TWIN PARADOX IN EINSTEIN'S 1905 PAPER

The twin paradox has a simpler (one way) version in Einstein's 1905 paper:

http://www.fourmilab.ch/etexts/einstein/specrel/www/
ON THE ECTRODYNAMICS OF MOVING BODIES, A. Einstein, 1905: "From this there ensues the following peculiar consequence. If at the points A and B of K there are stationary clocks which, viewed in the stationary system, are synchronous; and if the clock at A is moved with the velocity v along the line AB to B, then on its arrival at B the two clocks no longer synchronize, but the clock moved from A to B lags behind the other which has remained at B by tv^2/2c^2 (up to magnitudes of fourth and higher order), t being the time occupied in the journey from A to B."

http://blog.hasslberger.com/Dingle_S...Crossroads.pdf
SCIENCE AT THE CROSSROADS, Herbert Dingle, p.27: "According to the special relativity theory, as expounded by Einstein in his original paper, two similar, regularly-running clocks, A and B, in uniform relative motion, must work at different rates. (...) How is the slower-working clock distinguished?"

Dingle's question is rhetorical - the slower-working clock cannot be distinguished on the basis of Einstein's 1905 postulates alone. The postulates entail that, as judged from the respective system, either clock runs slower than the other. That is, for an observer in the moving clock's system, the stationary clock at B lags behind the moving clock; for a stationary observer, the moving clock lags behind the stationary clock at B.

So Einstein's famous conclusions that made him a superstar, "moving clocks run slow" and "travel into the future is possible", are based on two flaws. Initially Einstein advanced his false constant-speed-of-light postulate, which allowed him to validly deduce that:

moving clocks run slow, as judged from the stationary system.

Then he illegitimately dropped the second part of the above conclusion and informed the gullible world that:

moving clocks run slow, that is, travel into the future is possible.

Pentcho Valev

https://www.youtube.com/watch?v=-O8lBIcHre0
Brian Cox (03:56): "Time travel into the future is possible".

Comment:

Pentcho Valev 3 months ago:
Jim Al-Khalili is no time traveller in this experiment - the postulates of special relativity do NOT entail time travel into the future. The confusion goes back to 1905 when Einstein informed the gullible world that, although time dilation is symmetrical (either observer sees the other's clock running slow - this is what validly follows from the two postulates), it is still asymmetrical - the stationary clock runs faster than the moving one (this does not follow at all from the postulates):

http://www.fourmilab.ch/etexts/einstein/specrel/www/
ON THE ELECTRODYNAMICS OF MOVING BODIES, A. Einstein, 1905: "From this there ensues the following peculiar consequence. If at the points A and B of K there are stationary clocks which, viewed in the stationary system, are synchronous; and if the clock at A is moved with the velocity v along the line AB to B, then on its arrival at B the two clocks no longer synchronize, but the clock moved from A to B lags behind the other which has remained at B by tv^2/2c^2 (up to magnitudes of fourth and higher order), t being the time occupied in the journey from A to B."

This is tantamount to saying that, although elephants are unable to fly, they can still do so by just flapping their ears. Yet the breathtaking impliciations of Einstein's blatant hoax (time travel into the future etc) enchanted the public:

http://plus.maths.org/issue37/featur...ein/index.html
John Barrow FRS: "Einstein restored faith in the unintelligibility of science. Everyone knew that Einstein had done something important in 1905 (and again in 1915) but almost nobody could tell you exactly what it was. When Einstein was interviewed for a Dutch newspaper in 1921, he attributed his mass appeal to the mystery of his work for the ordinary person: "Does it make a silly impression on me, here and yonder, about my theories of which they cannot understand a word? I think it is funny and also interesting to observe. I am sure that it is the mystery of non-understanding that appeals to them...it impresses them, it has the colour and the appeal of the mysterious." Relativity was a fashionable notion. It promised to sweep away old absolutist notions and refurbish science with modern ideas. In art and literature too, revolutionary changes were doing away with old conventions and standards. All things were being made new. Einstein's relativity suited the mood. Nobody got very excited about Einstein's brownian motion or his photoelectric effect but relativity promised to turn the world inside out."
_________________________________________________
[end of quotation]

