esbo

It is mainly an upper class public school thing, I see so many who cannot pronounce an 'r', you often

see them on the BBC when they are interviewing an 'expect' on something, experts are nearly always

upper class as they can afford the education.

They look Widiculous!!

 

Relativity, which has been experimentally and observationally verified to an amazing degree over the last hundred years tells us that there is no absolute frame of reference.

 

 

The rate of expansion is about 78 km/sec/megaparsec. This means that the rate of expansion increases by 78 km/sec for every 3.26 million light years. This is a very low expansion rate.

 

Yes, there's quite a bit we don't yet know. The surprising thing is how much we've been able to learn about the universe in just the last 200 years.

Merely saying "relativity" is not evidence, nor is saying "Relativity, which has been experimentally and observationally verified to an amazing degree over the last hundred years tells us that there is no absolute frame of reference."

If it has been experimentally verified tell me about the experiment, I mean you must be pretty familiar with the experiment? Yes?

I asked how strong the force of expansion was, not the rate of expansion, I can easily look that up, bit harder finding the force of expansion.

As there is quite a bit we do not know, that seem to leave a lot of room for error in what we *think* we know.

Whilst we think we have learned a lot in the last 200 years we may well learn much if it is wrong in the next 200 years.

 

Velocity is always relative to something. There is no place that can be said to be absolutely static, therefore, there can be no preferred frame of reference.

 

What time it is from any given frame of reference is a function of the strength of the gravitational field it resides in and the velocity it moves at relative to some other frame. Again, there is no preferred frame.

It doesn't matter what clock you use -provided it has sufficient resolution for the test to measure any difference- it will agree with the predictions of Relativity.

Very weak compared to gravity...it occurs between superclusters at distances about 200 million light years apart or more.

 

The expansion is a consequence and continuation of the BB...dark energy was postulated to explain the increasing rate of that expansion over time.

What evidence is there that there is no absolute reference point of velocity and the same goes for time, where is the evidence?

How strong is the force of expansion specifically, can you give a number?

Given we do not know what dark energy is it seems there is a lot we do not understand about the universe

I am lead to believe this is the case, if it's not then well I guess I am wasting my time!!

So.....if they are how is this possible, we are told this is impossible.

It seems to be the case that people will say yes some are moving faster than the speed of light but that is

because space if expanding.

That leads to new questions such as, how fast are they really moving.

It seems to me that nothing is moving very fast really indeed I think that basically everything

is basically pretty static and that there is a standard time for the universe which I will call 'real-time'.

So I think there is a common reference point for time and that any different time of moving objects

are basically due to 'clock error' so we could refer to their time as standard time - clock error.

Also what if we tied two galaxies together with a rope?

Would they stop moving apart? Or would the rope snap?

Basically how strong is the force of expansion?

Maybe this is something to do with dark energy?

Maybe someone can explain?

Just to throw in my answer, B's world has contracted to due to the extra gravity, thus distance has changed and makes up for the change in time thus giving the same answer for C.

I just know I am right on this one so please tell me I am right and email me my Nobel prize for physics. (just the money I have no more room for trophies).

I mean B's rular has contracted (or expanded).

Any how point is the light arrives at the same time for both, so I am thinking this is to do with simultaneousness,

I mean lets face it they do not know what time the light was sent out only when it arrived.

So yea it does arrive at different times on each's clock (but at the same time really )

But the BIG thing is neither know when the light pulse was sent out, all they see is darkness until there is light.

I think that is the key point, the length contraction is a different minor issue I would imagine.

I guess you could learn more if he sent out two light pulse say 1000 seconds apart, that might be

a more meaningful problem, then again it might not especially if you made a mistake with your logic.

The local speed of light is "c" even in rotating frames. There are preciously few papers on this subject but there are a few very good ones. So, esbo claim is false, he mixes the speed of light with closing speed. Closing speed is indeed [math]c \pm \omega r[/math], as evidenced by the class of experiments known as "Sagnac experiments".

Why claim is false, I am not aware of making a claim, I am basically say, ""explain this".

So what specifically are you referring to when you say my claim is false.

I am not sure so perhaps you could refresh me on the claim you say i have made.

From the perspective of the sun. If you have two observers moving in opposite directions with respect to the sun, the sun is most definitely moving as seen by one or both observers.

Well not really the sun is stationary and they are the ones moving.

