Twin paradox (Pete and MacM)

[MacM]

MacM:

Most of your post contains no substance, so I'll ignore those parts and only reply to the substantive parts.

I am not sure what you're "no" refers to.

Are you answering "no" to Pete's question? In other words, are you now agreeing that when light is emitted simultaneously from A and B it does not reach the other clock simultaneously? Please be clear.

"No" means signals do not have to be simultaneous in all frames of reference. But that doesn't alter the ultimate conclusion regarding clocks not recording time dilation or the fact that A - B = 0 regardless of when and how that occurs.

As for simultaneity addressing reciprocity, you still haven't defined "reciprocity" well enough for me to be able to answer. More on this below. I note that the term "reciprocity" is hardly ever, if ever, used in relativity.

Yes. LOL.

The term "symmetry" in physics is used more widely than your definition. It is usually used to refer to a property of a system which stays the same when some kind of transformation is made on the system. Thus, if elapsed time for two observers is the same when similar processes occur then we can say that there is a symmetry between the observers, for example.

Your definition of "reciprocity" is circular, and therefore seems to be useless. It is also vague.

What is it supposed to mean in the context of relativity?

Please explain, and give an example of a curve which is not symmetrical but which has reciprocity.

Figure to be posted.

I have already read the problem. The required information is not in it, as I said.

It most certainly is.

I have answered the tick rate questions, which is the most that can be done with the given information.

Not for those that actually have a grasp of facts. Since you have conceeded that the tick rate views of both clocks do not differ, i.e. - show EQUAL slowing of time flow rate. It becomes natural that accumulated time must also be equal.

If relative velocity does not alter tick rates it cannot alter accumulated time.

Which was when? I asked this before.

When?

When did they shut them off? I asked this before, too. Remember?

Irrelevant to the issue at hand.

Your last statement here bears no relation to the ones before. You seem confused.

No. I can do that. You haven't specified t1.

WQhen considering relative velocity affect on tick rates one does not need to specify a time. t1 becomes 1.000. I would have thought you learned that in college. :bugeye:

I already answered your questions about tick rates. The ones I couldn't answer were about total elapsed times. Try to keep up.

Ditto.

You haven't specified t1.

As stated not necessary. Irrelevant. Tick rates are equally affected. No net tick rate change. No tick rate change means no accumulated time differance in a given period and physical clocks support this view. They can not record a time shift.

False. The rest frame is just another frame, like any other.[/qluote]

False conclusion. The rest frame is not special in any manner "Other than the fact it is the only frame that the clock physically exists to itself and where it ticks and records time for itself." I happen to think that is somewhat special.

It is why you assign t = 0 when doing relavistic calculations. t = 0 is the rest frame. Yet you want to claim it isn't special. however you always use it to do your calculations. Can you explain your duplicity of being special and not being special?

What is this "reciprocity" thing? Why does it not appear in any text on relativity, if it is so important? Oh, that's right. The people who write the textbooks don't know what they are talking about. Yeah, sure.

A very good possibility actually. Considering how blinded you seem to be to the bottom line physical facts. Education clearly doesn't guarantee common sense and understanding.

Let me know when you reach a conclusion.

I most likely won't worrry about it since it has nothing to do with this issue.

When did you stop beating your wife?

I think my point is made regarding your loaded question demanding yes or no answers.

I thought you specified constant velocity only. The twin paradox involves acceleration. Make up your mind.

The general use of the principles of the twin paradox is to laime the fountain of outh and travel into the future by putting around in space at relavistic velocities.

This issue has been discussed and it is understood that the twin issue involves GR (gravity) and acceleraton, but it is also claimed that the accumulated time is affected by the relative velocity.

Further I have already mentioned several times that the reciprocity issue is not limited to merely constant relative velcoity but to cases where there is equal acceleration curves.

Then you find me one quote from a published source which says "the muon decay experiments prove that relativity is correct", or something of that kind.

Oh, I see you rather want to litmit your claim now. Forget searching for published claims (although I will because I suspect they are their) but lets concentrate on why you didn't correct Billy T's claim that muon decay proves time dilation?

A bit one sided here aren't we. Statments are only challenged when they are used against Relativity but are allowed when they support Relativity.

No reciprocity here for sure.

I have no idea what you're talking about. There are no inconsistencies in my statements. If there were, you could point them out by quoting the relevant parts and showing the inconsistency.

