Superconductivity at room temperature??

[ben m]

I should have known that when stating this it will be well above your ability to grasp. I admit that I made a mistake to include acceleration in the symmetry discussion, since this requires Einstein's GR to justify. I just do not have the time to do so and lead us into another topic. Thus, as I have described above, I am asking you to only consider the time of 20 years when the two twins coasted symmetrically relative to one another: During this time as you all admitted, the two twins cannot age relative to one another.

During this time, the twins are in different places; any method they might use to compare their ages will involve a simulteneity-shift. The statement they "cannot age relative to each other" is poorly specified. In fact, both twins (each using his own coordinate system, with himself at rest) will that twin will say the other one is younger than himself.

Please note that Hafele-Keating, whom you accused of fraud, in fact had one clock aboard an accelerating coordinate system, which brought it back to the same location as the rest-clock. With both clocks in the same place, there is no simulteneity-shift term, and the statement "the flying clock is younger" is not coordinate-system dependent.

 

[Ziggurat]

I admit that I made a mistake to include acceleration in the symmetry discussion, since this requires Einstein's GR to justify.

No it doesn't.

You claim that it requires acceleration of the one twin to ensure that this twin is younger. This cannot be proved by using the two postulates of Einstein and the Lorentz transformation.

Sure it can. It's just easier to start with the metric ds² = dr² + (ct)². Just as the Euclidean metric tells us that straight lines are the shortest path between two points, the Minkowski metric tells us that a straight world-line is the longest path between two time-like separated points. So curve the world-line and you make it shorter. And curvature in a world-line is the same thing as acceleration. So unless you want to claim that the metric can't be derived from the Lorentz transforms (and it can be), you don't have a leg to stand on here.

But OK, if acceleration is required, it must mean that the differential ageing only occurs during acceleration, and can thus not be due to the time-dilation formula obtained from Special Relativity.

Also not true.

Look, it's not that hard. And there are direct Euclidean geometry parallels. Consider a triangle, with vertices 1,2, and 3, with 1 and 3 as the corners of the base and 2 as the top. The distance from 1 to 3 along the base (we'll call that path A) is shorter than the distance from 1 to 2 to 3 (we'll call that B). Why aren't they the same distance? Well, path A is straight, and path B is curved (or kinked, if you like). But if I calculate the length of path B, do I need to do anything special about that curvature to figure out its length? No. Does the difference in length reside within the curved section? No. So how can path B be longer due to curvature if the extra distance doesn't reside in the curved part?

That's the logic you're using, johan.

 

[sol invictus]

I admit that I made a mistake to include acceleration in the symmetry discussion, since this requires Einstein's GR to justify.

There must be acceleration if the twins are to rejoin each other, Johan. And it's only when they rejoin that their ages can be unambiguously compared.

Thus, as I have described above, I am asking you to only consider the time of 20 years when the two twins coasted symmetrically relative to one another: During this time as you all admitted, the two twins cannot age relative to one another.

I have admitted no such thing. That statement is true in one set of frames (those in which the motion of the twins is symmetric), but it's false in others.

You claim that it requires acceleration of the one twin to ensure that this twin is younger. This cannot be proved by using the two postulates of Einstein and the Lorentz transformation. But OK, if acceleration is required, it must mean that the differential ageing only occurs during acceleration, and can thus not be due to the time-dilation formula obtained from Special Relativity.

Wrong on all counts.

Regardless, do you now admit that the traveling twin will be younger upon his return?

 

[leonAzul]

Game, set, match.

Thanks!

I must say I am pleasantly surprised to hear you taking it so well.

That was not a congratulations, but rather an invitation to concede gracefully.

 

[ben m]

I think what we are seeing is that Johan understands nothing whatsoever about Special Relativity. He recognizes that there's said to be some sort of dilation-term proportional to gamma or sqrt(1-v^2/c^2). That's it. The rest of the physics is simply unknown. Events, coordinates, actual Lorentz transformations ... he's forgotten them all.

It's bizarre. I can't imagine where one would learn relativity in a way that says "just multiply stuff by gamma"; I can't imagine where one would learn relativity that doesn't precisely forestall Johan's sloppy mistakes. How is it possible to have seen a relativity book at all and make a statement like

I am asking you to only consider the time of 20 years when the two twins coasted symmetrically relative to one another: During this time ... the two twins cannot age relative to one another.

with its (apparently sincere, utterly clueless) request for an absolute comparison of time-data in two different places. This is practically #1 on the list of Common Mistakes When Using Relativity For The First Time.

Dude, what relativity book do you have in front of you? Do you see the Lorentz transformation? Do you see the time-transformation term? Do you see the "vx/c" term? That term is important. Why are you dropping it? (Oh, right: because you chose to use words rather than math.)

With that term, the Lorentz transformations (a) preserve Einstein's two postulates and (b) predict the age-difference in the twin-paradox/Hafele-Keating/muon-storage-ring experiments. As everyone has known for a long time.

What do we call Einstein's 1905 transformations if we forget the vx/c term? Let's call it the Prins-Dingle transformation. The Prins-Dingle transformation violates Einstein's two postulates. Johan, your analysis of the flaws in Prins-Dingle transform are actually correct. (Too bad you thought you were criticizing the Lorentz transform.)

