Idiocy Called Twin Paradox

[Pentcho Valev]

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. 14: "Twin A stays on the earth, while twin B flies quickly to a distant star and back. (...) For the entire outward and return parts of the trip, B does observe A's clock running slow, but enough strangeness occurs during the turning-around period to make A end up older. Note, however, that a discussion of acceleration is not required to quantitatively understand the paradox..."

This is idiotic isn't it? The traveling twin turns around, and this act of his miraculously makes the distant stationary twin on the Earth older. The video below elaborates on the idiocy. During the very brief moment when the traveling twin turns around, he experiences acceleration or "gravitational field" (the turn-around and the acceleration are absent in some twin-paradox scenarios - there is no "gravitational field"). Einsteinians explain that the traveling twin "will BELIEVE that this gravitational field exists throughout all of space, and that this gravitational field is causing the Earth and the rest of the universe to accelerate towards him". And then a second belief: "Therefore, Adam will BELIEVE that the gravitational field is causing time on Earth to flow much faster than time on his ship". In short, the solution of the twin paradox is based on the beliefs of the traveling twin during the turning-around period, beliefs which are obviously false but are nevertheless ascribed to the traveling twin by Einsteinians:

"For Adam to return back to Earth, he will eventually need to fire his rockets to turn around. When he fires his rockets, Adam will still continue to think that his spaceship is standing still. However, in order to believe that his spaceship is standing still, he needs to also believe that there is now a gravitational field present that is cancelling out the force from his rockets. Adam will believe that this gravitational field exists throughout all of space, and that this gravitational field is causing the Earth and the rest of the universe to accelerate towards him. (...) Therefore, Adam will believe that the gravitational field is causing time on Earth to flow much faster than time on his ship. It is only during the very brief moment when Adam is firing his rockets to turn around that he believes this external gravitational field is present. For the remainder of his trip after he turns his rockets off, Adam will again view time on Earth as moving slowly. Nevertheless, during the very brief moments when he fires his engines, he sees time on Earth flowing so extremely fast that this far more than compensates for the fact that he sees time on Earth flowing slowly during the rest of his journey. This is why Adam will believe that more time has passed for Sarah than for him when he returns."

This idiotic "solution" of the twin paradox was fabricated by Einstein in 1918 ("A homogenous gravitational field appears" which can only reach the Earth in the beliefs of the traveling twin):

http://sciliterature.50webs.com/Dialog.htm
Albert Einstein 1918: "A homogenous gravitational field appears, that is directed towards the positive x-axis. Clock U1 is accelerated in the direction of the positive x-axis until it has reached the velocity v, then the gravitational field disappears again. An external force, acting upon U2 in the negative direction of the x-axis prevents U2 from being set in motion by the gravitational field. (...) 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."

Pentcho Valev

[Sam Wormley]

Hey Pentcho, you should take the time to learn the the basic
principles involved in the twin paradox.

http://www.phys.vt.edu/~takeuchi/relativity/notes/section15.html
Loading Image...

[Y.Porat]

Post by Sam Wormley
Hey Pentcho, you should take the time to learn the the basic
principles involved in the twin paradox.

http://www.phys.vt.edu/~takeuchi/relativity/notes/section15.html
http://www.phys.vt.edu/~takeuchi/relativity/notes/twin.gif

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======================
imbecile parrot !!
a human being is much more complicated
for you to understand it !!!

Y.Porat
============================

[john]

"The traveler's hypersurfaces of simultaneity now flip up dramatically."
Don't you love physicists' nonsense-speak?

[HVAC]

john
"The traveler's hypersurfaces of simultaneity now flip up dramatically."
Don't you love physicists' nonsense-speak?
-----------

The ability to turn a phrase is key

[Pentcho Valev]

Here is the original idiocy:

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."

Why is the moving clock slow and the stationary one fast? No such asymmetry follows from Einstein's 1905 postulates. What validly follows is that the moving clock is slow as judged from the stationary system, and the stationary clock is slow as judged from the moving system. Einstein's conclusion above (the moving clock "lags behind" the stationary one) is invalid - it does not follow from the postulates. So even if Einstein's 1905 postulates were true (actually the second one is false), there would be no difference in the clocks' readings.

Pentcho Valev

[Sam Wormley]

Post by Pentcho Valev
Why is the moving clock slow and the stationary one fast? No such asymmetry follows from Einstein's 1905 postulates. What validly follows is that the moving clock is slow as judged from the stationary system, and the stationary clock is slow as judged from the moving system. Einstein's conclusion above (the moving clock "lags behind" the stationary one) is invalid - it does not follow from the postulates. So even if Einstein's 1905 postulates were true (actually the second one is false), there would be no difference in the clocks' readings.
Pentcho Valev

Neither of Einstein's postulate are false.