Instead, you just make unsupported assertions, as usual.

Incrediable.

1 - You agree that relative velocity when applied to both views does not show net time dilation.

2 - You agree that if a clock shows time dilation under constant relative velocity conditions it does not prove Relativity but violates it.

Yet. In this thread you claim that those statments are false. Make up your mind which is it. Stop flip flopping all over the place and trying to bring in irrelevant issues.

 

[Persol]

2 - You agree that if a clock shows tme dilation under constant relative velcoity conditions it dows not prove Relativity but violates it.

Please show where JamesR said this, because you just threw context out the window.

 

[MacM]

Please show where JamesR said this, because you just threw context out the window.

http://www.sciforums.com/attachment.php?attachmentid=3355&stc=1

 

[Persol]

... from a 'stationary' point in between where SpeedA=SpeedB.

 

[MacM]

... from a 'stationary' point in between where SpeedA=SpeedB.

That is not what was being discussed nor what was said. While that would cause the third observer to see equal affects, his view would still be in contrast to actual accumulted time on each clock.

At 0.9c his view of each clock would have the tick rate as being 0.893 as fast as each clock would claim they were ticking.

The issues of perception vs reality is still valid. The only valid conclusion is that the physically recorded times by the clocks are reality and any other view must be perception.

Those views are restricted to remote observation while in relative motion and are not recorded by the clocks physically on ultimate side by side comparison in a common rest frame..

 

[Pete]

I can be mistaken or make an error but I do not lie

Perhaps not, but self-delusion also looks a lot like it.

I do resent his tendancy to think that denegarating other elevates himself.

I think you're projecting.

But, that's all completely irrelevant as far as I'm concerned. Psychological neuroses tha tvarious posters may or may not have don't affect the question of whether it is possible to sychronize two moving clocks.

So, please return your attention to [post=693646]post 693646[/post].

Are you certain that "any change in the system relative between clocks will be observed by each clock at the same actual instant if the change(s) are induced locally at each clock at the same instant"?

 

[Pete]

The only valid conclusion is that the physically recorded times by the clocks are reality and any other view must be perception.

Interestingly, when the clocks are stopped at the same time in some other frame (not the mean velocity frame), the physically recorded times are different.

The only valid conclusion is that the physically recorded times are reality, wouldn't you agree?

 

[Persol]

That is not what was being discussed nor what was said.

Well yes, it was. You simply misinterpretted what was a simple statement.

While that would cause the third observer to see equal affects, his view would still be in contrast to actual accumulted time on each clock. At 0.9c his view of each clock would have the tick rate as being 0.893 as fast as each clock would claim they were ticking.

Yes, the accumulated time would be the same in the stationary frame of reference.

The issues of perception vs reality is still valid. The only valid conclusion is that the physically recorded times by the clocks are reality and any other view must be perception.

JamesR's comment in no way supported your view of this... and you have yet to provide anything that supports this. You just keep saying it.

 

[James R]

MacM:

"No" means signals do not have to be simultaneous in all frames of reference.

Noted for future reference.

Since you have conceeded that the tick rate views of both clocks do not differ, i.e. - show EQUAL slowing of time flow rate. It becomes natural that accumulated time must also be equal.

I did not agree that the tick rates do not differ. In fact, I said exactly the opposite. A's tick rate and B's tick rate, when measured in the same frame of reference are different.

As I said before, accumulated time depends on when the clocks are started and stopped, as well as tick rate. Think about it. It is obvious. And you haven't specified it.

Instead of whinging and whining and claiming that you have specified it before, why not just specify it?

WQhen considering relative velocity affect on tick rates one does not need to specify a time.

Correct.

Are you capable of distinguishing between a tick rate and an accumulated time, MacM?

The rest frame is not special in any manner "Other than the fact it is the only frame that the clock physically exists to itself and where it ticks and records time for itself." I happen to think that is somewhat special.

So, you are now claiming that objects become imaginary once they start moving, are you?

If we are in the same room, and I start walking across the room, then I suddenly don't physically exist any more, because I am no longer at rest.

You're losing it.

It is why you assign t = 0 when doing relavistic calculations.

No.

Setting t=0 is arbitrary. You can start a clock when it reads whatever value you like. Start your clock at t=27 hours. It makes no difference.

t = 0 is the rest frame.