 

[leonAzul]

I I admit that I made a mistake to include acceleration in the symmetry discussion, since this requires Einstein's GR to justify.

That is akin to arriving at centre court with no strings on your racket.

Game, set, match. Please concede the loss and learn from it. That's not even wrong. That's not even playing.

You claim that it requires acceleration of the one twin to ensure that this twin is younger..

Which part of asymmetrical acceleration don't you understand?

 

[The Don]

You claim that it requires acceleration of the one twin to ensure that this twin is younger. This cannot be proved by using the two postulates of Einstein and the Lorentz transformation. But OK, if acceleration is required, it must mean that the differential ageing only occurs during acceleration, and can thus not be due to the time-dilation formula obtained from Special Relativity.

Good night for now.

My bolding......

With respect to the bolded bit..... no

 

[johanfprins]

I have read the posts after my last post. It is the usual nonsense that Sol, Zig, Ben and their choir is emanating without first putting their brains into gear.

The ONLY space-time within which time can change from position to position and from one reference frame to another is a curved space-time which is curved owing to gravity around mass. In this case, both the time rate and light speed change in unison. That is why they both become zero at the event horizon of a black hole.

When you extrapolate to zero gravity with no curvature, you find that the speed of light increases to a maximum value c and does not change from point to point or inertial reference fame to inertial reference frame anymore. This means that both the time rate and light speed are now maximum constants and that both do not change with position or reference frames. Thus, it is impossible for two twins to age differentially within their separate inertial reference frames since the time rate within these inertial reference fames are identical. If they were not, then light speed should also have been different.

You argue that the ages of the twins can only be compared once they are brought back together, and that the time difference can then be calculated in terms of the time dilation formula of SR. However, the Lorentz transformation has not been derived for acceleration and deceleration at all, so in terms of SR, one cannot bring the twins back together until the Lorentz transformation has been extended to include acceleration.

Furthermore, in terms of Einstein's postulates and the Lorentz transformation you do not have to bring them together to compare their ages, since when they travel at a speed v relative to one another, the time rate within each inertial reference frame is exactly the same (as also mandated by Einstein's first postulate). This demands that when the clock with one twin indicates he has aged 10 years he will know that at that same instant in time his brother has also ony aged 10 years.

The only reason given why they must be brought together, and it is the wrong reason, is to argue that they follow different paths through four-dimensional space time within which time changes with position and therefore the paths will give different ages. This is of course unadulaterated nonsense when using SR since such different paths are only possible within curved space time. The Minkowski so-called space time for SR is NOT curved.

Both twins travel within their respective reference frames parallel to the time axis since both twins are stationary within their respective reference frames. To conclude that the apparrant path that each twin sees the other twin following (as viewed from their own inertial reference frames) are real paths through an actual space-time, is just plain wrong.

Now I have wasted too much of my valuable time on this thread arguing with people who cannot follow any physics-logic unless they can look it up like parrots in a text book. I am tired and my health is starting to suffer. I also have far better things to do: One of my motto's has become the following: "do not argue with clever idiots".

Thus I bid you all farewell so that I can use my time doing something more useful.

Farewell.

 

[ben m]

Furthermore, in terms of Einstein's postulates and the Lorentz transformation you do not have to bring them together to compare their ages, since when they travel at a speed v relative to one another, the time rate within each inertial reference frame is exactly the same (as also mandated by Einstein's first postulate). This demands that when the clock with one twin indicates he has aged 10 years he will know that at that same instant in time his brother has also ony aged 10 years.

Nope. Wrong. Write down 4-coordinates and do the transformations. Don't forget the vx/c terms this time.

ETA: of course you won't. Fine, I'll do it. Using twin #1's clocks and rulers (x,t), I will label three spacetime coordinates. We'll make their relative velocities 0.866c, so gamma=2.

A: twins separate at birth. x=0,t=0.
B: Twin #1 celebrates 10th birthday. x=0,t=10.
C: This is where Twin #2 is at the moment of Twin #1's 10th birthday. x=8.66, t=10.

We Lorentz transform all of those coordinates, using u=0.866, to get into Twin #2's coordinate system x',t'.

A: x'=0,t'=0.
B: x' = 17.32, t'=20.
C: x' = 0, t' = 5.

When Twin 1 is at B, celebrating his 10th birthday, he wants to know Twin 2's age "right now"; right now twin 2 is at C. But Twin 2, as we see in the transformed coordinates, arrives at C on his own 5th birthday (t'=5). So Twin 1, on arriving at B, says "right now is my own 10th birthday, but right now my twin is at C celebrating his 5th."

When Twin 2 is celebrating his 20th birthday, he wants to know Twin 1's age "right now"; according to the x' t' simulteneity, right now twin 1 is at at B. But Twin 1, as we see, arrives at B on his own 10th birthday. Twin 2, arriving at his own 20th birthday party (whose coordinates are x'=0,t'=20), says, "Right now is my own 20th birthday, but right now my twin is at B celebrating his 10th."

So each twin (correctly) says that the other twin is 1/2 of his own age.