Pentcho Valev

Einsteiniana: The youthfulness of the travelling twin is due to the turn-around acceleration, but at the same time it is not due to the turn-around acceleration:

http://en.wikisource.org/wiki/Dialog...f_rela tivity
Dialog about Objections against the Theory of Relativity, 1918, Albert Einstein: "During the partial processes 2 and 4 the clock U1, going at a velocity v, runs indeed at a slower pace than the resting clock U2. However, this is more than compensated by a faster pace of U1 during partial process 3. According to the general theory of relativity, a clock will go faster the higher the gravitational potential of the location where it is located, and during partial process 3 U2 happens to be located at a higher gravitational potential than U1. The calculation shows that this speeding ahead constitutes exactly twice as much as the lagging behind during the partial processes 2 and 4."

http://www.pitt.edu/~jdnorton/teachi...yon/index.html
John Norton: "Then, at the end of the outward leg, the traveler abruptly changes motion, accelerating sharply to adopt a new inertial motion directed back to earth. What comes now is the key part of the analysis. The effect of the change of motion is to alter completely the traveler's judgment of simultaneity. The traveler's hypersurfaces of simultaneity now flip up dramatically. Moments after the turn-around, when the travelers clock reads just after 2 days, the traveler will judge the stay-at-home twin's clock to read just after 7 days. That is, the traveler will judge the stay-at-home twin's clock to have jumped suddenly from reading 1 day to reading 7 days. This huge jump puts the stay-at-home twin's clock so far ahead of the traveler's that it is now possible for the stay-at-home twin's clock to be ahead of the travelers when they reunite."

http://www.fnal.gov/pub/today/archiv...lReadMore.html
Don Lincoln: "Some readers, probably including some of my doctoral-holding colleagues at Fermilab, will claim that the difference between the two twins is that one of the two has experienced an acceleration. (After all, that's how he slowed down and reversed direction.) However, the relativistic equations don't include that acceleration phase; they include just the coasting time at high velocity."

http://www.damtp.cam.ac.uk/research/...tivity2010.pdf
Gary W. Gibbons FRS: "In other words, by simply staying at home Jack has aged relative to Jill. There is no paradox because the lives of the twins are not strictly symmetrical. This might lead one to suspect that the accelerations suffered by Jill might be responsible for the effect. However this is simply not plausible because using identical accelerating phases of her trip, she could have travelled twice as far. This would give twice the amount of time gained."

http://www.ferovanemocnice.cz/images...es/f_pic31.jpg

http://ebooks.adelaide.edu.au/o/orwe...hapter2.9.html
"Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously, and accepting both of them. The Party intellectual knows in which direction his memories must be altered; he therefore knows that he is playing tricks with reality; but by the exercise of doublethink he also satisfies himself that reality is not violated. The process has to be conscious, or it would not be carried out with sufficient precision, but it also has to be unconscious, or it would bring with it a feeling of falsity and hence of guilt. Doublethink lies at the very heart of Ingsoc, since the essential act of the Party is to use conscious deception while retaining the firmness of purpose that goes with complete honesty. To tell deliberate lies while genuinely believing in them, to forget any fact that has become inconvenient, and then, when it becomes necessary again, to draw it back from oblivion for just so long as it is needed, to deny the existence of objective reality and all the while to take account of the reality which one denies - all this is indispensably necessary. (...) It need hardly be said that the subtlest practitioners of doublethink are those who invented doublethink and know that it is a vast system of mental cheating. In our society, those who have the best knowledge of what is happening are also those who are furthest from seeing the world as it is. In general, the greater the understanding, the greater the delusion ; the more intelligent, the less sane.."

