had a light clock at rest in the primed frame, then yes, otherwise no (how could you measure the light aberration of a clock that doesn't exist?). (Note that this has no bearing on the applicability of Lorentz transforms as all that is needed is the relative velocity to transform from the coordinates of events in a given frame to their coordinates in another.)
 
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  • #283
JesseM said:
And I never denied that you "wanted to look at the calculation from the view of the clock frame", smartass (I already mentioned this in my previous post when I said I never denied that you wanted to calculate something "from the clock frame", I just pointed out you had changed your story about whether the observer was moving or stationary relative to the clock frame). I just responded to your statement that you wanted the observer and the clock to be the same frame, then you accused me of mistakes and errors even though that was exactly what you just said.

Provided evidence of what? All you provided evidence for was that you had said you wanted to calculate things "from the clock frame", but this was irrelevant because I never said anything different. I guess you want to continue to avoid the issue I actually raised, namely that you had changed your notion of whether the observer was at rest or moving relative to the clock.

You certainly never "answered truthfully" about whether you had changed your story about whether the observer was moving or stationary relative to the clock, you seem to be doing everything possible to change the subject and avoid addressing this topic. Anyway, if finding new ways to avoid answering simple questions is getting tiring for you so you want to leave the thread instead, don't let the door hit your *** on the way out!

I am sorry I did not handle your extreme emotion better.

I thought this is a debate with emotion.

I started out the thread that the article was wrong.

In my view it is. Others claimed the moving observer is not actually moving by at rest or something or whatever.

Many posts went in this direction.

So, I said fine, both cannot be correct. So, I made a change of direction and decided to view the clock frame as stationary since that is what I thought in the first place.

Now, you clearly understood how to calculate from the moving observer, but when I switched to the clock as the frame, you have expressed all this anger and hostility.

So, that was my thought process.

Now, are you going to calculate the time dilation with light aberration from the clock frame as the frame or no.
 
  • #284
chinglu1998 said:
So, I said fine, both cannot be correct. So, I made a change of direction and decided to view the clock frame as stationary since that is what I thought in the first place.
I'm not talking about which frame is "moving" or "stationary" because those are just arbitrary labels which have nothing to do with calculating anything. I'm asking whether you acknowledge that you changed your scenario, first saying the observer was at rest relative to the clock and then accusing me of an error when I discussed what would be true if the observer was at rest relative to the clock. This is a simple question, can you stop changing the subject and address it?
chinglu1998 said:
Now, are you going to calculate the time dilation with light aberration from the clock frame as the frame or no.
Not if you won't address the very simple question above, and also not if I can't understand what you are asking me to calculate. The time dilation involves the time intervals in two frames, what does it mean to calculate the time interval in the observer's frame "from the clock frame"? That seems like a meaningless request. It might help if you'd address the end of post #277 where I pointed out that the wiki article clearly uses both frames, using the clock frame to find the time interval in the clock frame, and the observer's frame to find the time interval in the observer's frame.
 
  • #285
chinglu1998 said:
Fine, I'm done. I showed you at least three times where I wanted to look at the calculation from the view of the clock frame. There are many more. Then, you continue to call me a liar even after I have provided evidence in a thread you are supposed to be reading.

you continue to ask for what happens from the clocks frame, people have answered many many times that from the clocks frame the clock isn't dilated. Obviously the clock is going to tick at the normal rate in it's own frame since in that frame the clock isn't moving.

Do you want to know the time dilation in the observer's frame when looked at from the clock's frame of reference?

This is NOT the same thing as asking the clock's rate when it's at rest wrt the observer.
 
  • #286
IsometricPion said:
If you had a light clock at rest in the primed frame, then yes, otherwise no (how could you measure the light aberration of a clock that doesn't exist?). (Note that this has no bearing on the applicability of Lorentz transforms as all that is needed is the relative velocity to transform from events in a given frame to their coordinates in another.)

I could ask you how does the observer that is moving in the WIKI artricle has any time.

Here is the calculation.

Assume the clock and light source are at reat. Let d be some mark on the y-axis of the clock frame. Then, it will t = d/c.

Now, in a frame in relative motion to the clock, it will see light aberration in the view of the clock frame since it is moving and the light is traveling in straight lines in the clock frame, they must travel at an angle in the moving frame.
Hence, c²t²' = (vt')² + c²t²

√ (c²t²' - v²t'²)/c = t²
t'√ (c² - v²)/c = t²

So, t'/γ = t.

The primed frame is the moving frame.
 