No it isn't. Refer to your own definition of what a reference frame is, given above. Or, if you're not sure, you can ask me and I'll explain.

Yet you want to claim it isn't special.

It isn't.

however you always use it to do your calculations.

No. I can do the calculations in any frame you like. Recently, Pete has been showing you the mean velocity frame between 2 clocks, just for a change of pace.

Can you explain your duplicity of being special and not being special?

There's nothing to explain.

Education clearly doesn't guarantee common sense and understanding.

But lack of education is a sure-fire guarantee of a lack of understanding.

I most likely won't worrry about it since it has nothing to do with this issue.

You're talking about relativity, and you say that reference frames have nothing to do with the issue.

Poor confused MacM.

Then you find me one quote from a published source which says "the muon decay experiments prove that relativity is correct", or something of that kind.

Oh, I see you rather want to litmit your claim now. Forget searching for published claims (although I will because I suspect they are their) but lets concentrate on why you didn't correct Billy T's claim that muon decay proves time dilation?

Why don't you post Billy T's statement that the muon experiments prove relativity, then?

1 - You agree that relative velocity when applied to both views does not show net time dilation.

2 - You agree that if a clock shows time dilation under constant relative velocity conditions it does not prove Relativity but violates it.

Yet. In this thread you claim that those statments are false. Make up your mind which is it. Stop flip flopping all over the place and trying to bring in irrelevant issues.

Remember this?

You misunderstand. The post you keep referring to regarding my "admission" considered a different scenario to the one presented in the original "two clock" problem in this thread, and also different to the "2 car" problem used in my derivation.

I agreed that there would be no difference in clock readings in a situation where the clocks were started and stopped symmetrically. To be explicit, let me give you that scenario:

"Two clocks, A and B, set out from the origin, with clock A travelling at +0.45c and clock B travelling at -0.45c relative to a stationary observer. All motion is at constant speed for the whole time. When each clock reads a pre-agreed time in its rest frame, that clock sends out a light pulse towards the other clock. Each clock calls the time the pulse is sent out time "zero". Each clock continues to run locally until the pulse is received from the other clock, at which time the local clock is stopped. The two clocks are then brought back together and their elapsed times compared."

In this scenario, both clocks will show the same final reading.

This scenario differs from the 2-clock scenario presented earlier in this thread in that 2 different signals are used to stop the clocks. In contrast, in our original scenario, and in my derivation thread, only one signal is used. The scenario presented in the paragraph above is a symmetrical one, and so no overall time difference is recorded. The orginal scenario is not symmetrical, so the effects of time dilation are not masked there.

Stop with the stupid claims, ok?

 

[Pete]

"No" means signals do not have to be simultaneous in all frames of reference.

Can you please clarify - are you now denying your assertion in your clock synchronization process that "any change in the system relative between clocks will be observed by each clock at the same actual instant if the change(s) are induced locally at each clock at the same instant"?

 

[MacM]

Perhaps not, but self-delusion also looks a lot like it.

I think you're projecting.

But, that's all completely irrelevant as far as I'm concerned. Psychological neuroses tha tvarious posters may or may not have don't affect the question of whether it is possible to sychronize two moving clocks.

So, please return your attention to [post=693646]post 693646[/post].

Are you certain that "any change in the system relative between clocks will be observed by each clock at the same actual instant if the change(s) are induced locally at each clock at the same instant"?

Actually "No". Your diagrams are good evidence that perspective alters the conclusion of what is simultaneous. However, I hasten to add that what it actually shows is the ongoing affect of Relativity being that of a perception rather than reality.

Your post shows the timing from one perspective. Now reverse that perspective, just as I have done for time dilation and you lfind the reverse is true.

You actually make it fairly easy to pose an interesting question. Since it would appear that in one direction the light takes 1 second to reach the observer and 10 seconds (basied on a relative veloicty of 0.9c) to reach the other.

However, that situation referse when you rightfully change your view of who is at rest.

The question becomes this what does recievers mounted to each clock show was the respective time they receive light after having transmitted light?

Just as with clocks and accumulated times displayed, the answer that is reality is the one, and only one, that the recievers record and the recievers CANNOT record two different time delays between transmittal and recepit of light.!!!

Whatever that recorded time delay is it is going to be equal in both directions. That will be the reality and not the two different times as projected by Relativity. That is mere perception based on a moving observers view.