Pentcho Valev

Einstein's 1905 postulates entail that, as shown in the picture below, a single MOVING CLOCK SHOWS LESS TIME ELAPSED than multiple stationary clocks as it passes them consecutively. However, if the single clock is stationary and the multiple clocks moving, Einstein's postulates entail that this time the STATIONARY CLOCK SHOWS LESS TIME ELAPSED than the multiple moving clocks. Clearly Einstein's 1905 postulates do not entail that moving clocks run more slowly than stationary clocks, or that the travelling twin will return younger than his stationary brother:

http://www.pitt.edu/~jdnorton/teachi...ty/index..html
http://www.pitt.edu/~jdnorton/teachi...y/Clocks_1.png

Pentcho Valev

The youthfulness of the travelling twin is due to the turn-around acceleration again:

https://www.youtube.com/watch?v=bjHLboK2M1g
Eugene Khutoryansky: Twin Paradox in General Relativity

There are twin paradox scenarios without any acceleration but Eugene Khutoryansky couldn't care less - he is paid to teach that the acceleration is crucial:

http://sciencechatforum.com/viewtopic.php?f=84&t=26847
Don Lincoln: "A common explanation of this paradox is that the travelling twin experienced acceleration to slow down and reverse velocity. While it is clearly true that a single person must experience this acceleration, you can show that the acceleration is not crucial. What is crucial is that the travelling twin experienced time in two reference frames, while the homebody experienced time in one. We can demonstrate this by a modification of the problem. In the modification, there is still a homebody and a person travelling to a distant star. The modification is that there is a third person even farther away than the distant star. This person travels at the same speed as the original traveler, but in the opposite direction. The third person's trajectory is timed so that both of them pass the distant star at the same time. As the two travelers pass, the Earthbound person reads the clock of the outbound traveler. He then adds the time he experiences travelling from the distant star to Earth to the duration experienced by the outbound person. The sum of these times is the transit time. Note that no acceleration occurs in this problem...just three people experiencing relative inertial motion."

http://www.people.fas.harvard.edu/~djmorin/chap11.pdf
Introduction to Classical Mechanics With Problems and Solutions, David Morin, Cambridge University Press, Chapter 11, p. 44: "Modified twin paradox *** Consider the following variation of the twin paradox. A, B, and C each have a clock. In A's reference frame, B flies past A with speed v to the right. When B passes A, they both set their clocks to zero. Also, in A's reference frame, C starts far to the right and moves to the left with speed v. When B and C pass each other, C sets his clock to read the same as B's. Finally, when C passes A, they compare the readings on their clocks."

Pentcho Valev

The role of the turnaround acceleration in Einstein's schizophrenic world:

http://en.wikipedia.org/wiki/Twin_paradox
"In other words, neither Einstein nor Langevin saw the story of the twins as constituting a challenge to the self-consistency of relativistic physics.. (...) Although some texts assign a crucial role to the acceleration of the travelling twin at the time of the turnaround, others note that the effect also arises if one imagines separate outward-going and inward-coming travellers, who pass each other and synchronize their clocks at the point corresponding to "turnaround" of a single traveller. In this version, acceleration plays no direct role; "the issue is how long the world-lines are, not how bent". (...) During the turnaround, the traveling twin is in an accelerated reference frame. According to the equivalence principle, the traveling twin may analyze the turnaround phase as if the stay-at-home twin were freely falling in a gravitational field and as if the traveling twin were stationary. A 1918 paper by Einstein presents a conceptual sketch of the idea."

http://farm5.staticflickr.com/4010/4...22552b04_z.jpg

http://ebooks.adelaide.edu.au/o/orwe...hapter2.9.html
"Doublethink means the power of holding two contradictory beliefs in one's mind simultaneously, and accepting both of them. The Party intellectual knows in which direction his memories must be altered; he therefore knows that he is playing tricks with reality; but by the exercise of doublethink he also satisfies himself that reality is not violated. The process has to be conscious, or it would not be carried out with sufficient precision, but it also has to be unconscious, or it would bring with it a feeling of falsity and hence of guilt. Doublethink lies at the very heart of Ingsoc, since the essential act of the Party is to use conscious deception while retaining the firmness of purpose that goes with complete honesty. To tell deliberate lies while genuinely believing in them, to forget any fact that has become inconvenient, and then, when it becomes necessary again, to draw it back from oblivion for just so long as it is needed, to deny the existence of objective reality and all the while to take account of the reality which one denies - all this is indispensably necessary. (...) It need hardly be said that the subtlest practitioners of doublethink are those who invented doublethink and know that it is a vast system of mental cheating. In our society, those who have the best knowledge of what is happening are also those who are furthest from seeing the world as it is. In general, the greater the understanding, the greater the delusion ; the more intelligent, the less sane.." x

Pentcho Valev