Confusing, right? It would be confusing if you weren't actually doing the Lorentz transformations and keeping careful track of coordinates. Boy, I'm glad that no actual physicist ever tries to do that.

 

[Ziggurat]

The ONLY space-time within which time can change from position to position and from one reference frame to another is a curved space-time which is curved owing to gravity around mass.

Huh. And here I thought that the Lorentz transformations included an equation for transforming time:

Oh, look at that: the very first equation shows that time changes for different reference frames, AND the change depends upon position. Wow. That's an accomplishment: NOTHING you said is even remotely true.

You argue that the ages of the twins can only be compared once they are brought back together, and that the time difference can then be calculated in terms of the time dilation formula of SR. However, the Lorentz transformation has not been derived for acceleration and deceleration at all, so in terms of SR, one cannot bring the twins back together until the Lorentz transformation has been extended to include acceleration.

Not true. And not relevant. And you don't even need the Lorentz transformations to do the problem, you can do it easily (including with acceleration) by going straight to the Minkowski metric.

Furthermore, in terms of Einstein's postulates and the Lorentz transformation you do not have to bring them together to compare their ages

True, but if they don't come together, then your comparison will be reference-frame-dependent, since simultaneity for separated events is relative. If they come back together, then simultaneity at their meeting becomes invariant.

The Minkowski so-called space time for SR is NOT curved.

Well, duh. Nobody suggested it was.

Both twins travel within their respective reference frames parallel to the time axis since both twins are stationary within their respective reference frames.

But only one reference frame is inertial.

To conclude that the apparrant path that each twin sees the other twin following (as viewed from their own inertial reference frames) are real paths through an actual space-time, is just plain wrong.

Not at all.

But let's actually consider for a moment what each twin would actually see (which, I must remind you, is not the same thing as what they would observe). For the earth-bound twin, they will see the traveling twin's clock moving slower on the outbound journey both as a result of time dilation and Doppler shift. When they turn around and come back, the clock will be slowed by time dilation but sped up by Doppler shift. But since it takes time for light from the traveling twin to get back to earth, the earthbound twin will not see this sped-up clock until more than halfway through the traveling twin's journey. So they see the Doppler shift slow things down for more than half the time, and speed things up for less than half the time.

But what about the traveling twin? Well, same deal: they always see the earth-bound twin's clock slowed down by the same amount from time dilation, but as soon as they turn around, the Doppler shift changes. They don't have to wait for the Doppler shift to change. So they see the Doppler shift slow things down for half the journey, and speed things up for half the journey. So in terms of what they see, the symmetry is obviously broken. The Doppler shift effect will actually outweigh the time dilation effect, and the traveling twin will see the earthbound twin get older by the time he returns.

Now I have wasted too much of my valuable time on this thread arguing with people who cannot follow any physics-logic unless they can look it up like parrots in a text book.

Don't lie to us. Your time isn't valuable.

I am tired and my health is starting to suffer.

And your memory too.

I also have far better things to do: One of my motto's has become the following: "do not argue with clever idiots".

After more than 70 pages, you've finally decided it's not worth arguing with us? If we're so stupid, why did it take you so long to clue in?

Thus I bid you all farewell so that I can use my time doing something more useful.

On that point I agree: you're far better off spending what little time you have left enjoying the company of your family than trying to advance crackpot nonsense.

Say hi to your psychic sister for me!

 

[ben m]

Of course, when Johan says he has "more important things to do", he means he's going back to talk-polywell where he's having the exact same argument. With the same insults and everything.

You see how arrogant you are. I know this wrong reasoning. So why are you posting it as if you want to teach me something. Your knowledge of physics is so rudimentary compared o mine that you are only making an ------- of yourself.

http://talk-polywell.org/bb/viewtopic.php?p=77430&sid=f5782d8e5726315337e17da85102694e#77430

Time well spent there, Johan.

 

[sol invictus]

Thus I bid you all farewell so that I can use my time doing something more useful.

Farewell.

Bravo! I've been urging you to take that decision for a long time now. I hope you stick with it.

 

[Reality Check]

All stationary clocks keep the same time rate and the clocks that have been flown around the world remained stationary with respect to the aeroplane. Thus if Hafele and Keating did, indeed measure what they claim to have measured, it will mean then STR must be wrong. On the other hand, if STR is not wrong, then they could only have found the results that they found by having fudged their results.

This post reveals your continued ignorance of the Hafele and Keating experiment. All stationary clocks keep the same time rate and the clocks that were flown around the world moved eye-poppi!) with respect to the clocks that were left on the ground.
It was the clocks on the plane that were compared to the clocks on the ground. The results agreed with what SR and GR predicted. The results were confirmed in later experiments.

And one more time with the insulting accusation that every scientist that has done this experiment fudged the results (Hafele, Keating and many other scientists).

 

[D'rok]

Bump. I miss this thread so much.

 

[The Man]

As a lurker on this thread I would just like to thank everyone for their involvement (yes even johanfprins) as I have found it very informative.

 

[!Kaggen]

Its a pleasure

 

[Skwinty]

I don"t believe that these are the last words from Johan.