OK, then: closing speed is always measured to be c in your frame. Relative motion of the light source only changes the frequency of the light.

I know c is always measured as a constant, I just want the apparent anomalies explain but in a specific rather than generic way.

The sun is not moving in the example, or at least not considered to be.

This is basically about math. Regardless of how you view, or believe in, the physics,

SR is consistent mathematically. So if you use SR, as an underlying assumption, in a thought

experiment and come up with a conflict in the results, you have either made a mistake as to how to use the theory, or made a mathematical error, or have proven the math of SR itself incorrect. So if you are convinced you have not made an error...where exactly is the math of SR inconsistent or wrong?

 

If you do not believe SR is mathematically consistent, point out the inconsistency.

Well there are examples which can be used and have been used to point out inconsistency.

What I am saying is look at this example, it does not seem to fit with SR, where is the error.

Now I think it is reasonable to expect someone to point out the error rather than simply parrot out some line

about SR or maths or simultaneous need. I am finding those kind of non answers rather tiresome.

And the "this is about maths bit" is a bit silly, it is about the question asked and the solution, the examples point out the inconsistencies

that is the whole point of them.

The error is pointed out in the examples provided,.

the best way of to replying to a response like yours would be to simply repeat the question, however I won't do that, but you can

read it again if you so wish, and that is your answer.

The spinnin earth is not actually an inertial frame. If you do an experiment where the spin is important, e.g. send light one way vs the other, around the equator, you will notice the effect of the spin.

 

But in an inertial set of frames, moving toward or away from the light will not affect the speed you measure.

The spinning of the earth is pretty irrelevant to the question, the point is they are moving in opposite directions and that was just a

way of illustrating that point.

I don’t usually post to these forums because I don’t have time to do a back and forth dialog. But I have to reply to this thread. The “paradox” presented by the author that esbo referenced is so basic it could be given as a homework problem to a student taking “Introduction to Special Relativity”. The key to the resolution, as has already been mentioned, is Relativity of Simultaneity.

 

Let me walk thru the homework problem.

 

Given:

You are sitting on the surface of the Earth monitoring a box of decaying muons with a clock. I am monitoring an identical box of decaying muons with my own clock. But I am at an altitude of 10 light-seconds above hurtling toward you at .866c. (10 light-seconds is the distance light travels in 10 seconds). We both start monitoring at the same time according to you.

 

As far as you are concerned, when I reach you, 11.55 seconds will have elapsed on your clock (10c/.866c). But only 5.77 seconds will have elapsed on my clock since my clock is running at 50% of yours. Since less time has elapsed for me, you expect that I will have more muons in my box than you have in your box.

 

Assignment:

Analyze the problem from my reference frame. What do I expect?

 

Solution.

From my point of view, the distance to you is only 5 light seconds (50% length contraction). So I expect to meet you when 5.77 seconds have elapsed on my clock (5c/.866c) and I expect to have an amount of muons in my box consistent with that time. That’s the same time (and the same amount of muons) as you expected for my clock and my box. So far, no contradiction.

 

Now for the hard part.

I believe your clock is running at 50% the rate of my clock. So if 5.77 seconds elapsed on my clock, only 2.89 seconds will have elapsed on your clock between the time I started monitoring and the time we met. But it was given that 11.55 seconds elapsed on your clock when we met. I’m standing right next to you. I have to see the same number on your clock or there is a paradox. How do I resolve that? Well, you must have started monitoring 17.33 seconds before I started monitoring. Since your clock was running at 50%, 17.33 /2 means 8.67 seconds already elapsed on your clock before I even started my clock. Add 2.89 more seconds while both of us were monitoring and I will expect 11.55 seconds elapsed on your clock when we meet. That eliminates the contradiction. If you’re thinking I invented my answer just for this problem, I didn’t. It’s part of the theory.

 

To Summarize:

From your point of view we both started monitoring our boxes of muons at the same time. From my point of view you started monitoring your muons 17.33 seconds before I started monitoring mine. What is simultaneous to you is not simultaneous to me. That’s how Length Contraction, Time Dilation and Relativity of Simultaneity work together to eliminate any contradiction.

 

Can I show that using actual calculations? Sure. I could post some equations with the right numbers on the other side of the “equals” sign. Would you then be convinced? I doubt it.

 

 

 

OK I have had a bit more time on this, and it sort of sound plausible to some extent apart from the fact I am not too happy with length contraction.