  • #287
chinglu1998 said:
I am sorry I did not handle your extreme emotion better.

I thought this is a debate with emotion.

I started out the thread that the article was wrong.

In my view it is. Others claimed the moving observer is not actually moving by at rest or something or whatever.

That is exactly what the article says we are calculating from the observer's frame of reference the observer is moving at velocity v with respect to the clock. So when you calculate from the "moving observer's" frame of reference it is at rest in that frame of reference.

Many posts went in this direction.

So, I said fine, both cannot be correct. So, I made a change of direction and decided to view the clock frame as stationary since that is what I thought in the first place.

The clock's frame is only at rest in it's own frame of reference. In the observer's frame of reference it is not so in the observer's frame of reference the clock is moving at velocity v.

Now, you clearly understood how to calculate from the moving observer, but when I switched to the clock as the frame, you have expressed all this anger and hostility.

So, that was my thought process.

Now, are you going to calculate the time dilation with light aberration from the clock frame as the frame or no.

The time dilation of the clock? or the time dilation of the observer that's in another frame of reference?
 
  • #288
JesseM said:
I'm not talking about which frame is "moving" or "stationary" because those are just arbitrary labels which have nothing to do with calculating anything. I'm asking whether you acknowledge that you changed your scenario, first saying the observer was at rest relative to the clock and then accusing me of an error when I discussed what would be true if the observer was at rest relative to the clock. This is a simple question, can you stop changing the subject and address it?

I said above I saw no chance of have the moving frame considered moving in this forum. I said that.

So, I decided to take the view of the clock frame. So, if you want to say I changed it, I did but did not. I still taking the clock frame as stationary as I did in the OP.

So, I have addressed it. What is your problem?
 
  • #289
darkhorror said:
That is exactly what the article says we are calculating from the observer's frame of reference the observer is moving at velocity v with respect to the clock. So when you calculate from the "moving observer's" frame of reference it is at rest in that frame of reference.



The clock's frame is only at rest in it's own frame of reference. In the observer's frame of reference it is not so in the observer's frame of reference the clock is moving at velocity v.



The time dilation of the clock? or the time dilation of the observer that's in another frame of reference?

OK, take all this and revert to the clock frame.

What is the calculation?
 
  • #290
chinglu1998 said:
I said above I saw no chance of have the moving frame considered moving in this forum. I said that.

So, I decided to take the view of the clock frame. So, if you want to say I changed it, I did but did not. I still taking the clock frame as stationary as I did in the OP.

So, I have addressed it. What is your problem?

The point once again is that it doesn't matter which frame you call stationary or moving. All you have are two frames of reference A and B. where one or the other is stationary or moving, it doesn't matter which is which.

So you have two frames of reference A and B moving relative to each other at velocity v.

Here are two very simple questions can you answer them without any other information?

From frame of reference A does B's time move slower?

From frame of reference B does A's time move slower?
 
  • #291
chinglu1998 said:
So, I decided to take the view of the clock frame. So, if you want to say I changed it, I did but did not. I still taking the clock frame as stationary as I did in the OP.

So, I have addressed it. What is your problem?
I'm not talking about which frame you "took the view of". I'm talking about whether the clock is moving or stationary relative to the observer. If the clock is moving relative to the observer, then they are in relative motion regardless of whether you take the view of the clock frame or the observer frame. If the clock is stationary relative to the observer, then they are not in relative motion, again regardless of which frame you adopt. Are you going to acknowledge the fact that you said "the clock at rest wrt to the observer", then accused me of mistakes and errors when I talked about the scenario where the clock is at rest wrt to the observer?
 
  • #293
chinglu1998 said:
OK, take all this and revert to the clock frame.

What is the calculation?

and I will ask again calculation of what? as I asked before

Are you asking
1. What is the time dilation of the clock in it's own frame of reference?

2. What is the the observer's time rate when looked at from the clocks frame of reference?

if you are asking 1. there is not time dilation it ticks at normal rate since it's velocity in that frame is 0.

if you are asking 2. the observer's time rate will be slower than the clocks since you are looking from the clocks frame of reference.

Now to add one more thing if you are looking from the observer's frame of reference then the clock ticks slower since it's moving with velocity v with respect to the observer.
 
  • #294
chinglu1998

Would it make sense to you if the wiki article said this instead.

so instead of this "Observer at rest sees time 2L/c." they wrote this
"From the clocks frame of reference it sees time 2L/c."


and
instead of "From the frame of reference of a moving observer traveling at the speed v..."
"From the frame of reference of an observer with the clock traveling at velocity v..."
 