NOW. Do you agree that the recievers can and will only record one time delay? Yes or No.

If "Yes" then explain how you want to claim two different times as being reality.

If "No" then please explain how you get these physical devices to record two different numbers.

Do you still claim there is no problem with Relativity?

 

[MacM]

Interestingly, when the clocks are stopped at the same time in some other frame (not the mean velocity frame), the physically recorded times are different.

The only valid conclusion is that the physically recorded times are reality, wouldn't you agree?

NO. The method of stopping you use discount simultaneity time delay of information.

 

[MacM]

Well yes, it was. You simply misinterpretted what was a simple statement.
Yes, the accumulated time would be the same in the stationary frame of reference.
JamesR's comment in no way supported your view of this... and you have yet to provide anything that supports this. You just keep saying it.

Pointing out once again you have posted mere words and no evidence.

 

[Pete]

NO. The method of stopping you use discount simultaneity time delay of information.

YES. Please parse your sentence again - I have no idea what you're trying to say.

 

[MacM]

MacM:

Noted for future reference.

Fair enough just don't misapply that fact to make unsupported claims.

I did not agree that the tick rates do not differ. In fact, I said exactly the opposite. A's tick rate and B's tick rate, when measured in the same frame of reference are different.

You like to give then take. Your comment is a qualified one which declines to consider the issue of reciprocity of data.

Are you capable of distinguishing between a tick rate and an accumulated time, MacM?

Don't be silly.

So, you are now claiming that objects become imaginary once they start moving, are you?

Don't be silly. You always exist instantly at a point in rest, i.e. t=0 is the present. Motion is also a change marked by both shifting into the past and future simultaneously. It also produces perception shifts of reality as Relativity makes clear. But you do not cease to exist.

If we are in the same room, and I start walking across the room, then I suddenly don't physically exist any more, because I am no longer at rest.

You're losing it.

No, you already lost it. You are always at rest. t=0 is the present and at every instant of present you cannot be in motion. You exist at x,y,z,t, not x,y,z,t -------->x',y',z',t

 

[MacM]

Can you please clarify - are you now denying your assertion in your clock synchronization process that "any change in the system relative between clocks will be observed by each clock at the same actual instant if the change(s) are induced locally at each clock at the same instant"?

Hopefully clarified in response to your post above. If not give a yell.

 

[Paul T]

No, you already lost it. You are always at rest. t=0 is the present and at every instant of present you cannot be in motion. You exist at x,y,z,t, not x,y,z,t -------->x',y',z',t

Damn, this is a stupid concept. This is MacM's relativity?

 

[James R]

MacM:

Your problem with the definition of a reference frame is becoming more and more relevant.

Don't be silly. You always exist instantly at a point in rest, i.e. t=0 is the present.

If I set my watch right now to t=0, then in two minutes time I will exist at t=2 minutes, according to me. According to you, then 0.0000001 seconds after now, I cease to exist.

The time t=0 does not shift. What shifts is objects or people in spacetime. In particular, even when they sit still in space, they still move through time.

I exist at t=0. But I also exist at all other times, during my life span.

In light of this new knowledge, you might like to reconsider the meaning of the spacetime diagrams previously presented to you.

Motion is also a change marked by both shifting into the past and future simultaneously.

No object ever moves into the past and future simultaneously.

You are always at rest.

Then how do you account for the fact that I can walk across the room?

t=0 is the present

Wrong. t=0 is one 3 dimensional slice of a 4 dimensional spacetime. It is the whole of space as it exists at one set time.

and at every instant of present you cannot be in motion.

That is incorrect. At t=some value, any object might be travelling at velocity v.

You exist at x,y,z,t, not x,y,z,t -------->x',y',z',t

(x,y,z,t) is one coordinate system. (x',y',z',t') is another coordinate system. I exist in both coordinate systems, provided they refer to the same universe - the one that I am in.

 

[MacM]

Damn, this is a stupid concept. This is MacM's relativity?

I would be interested to see you explain your existance at some other time than t=0.

 

[James R]

To all interested people:

There has been much confusion about what a reference frame is or is not.

For that reason, I have started a thread, explaining the concept for those who, like MacM, are confused about the concept. Here it is:

http://www.sciforums.com/showthread.php?p=694403#post694403