It's perhaps better if that is addressed first as follows.

Now,as I understand it we will always measure the speed of light as a constant.

So say you have two people on opposite side of the earth measuring the speed, one spinning towards the light and one away from it.

Because of the earth's spin on it's axis they are both doing the same speed but in opposite direction (we can ignore orbit speed to keep it simple).

So doing the same speed they will the same (rate of) time, correct??

And also the same length contraction? Correct?

So that is the problem, how can they measure the same speed when light has to travel further over the identical metre ruler they had when they

met up?

You see the problem is one ruler is travelling towards the light and one away so light will have to go further to cross the ruler moving away from the light.

So I do not quite see how someone can answer this with "oh it's due to simultaneousness".

Or maybe you can?

I suppose you can say one twin could be considered stationary and the other travelling at twice the rate of spin???

So either way it is a bit confusing to think about when things we take for granted change.

So what is the explanation to that problem, is it as I said?

So you could say for the stationary one there is no contraction, but there is for the one moving towards the sun so his length will contract

*and* his time will slow down. AT first though that seems to give the opposite of the what I want to explain it, but I am not sure.

I need to think about it a bit more, I think. It might give the answer possibly.

I suppose if the ruler length is the distance light travels in a second and his time is slower then it will not have travelled as far

consistent with his shorter ruler?

But I am not OK with that yet, need to give it more though.

I don’t usually post to these forums because I don’t have time to do a back and forth dialog. But I have to reply to this thread. The “paradox” presented by the author that esbo referenced is so basic it could be given as a homework problem to a student taking “Introduction to Special Relativity”. The key to the resolution, as has already been mentioned, is Relativity of Simultaneity.

 

Let me walk thru the homework problem.

 

Given:

You are sitting on the surface of the Earth monitoring a box of decaying muons with a clock. I am monitoring an identical box of decaying muons with my own clock. But I am at an altitude of 10 light-seconds above hurtling toward you at .866c. (10 light-seconds is the distance light travels in 10 seconds). We both start monitoring at the same time according to you.

 

As far as you are concerned, when I reach you, 11.55 seconds will have elapsed on your clock (10c/.866c). But only 5.77 seconds will have elapsed on my clock since my clock is running at 50% of yours. Since less time has elapsed for me, you expect that I will have more muons in my box than you have in your box.

 

Assignment:

Analyze the problem from my reference frame. What do I expect?

 

Solution.

From my point of view, the distance to you is only 5 light seconds (50% length contraction). So I expect to meet you when 5.77 seconds have elapsed on my clock (5c/.866c) and I expect to have an amount of muons in my box consistent with that time. That’s the same time (and the same amount of muons) as you expected for my clock and my box. So far, no contradiction.

 

Now for the hard part.

I believe your clock is running at 50% the rate of my clock. So if 5.77 seconds elapsed on my clock, only 2.89 seconds will have elapsed on your clock between the time I started monitoring and the time we met. But it was given that 11.55 seconds elapsed on your clock when we met. I’m standing right next to you. I have to see the same number on your clock or there is a paradox. How do I resolve that? Well, you must have started monitoring 17.33 seconds before I started monitoring. Since your clock was running at 50%, 17.33 /2 means 8.67 seconds already elapsed on your clock before I even started my clock. Add 2.89 more seconds while both of us were monitoring and I will expect 11.55 seconds elapsed on your clock when we meet. That eliminates the contradiction. If you’re thinking I invented my answer just for this problem, I didn’t. It’s part of the theory.

 

To Summarize:

From your point of view we both started monitoring our boxes of muons at the same time. From my point of view you started monitoring your muons 17.33 seconds before I started monitoring mine. What is simultaneous to you is not simultaneous to me. That’s how Length Contraction, Time Dilation and Relativity of Simultaneity work together to eliminate any contradiction.

 

Can I show that using actual calculations? Sure. I could post some equations with the right numbers on the other side of the “equals” sign. Would you then be convinced? I doubt it.

 

 

 

Thanks at least you appear to given a comprehensive answer, I don't have time to go through it right now,, but I will later.

esbo, have you read my post earlier in this thread?

I have now but it basically boils do to "Do the simultaneity calculation." and I don't believe that is a good enough answer it is too vague.

You need to highlight the error.

I mean you are basically say there is an error, go find it.

However, my basic question is "where is the error in this?"

