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Einstein's Relativity Does Not Predict Time Travel



 
 
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  #1  
Old February 23rd 19, 07:34 PM posted to sci.astro
Pentcho Valev
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Default Einstein's Relativity Does Not Predict Time Travel

In 1905 Einstein derived, from his two postulates, the conclusion "the clock moved from A to B lags behind the other which has remained at B":

Albert Einstein, On the Electrodynamics of Moving Bodies, 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://www.fourmilab.ch/etexts/einstein/specrel/www/

The conclusion was non sequitur - it didn't follow from Einstein's 1905 postulates. In other words, the argument extracting the conclusion from the postulates was INVALID.

A VALID argument did exist, and if Einstein had used it, he would have deduced the following two conclusions from the postulates:

Conclusion 1: The clock moved from A to B lags behind the other which has remained at B, as judged from the stationary system.

Conclusion 2: The clock which has remained at B lags behind the clock moved from A to B, as judged from the moving system.

Conclusions 1 and 2, in their combination, give no prediction for the readings of the two clocks as they meet at B. That is, although conclusions 1 and 2 are logically correct (do follow from the postulates), their combination amounts to nonsense. Reductio ad absurdum par excellence: the postulates entail absurdity which means that at least one of them is false. If Einstein had been honest, he would have identified the false postulate ("the speed of light is constant") and abandoned his theory immediately.

The INVALIDLY deduced conclusion

"the clock moved from A to B lags behind the other which has remained at B"

provides a falsifiable (in principle) prediction. This implies that, if the invalidity is ignored, there is no apparent reason to abandon the theory "immediately" - the author is fully justified to present it to the scientific community. So Einstein's sleight of hand (invalid deduction) saved special relativity in 1905.

The famous "travel into the future" is a direct implication of the INVALIDLY deduced conclusion - the slowness of the moving clock means that its (moving) owner can remain virtually unchanged while sixty million years are passing for the stationary system:

Thibault Damour: "The paradigm of the special relativistic upheaval of the usual concept of time is the twin paradox. Let us emphasize that this striking example of time dilation proves that time travel (towards the future) is possible. As a gedanken experiment (if we neglect practicalities such as the technology needed for reaching velocities comparable to the velocity of light, the cost of the fuel and the capacity of the traveller to sustain high accelerations), it shows that a sentient being can jump, "within a minute" (of his experienced time) arbitrarily far in the future, say sixty million years ahead, and see, and be part of, what (will) happen then on Earth. This is a clear way of realizing that the future "already exists" (as we can experience it "in a minute")." http://www.bourbaphy.fr/damourtemps.pdf

Pentcho Valev
  #2  
Old February 23rd 19, 10:13 PM posted to sci.astro
Pentcho Valev
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Default Einstein's Relativity Does Not Predict Time Travel

Einstein's 1905 INVALIDLY deduced conclusion

"the clock moved from A to B lags behind the other which has remained at B" x

implies that time ticks SLOWER for the moving observer. This invalidity is what today's Einsteinians teach:

Brian Greene: "If you're moving relative to somebody else, time for you slows down." https://m.youtube.com/watch?v=QnmnLmwBmfE

Brian Cox (2:25): "Moving clocks run slowly" https://www.youtube.com/watch?v=-O8lBIcHre0

John Gribbin: "Einstein's special theory of relativity tells us how the Universe looks to an observer moving at a steady speed. Because the speed of light is the same for all such observers, moving clocks run slow..." http://www.newscientist.com/article/...lativity..html

Neil deGrasse Tyson: "We have ways of moving into the future. That is to have time tick more slowly for you than others, who you return to later on. We've known that since 1905, Einstein's special theory of relativity, which gives the precise prescription for how time would slow down for you if you are set into motion." http://abcnews.go.com/Entertainment/...ry?id=32191481

Jim Al-Khalili: "And, the faster you move and the longer you move at that speed, the slower your clock ticks, including your own internal biological clock, and so the slower you age - by tiny, tiny fractions of a second of course." http://www.jimal-khalili.com/blogs/2...m-with-the-app

A conclusion VALIDLY deducible from Einstein's postulates (that Einstein failed to deduce in 1905) is:

"The clock which has remained at B lags behind the clock moved from A to B, as observed from the moving system."

This conclusion implies that time ticks FASTER for the moving observer. No one teaches validity. Only two exceptions:

David Morin, Introduction to Classical Mechanics With Problems and Solutions, 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..." http://www.people.fas.harvard.edu/~djmorin/chap11.pdf

"The situation is that a man sets off in a rocket travelling at high speed away from Earth, whilst his twin brother stays on Earth. [...] ...the twin in the spaceship considers himself to be the stationary twin, and therefore as he looks back towards Earth he sees his brother ageing more slowly than himself." http://topquark.hubpages.com/hub/Twin-Paradox

Pentcho Valev
  #3  
Old February 24th 19, 08:19 AM posted to sci.astro
Pentcho Valev
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Default Einstein's Relativity Does Not Predict Time Travel

Post-sanity (Einsteinian) science:

"I'm Brian Greene, professor of physics and mathematics at Columbia University and co-founder of the World Science Festival. It's critical that you realize that there are two types of time travel, and they are radically different. Time travel to the future? Definitely possible. We know how to do it because Einstein showed us the way over a hundred years ago. It’s surprising how few people actually really know about this in their bones. He showed that if you go out into space and travel near the speed of light, and you turn around, and you come back, your clock will be ticking off time more slowly. So, when you step off it's going to be the future on planet Earth. You will have time traveled into the future." http://www.businessinsider.com/how-t...mholes-2017-11

Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian Greene: "Now, listen carefully. The faster you move, the heavier you get. Light travels at the same speed no matter how you look at it. No matter how I move relative to you light travels at the same speed. No matter who is doing the measurement and no matter what direction you are moving the speed of light is the same. The speed of light is the same no matter what direction or how fast... As you travel faster time slows down. Everything slows down. Everything slows down. Time slows down when you move. Time passes at a different rate. Clocks run slow. It's a monumental shift in how we see the world. It's a beautiful piece of science. It's a beautifully elegant theory. It's a beautiful piece of science. It's a beautiful piece..." https://www.youtube.com/watch?v=BuxFXHircaI

https://pbs.twimg.com/media/DcMHjnHWkAEXB8f.jpg

Pentcho Valev
 




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