  • #295
chinglu1998 said:
I could ask you how does the observer that is moving in the WIKI artricle has any time.
There are many methods of measuring time. However, since this is an abstract physics problem I don't see why time can't be defined in a more abstract manner e.g. as one of the consitituent dimensions of space-time that can be given a more or less arbitrary unit duration (just like the spatial dimensions can be given arbitrary units of length).
chinglu1998 said:
Assume the clock and light source are at reat.
chinglu1998 said:
So, t'/γ = t.

The primed frame is the moving frame.
Yes, this is the conclusion of the calculation in the wikipedia article as well. If you have two light clocks, one at rest in the primed frame and one at rest in the unprimed frame, then you can use light aberration to show time dilation is symmetric. (Each clock will exhibit light aberration and time dilation from the other frame and the values will be equal in magnitude.)
 
  • #296
inflector said:
Why does this thread give me deja vu?

Oh, that's right:

http://www.bautforum.com/showthread...eeds-light-to-travel-faster-than-c-to-be-true

This has nothing to do with that thread. It was a spinoff and different issue.
But, it had is points that Baut cannot see.

I never got to the point.

You see, if an observer rides a light beam, the entire universe becomes a plane in the direction of travel to the observer.

Yet, from the non observer, (non-light observer), light does not traverse the entire universe instantly.

So, the two logical conclusions are not invertible and hence not mathematically viable as a complete theory.
 
  • #297
darkhorror said:
and I will ask again calculation of what? as I asked before

Are you asking
1. What is the time dilation of the clock in it's own frame of reference?

2. What is the the observer's time rate when looked at from the clocks frame of reference?

if you are asking 1. there is not time dilation it ticks at normal rate since it's velocity in that frame is 0.

if you are asking 2. the observer's time rate will be slower than the clocks since you are looking from the clocks frame of reference.

Now to add one more thing if you are looking from the observer's frame of reference then the clock ticks slower since it's moving with velocity v with respect to the observer.


Using light aberration as the WIKI article, calculate the time intervals in he different frames. Assume the clock is the frame you are calculating from.
 
  • #298
JesseM said:
I'm not talking about which frame you "took the view of". I'm talking about whether the clock is moving or stationary relative to the observer. If the clock is moving relative to the observer, then they are in relative motion regardless of whether you take the view of the clock frame or the observer frame. If the clock is stationary relative to the observer, then they are not in relative motion, again regardless of which frame you adopt. Are you going to acknowledge the fact that you said "the clock at rest wrt to the observer", then accused me of mistakes and errors when I talked about the scenario where the clock is at rest wrt to the observer?

I am not even sure what to say with you.

The clock is at rest relative to the observer. I have said this and said this and said this and said this and said this and said this.
 
  • #299
darkhorror said:
chinglu1998

Would it make sense to you if the wiki article said this instead.

so instead of this "Observer at rest sees time 2L/c." they wrote this
"From the clocks frame of reference it sees time 2L/c."


and
instead of "From the frame of reference of a moving observer traveling at the speed v..."
"From the frame of reference of an observer with the clock traveling at velocity v..."

Yes, the above makes sense to me no matter how anything is calculated.
 
  • #300
IsometricPion said:
There are many methods of measuring time. However, since this is an abstract physics problem I don't see why time can't be defined in a more abstract manner e.g. as one of the consitituent dimensions of space-time that can be given a more or less arbitrary unit duration (just like the spatial dimensions can be given arbitrary units of length).Yes, this is the conclusion of the calculation in the wikipedia article as well. If you have two light clocks, one at rest in the primed frame and one at rest in the unprimed frame, then you can use light aberration to show time dilation is symmetric. (Each clock will exhibit light aberration and time dilation from the other frame and the values will be equal in magnitude.)[/QUOTE]

No you cannot.

We have one light source and the clock is at rest with the light source.
 
  • #301
chinglu1998 said:
Using light aberration as the WIKI article, calculate the time intervals in he different frames. Assume the clock is the frame you are calculating from.

So your asking both 1 and 2?
 
  • #303
chinglu1998 said:
IsometricPion said:
There are many methods of measuring time. However, since this is an abstract physics problem I don't see why time can't be defined in a more abstract manner e.g. as one of the consitituent dimensions of space-time that can be given a more or less arbitrary unit duration (just like the spatial dimensions can be given arbitrary units of length).Yes, this is the conclusion of the calculation in the wikipedia article as well. If you have two light clocks, one at rest in the primed frame and one at rest in the unprimed frame, then you can use light aberration to show time dilation is symmetric. (Each clock will exhibit light aberration and time dilation from the other frame and the values will be equal in magnitude.)[/QUOTE]

No you cannot.