So it's your job to find it!! Not mine!!

 

The proposer is deficient in not doing a rigorous analysis. This is the old trick of shifting the burden of proof. If you skip the hard work, it's too easy to come up with outlandish and complicated scenarios and come to any convenient conclusion you wish, and then you leave all the hard work to the debunker. It's a fundamentally dishonest approach. You are not right until proven wrong.

 

 

 

It's also the only way to learn. people doing your work for you doesn't provide the same result.

As I said before, that is basically a cop out answer.

You are basically saying you won't or rather can't find a specific fault in it.

It is you who is using the old trick of telling me to find my own solution.

Nice try but I am not falling for it.

You can basically 'answer' all questions with that kind of response.

And form what I have discovered this is not the first time you have failed to provide and answer which *proves* the proposition wrong.

The burden of that detail is on the proposer who claims relativity is wrong. You don't get a pass because you didn't follow the proper rigor in presenting the problem. Do the simultaneity calculation.

The proposer has in effect provided his proof, you are saying it is wrong, I think the onus is you to prove he is wrong by

say specifically where he is wrong.

It's like in a maths question and you saying he has done his maths wrong, you need to provide a correction to the detail

ie say in which specific line of maths there is an error.

Just saying "you need to check your maths' is a bit of a cop out, I because anyone could say that irregardless of whether

they knew were the error was.

So if anyone can provide that specific detail I would be very grateful grateful.

If they can't I guess I will be forced to look elsewhere.

Though please be aware that special relativity has passed all direct and indirect tests asked of it. Take into accound the domain of validity and experimental errors, there is no reason to doubt special relativity.I doubt he would have disagreed. Do you think he would disagreed, if so why?Not at all, but you have to make sure you have a real challange.

 

Anyway, I wonder now if this thread is diverging from the opening post. Swansont's suggestion that simultaneity, or really the lack of, is the root of the paradox seems very reasonable to me.

But I don't consider that a sufficient answer, he needs to explain precisely how simultaneity is the paradox. indeed you say 'suggests', basically

it all seems to vague to be an adequate answer. More details is needed.

The above is a crackpot website written by a person that is in denial of mainstream physics.

A lot of scientist have been though of as crackpots in their time.

Here is a list of a few of them.

• Arrhenius (ion chemistry)
• Alfven, Hans (galaxy-scale plasma dynamics)
• Baird, John L. (television camera)
• Bakker, Robert (fast, warm-blooded dinosaurs)
• Bardeen & Brattain (transistor)
• Bretz J Harlen (ice age geology)
• Chandrasekhar, Subrahmanyan (black holes in 1930)
• Chladni, Ernst (meteorites in 1800)
• Crick & Watson (DNA)
• Doppler (optical Doppler effect)
• Folk, Robert L. (existence and importance of nanobacteria)
• Galvani (bioelectricity)
• Harvey, William (circulation of blood, 1628)
• Krebs (ATP energy, Krebs cycle)
• Galileo (supported the Copernican viewpoint)
• Gauss, Karl F. (nonEuclidean geometery)
• Binning/Roher/Gimzewski (scanning-tunneling microscope)
• Goddard, Robert (rocket-powered space ships)
• Goethe (Land color theory)
• Gold, Thomas (deep non-biological petroleum deposits)
• Gold, Thomas (deep mine bacteria)
• Lister, J (sterilizing)
• T Maiman (Laser)

• Margulis, Lynn (endosymbiotic organelles)
• Mayer, Julius R. (The Law of Conservation of Energy)
• Marshall, B (ulcers caused by bacteria, helicobacter pylori)
• McClintlock, Barbara (mobile genetic elements, "jumping genes", transposons)
• Newlands, J. (pre-Mendeleev periodic table)
• Nott, J. C. (mosquitos xmit Yellow Fever)
• Nottebohm, F. (neurogenesis: brains can grow neurons)
• Ohm, George S. (Ohm's Law)
• Ovshinsky, Stanford R. (amorphous semiconductor devices)
• Pasteur, Louis (germ theory of disease)
• Prusiner, Stanley (existence of prions, 1982)
• Rous, Peyton (viruses cause cancer)
• Semmelweis, I. (surgeons wash hands, puerperal fever )
• Steen-McIntyre, Virginia (southwest US indians villiage , 300,000BC)
• Tesla, Nikola (Earth electrical resonance, "Schumann" resonance)
• Tesla, Nikola (brushless AC motor)
• J H van't Hoff (molecules are 3D)
• Warren, Warren S (flaw in MRI theory)
• Wegener, Alfred (continental drift)
• Wright, Wilbur & Orville (flying machines)
• Zwicky, Fritz (existence of dark matter, 1933)
• Zweig, George (quark theory)

I never put people down for asking questions, it is a good thing.