An axiom or postulate as defined in classic philosophy, is a
statement (in mathematics often shown in symbolic form) that is
so evident or well-established, that it is accepted without
controversy or question. Thus, the axiom can be used as the premise
or starting point for further reasoning or arguments, usually in
logic or in mathematics.

As used in modern logic, an axiom is simply a premise or starting
point for reasoning. Whether it is meaningful (and, if so, what
it means) for an axiom, or any mathematical statement, to be "true"
is a central question in the philosophy of mathematics, with modern
mathematicians holding a multitude of different opinions.

Physics FAQ | Tests of Einstein's two Postulates
http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#Tests_of_Einsteins_two_postulates

This is posted for the benefit of Pentcho Valev. Many enlightenment
brighten your day.

[Pentcho Valev]

Einstein was a subtle practitioner of doublethink - he was able to defend both thesis and antithesis with the same conviction and without any sign of remorse. So before the advent of Einstein's general relativity, the traveling-twin-is-younger tale was more than vulnerable in an analysis taking into account only the valid conclusions from Einstein's 1905 postulates. The youthfulness of the traveling twin was totally unjustifiable - the stationary twin sees his brother's clock running slow, the traveling twin sees his brother's clock running slow, and "the sudden change of direction" involving acceleration is immaterial, as Einstein had implicitly assumed in his 1905 paper and explicitly announced in 1911:

http://einsteinpapers.press.princeton.edu/vol3-trans/368
Einstein 1911: "The clock runs slower if it is in uniform motion, but if it undergoes a change of direction as a result of a jolt, then the theory of relativity does not tell us what happens. The sudden change of direction might produce a sudden change in the position of the hands of the clock. However, the longer the clock is moving rectilinearly and uniformly with a given speed in a forward motion, i.e., the larger the dimensions of the polygon, the smaller must be the effect of such a hypothetical sudden change."

In 1918 "the sudden change of direction" involving acceleration, which had been immaterial a couple of years before, became crucial:

http://sciliterature.50webs.com/Dialog.htm
Einstein 1918: "A homogenous gravitational field appears, that is directed towards the positive x-axis. Clock U1 is accelerated in the direction of the positive x-axis until it has reached the velocity v, then the gravitational field disappears again. An external force, acting upon U2 in the negative direction of the x-axis prevents U2 from being set in motion by the gravitational field. (...) 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."

Today's Einsteinians are all doublethinkers but not as subtle as Einstein. They accept both thesis and antithesis - the acceleration is immaterial and crucial at the same time - but in public they defend either one or the other - never both. So half of the Einsteinians teach that "the sudden change of direction" involving acceleration is immaterial, the other half teach that it is crucial:

http://www.pbs.org/wgbh/nova/blogs/physics/2015/04/physics-needs-philosophy/
Tim Maudlin: "But even the great Richard Feynman did not always get the explanation right. In "The Feynman Lectures on Physics," he attributes the difference in ages to the acceleration one twin experiences: the twin who accelerates ends up younger. But it is easy to describe cases where the opposite is true, and even cases where neither twin accelerates but they end up different ages."

http://www.fnal.gov/pub/today/archive/archive_2014/today14-05-02_NutshellReadMore.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/gr/members/gibbons/gwgPartI_SpecialRelativity2010.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.people.fas.harvard.edu/~djmorin/chap11.pdf
Introduction to Classical Mechanics With Problems and Solutions, David Morin, Cambridge University Press, Chapter 11, p. 14: "Twin A stays on the earth, while twin B flies quickly to a distant star and back. (...) For the entire outward and return parts of the trip, B does observe A's clock running slow, but enough strangeness occurs during the turning-around period to make A end up older."

http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/spacetime_tachyon/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."

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Pentcho Valev

[Sam Wormley]

Post by Pentcho Valev
So before the advent of Einstein's general relativity, the traveling-twin-is-younger tale was more than vulnerable in an analysis taking into account only the valid conclusions from Einstein's 1905 postulates.

One doesn't need general relativity to understand the twin paradox.

Hey Pentcho, you should take the time to learn the the basic
principles involved in the twin paradox.

Post by Pentcho Valev
http://www.phys.vt.edu/~takeuchi/relativity/notes/section15.html
http://www.phys.vt.edu/~takeuchi/relativity/notes/twin.gif

[hanson]

Post by Pentcho Valev
So before the advent of Einstein's general relativity,
the traveling-twin-is-younger tale was more than
vulnerable in an analysis taking into account only
the valid conclusions from Einstein's 1905 postulates.

[..] understand the ....
<http://tinyurl.com/Tears-for-Einsteins-Misery>
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