We have one light source and the clock is at rest with the light source.

it's ONLY at rest from clocks frame of reference. From the "moving observer" frame of reference the clock IS MOVING, and the observer is at rest.
 
  • #304
Aren't you all starting to feel like Sisyphus?

I watched this go on for 100 posts in another forum, this one has gone over 300 but made no tangible progress as far as I can tell.
 
  • #305
inflector said:
this one has gone over 300 but made no tangible progress as far as I can tell.
Yeah. Regardless of how often it is mentioned, he still doesn't seem to get the most basic concept about relativity which has been around since Galileo: velocities are relative. And he certainly doesn't understand the basic idea that all inertial frames are equivalent. And he doesn't understand the Minkowski metric. So it is really hard to make any progress, particularly when he thinks that he understands all of those things.
 
  • #306
chinglu1998 said:
I am not even sure what to say with you.

The clock is at rest relative to the observer. I have said this and said this and said this and said this and said this and said this.
Except when I said the clock is at rest relative to the observer, you said this was a mistake:
chinglu1998 said:
Where in the WIKI article is the clock at rest with the observer? You make many mistakes.
And since then you have said and said the exact opposite, that the clock is not at rest relative to the observer (click the little arrows after your name to see the full posts):
chinglu1998 said:
the observer is moving relative to the clock.
chinglu1998 said:
We are trying to calculate the clock at rest and the observer is moving
So yeah, if you can't look at these posts and acknowledge that you repeatedly contradict yourself about whether the observer & clock are in relative motion or are at rest relative to one another, you are either trolling or have a mental disorder.
 
  • #308
Bottom line is that in any frame where the clock is moving it is time dilated. This is what the wikipedia article said in the formulas it derived, so it is correct.

In any frame where the clock is not moving it is not time dilated. This is also what the Wikipedia article said simply by setting v=0 in the formulas derived.
 
  • #309
Maybe "relative" means something different in whatever language is chinglu's first language. Maybe when he says: "The clock is at rest relative to the observer." he doesn't mean what we think he means but rather that: "The clock is at rest while the observer is not."

If that's the case, I can see it being possible that all four of the quotes mean the same thing:

"The clock is not moving" and "The observer is moving"

in some sort of preferred and absolute coordinate system.

But, of course, there is that little problem that DaleSpam, and Galileo and Einstein before him, alluded to of relativity of movement. It's kind of hard for one thing to be moving relative to another and not have the reverse be true as well. This doesn't seem apparent to chinglu, however. He also doesn't seem particularly open to the idea that he might be wrong or mistaken in either his logic or use of the English language.
 
  • #310
inflector said:
Maybe "relative" means something different in whatever language is chinglu's first language. Maybe when he says: "The clock is at rest relative to the observer." he doesn't mean what we think he means but rather that: "The clock is at rest while the observer is not."
Then why would he say this: "Where in the WIKI article is the clock at rest with the observer? You make many mistakes."

The most charitable interpretation would just be that he inconsistently changes his terminology to "win" the argument without really realizing what he is doing, but if he can't acknowledge the inconsistency even when presented with side-by-side quotes, it's a lot more likely that he's just a troll intentionally playing dumb to annoy people.
 
  • #311
chinglu1998 said:
No you cannot.

We have one light source and the clock is at rest with the light source.
That is true in the wikipedia article, and they successfully use that setup to derive time dilation (as you showed in calculations earlier in the thread and as they show on the wiki). Why would it be unreasonable to introduce a additional light clock that is at rest in the primed frame?
 
  • #312
JesseM said:
Then why would he say this: "Where in the WIKI article is the clock at rest with the observer? You make many mistakes."

The most charitable interpretation would just be that he inconsistently changes his terminology to "win" the argument without really realizing what he is doing, but if he can't acknowledge the inconsistency even when presented with side-by-side quotes, it's a lot more likely that he's just a troll intentionally playing dumb to annoy people.
Even in this case: "The clock is at rest with the observer" he might think means "Clock is at rest with respect to the observer that is moving."

Still, who knows? He certainly could be playing dumb.

All I know is that trying to teach him SR in English is not fruitful.
 
  • #313
chinglu1998 said:
WIKI has possible error with time dilation.

Does anyone agree?

I think this has been answered. No, nobody agrees.
 

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