Something to be encouraged.

I will always try to answer questions so they can understand them.

I think it is people who lack confidence in their own understanding who seek to put people

down to deter them from asking questions they can't answer.

There has always been a bit of that in science, people do not want to lose their reputation etc..

And even if the crackpots are wrong at least they are provoking discussion.

Remember one thing science constantly does is prove old theories wrong or improve on them.

The mainstream is not always right, but they do fear being proved wrong.

.

Here is just one example of a crackpot who was right, so do not be to quick to putt hem down!!

J Harlen Bretz

You can just imagine the amount of ridicule he had to endure.

obviously time travel is impossible else you could travel back in time and shoot yourself dead.

Loved the bit in the Family Guy video where one oft he Brian's was dead and Brian says shouldn't they all be dead then?

The answer is of course no, if they were from before he died they coudl be alive , there should be no Brians from the future after he was dead.

Brians from the past could have travelled into the future past his death though (if time travel forward is possible) so I guess forward time

travel could be posssible, but not back.

there is a excellent Family Guy episode which includes time travel.

It's really good stuff it goes into the danger of time travel and all that, I can't

remember exactly what happens but they have to be careful not do ore not to do certain stuff.

One of the best episodes I have seen it end up with hundreds of : Brian and Stewie all together from difference times periods

deciding what they need to do!!!

It fact here is the episode here

https://www.youtube.com/watch?v=lNq_t1S3JH0

really good!!

You maybe confusing the issues here.

 

A thought experiment is a hypothetical situation that you study on paper. You then use whatever theory you have at hand to analyse the situation. It can be a useful way to clear up your misunderstandings or indeed point to new physics. Einstein used thought experiments to help him devise special relativity, for example.

 

However, as a hypothetical situation it is not necessarily true that nature will agree with your thought experiment. A theory can only truly be tested against nataure with a real experiment.

 

Of course, lots of though and effort goes into planning and executing a real experiment. Also the analysis of the results and comparing with theory requires lots of effort. But this is not what we mean by "though" in thought experiment.

I don't think a study has to be carried out on paper, in my opinion though can only occur in the mind, paper can be be used to aid memory

but thought occurs only in the mind.

People can make mistakes in their maths and thought can be used to determine a thought has occurred.

I am confident I know in my own mind what though and though experiment mean..

Einstein used thought to make sense of experimental data/results.

Further to SwansonT and ajb - and hoping they/others will correct me if I have this wrong - Special Relativity is entirely mathematically self-consistent and this maths is pretty simple and well agreed. This implies that there is no scenario which can be thought up that can produce a self-contradictory answer. Thought experiments are useful in situations where this is not the case - in other parts of science you can posit a physically realistic scenario within the terms of application of the theory and get silly answers, self-contradictions, or breaches of other physical laws; these "ba d" answers may show a flaw in the theory. However due to the simplicity and rigor of Special Relativity there is no possibility of a sensible scenario, within the bounds of application, which will provide a paradox or a problem. Most problems with SR are due to a mis-understanding of the theory, a mis-application of the rules, or the use of a scenario specifically outside the application of the theory.

Mathematics is derived from thought. #Well agreed' is not the same as proven, and even proven often turns out to not proven in some cases.

Indeed SR itself unproven much of what was thought to be proven.

I wonder how Einstein would have responded to someone saying the maths of classical physical is self-consistent , pretty simple and well agreed?

There seems to be an attitude in this forum that everything is understood and agreed and cannot be challenged.

If it were not for people rebelling against that attitude we would still be living in the dark ages, and indeed some say we still are!!

One experiences time dilation for 10 seconds (Earth time). The other experiences time dilation for 50 years (Earth time). The fact that they don't have the same difference in aging isn't particularly surprising.

But to me it depends on whose perspective you are looking from.

When they are together in space they are in the same inertial frame.

One accelerates off to earth thus he should appear to age slower than the one in space.

You seem to be picking earth as an absolute 0 reference frame, but there is no such thing (apparently).

For example say we to go back to before any of these experiment sstarted and we discovered the twins were born on a different planet

which was moving near the speed of light (with respect to earth) and they then jetted off to earth to big the experiments.

That seems to turn everything on it's head if you see what I mean?

There are two events: the twins separating, and the twins coming back together to compare ages.

 

These two events are separated in spacetime. The longer the path through space you take from one to the other, the shorter your path through time. The shorter your path through space, the longer your path through time.

 

The separation and final comparison both take place at rest with respect to the twin who stays behind. In this frame, the twin never moved and therefore experienced the maximum amount of time.

 

According to this frame, the twin that leaves and returns traveled some distance, and this means he experienced proportionately less time.

 

While the twin is initially traveling, he can say that he is the one at rest and the other twin is moving. At this point, both twins will say that the other has aged less, but this isn't a problem because you can only compare clocks if they are co-located. However, once the twin turns around, he can no longer say that he spent the whole time at rest while the other twin traveled because there is no inertial path that goes from the twins separating through the turnaround point and then to the return where the clocks are compared.

 

To answer your question:

 

If 50 years pass on Earth during which one twin is traveling out and back at 99% of the speed of light, that twin will age 7 years.

 

If, during that time, the other twin takes a ten second trip out and back at 90% of the speed of light, that twin will be about 6 seconds younger than he would have been if he'd stayed on Earth the whole time.

 

So their ages would be, if they started when they were first born, 7 years old and 49 years, 364 days, 23 hours, 59 minutes and 54 seconds, respectively, after 50 years as measured on Earth.

But given an object has no memory of previous accelerations, then the two twins are briefly together in space they are in the same

situation as in the the initial twin paradox proposition where both start on earth, one accelerates way for a period of time and then comes

back being much younger.

So in one analogous situation a twin jets away at high speed and stays very young but in another he remains at almost the same age.

I don't see where anything I said contradicts swansont.

Swanout is saying C is 12ish yet you are saying B, who spent most of time on earth is younger than him.

If you get an answer to the triplets question, what next, ask about quadruplets?

We will cross that bridge when we get to it, this needs answering first.

We have contradictory answers to this one to clear up.

I'm saying it's not worth any effort to analyze the details. It won't show that relativity is wrong.

That sounds disconcerting close to "Sorry I don not understand it well enough to provide a coherent answer"?

It that a fair synopsis?

Either way it's not an answer to the question so not really helpful in answering it.

After just a quick scan I suspect the issue is going to come down to simultaneity. The author has assumed that simultaneity is absolute, and it isn't.

 

 

 

It actually means that it is impossible to say how many muons there really are in

the box at a particular time, because time, length and simultaneity are relative, not absolute.

 

 

 

———

 

If a SR thought experiment hits a contradiction, that contradiction is going to be found in the incorrect way the person solved the problem. The underlying math is not at fault, and a made-up scenario is not a real experiment, so it's not a test of the theory. There is no way for a thought experiment to actually show relativity to be wrong. Only an actual, physical experiment can do that.

But surely some thought is required in determining the experiment?

Or is no thought required in determining the experiment?

Which is the case?

Or is it both or neither?

Are you asking whether, if two twins leave Earth together, one turns around and goes back, then turns back around, catches up to the other and they bo return together, the twin who first turned back will have aged more slowly?

 

If so, then yes.

But surely that contradicts swansont's post?

Adding complexity to the problem will not show any contradictions. At the bottom of it all is some fairly simple math that is internally consistent.

Then you must disagree with delta1212?

Yes or no?

Perhaps you could also have a go at the muon problem where the twins see difference number of muons?

What's the paradox? We already know from the twins' case that there is no paradox.

 

Anyway, you are wrong about twin C. 0.99c is a gamma of 7, so twin C will age a little over 7 years and be a little older than 12 upon returning.

 

You should also be able to conclude that twin B is within 10 seconds of the age of twin A just by inspection.

Now supposing twin C synchronises his clock with B before he returns to earth and just before the 50 years is up

he takes off again to tell B it is now time to come back to earth and they both come back together.

Surely C has aged more slowly that B over this period?

I mean is that not like the original twin paradox experiment but it is C who seems to remain stationary whilst B disappears off at high speed,

thus ageing more slowly?

I found the following on the web, comments welcome!!! http://squishtheory.wordpress.com/about/
The triplets paradox

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