# A possible proof that negative ageing doesn't occur in special relativity?

Discussion in 'Alternative Theories' started by Mike_Fontenot, Jun 13, 2021.

1. ### Mike_FontenotRegistered Senior Member

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According to the CMIF (Co-Moving-Inertial Frames) simultaneity method, an observer (he) who accelerates in the direction away from a distant person (she) will conclude that she rapidly gets YOUNGER during his acceleration. But I think I may have found a counterexample that shows that doesn't happen.

It is well-known that two stationary clocks at different positions in a gravitational field will run at different rates. The clock that is closer to the source of the gravitational field will run slower than the clock that is farther from the source of the field.

Because of the equivalence principle, it is also true that if two clocks that are separated by a fixed distance "d" ly are both accelerated with a constant equal acceleration of "A" ly/y/y, the trailing clock runs slower than the leading clock, by the factor exp(Ad).

So consider the following scenario:

At some instant, the perpetually-inertial "home twin" (she) is 20 years old, and is holding a display that always shows her current age. Facing her is the "helper friend" (the "HF") of an observer (he) who is "d" ly away to her right. Both the HF and he are also 20 years old, and are stationary wrt her at that instant. Like her, he and the HF are each holding a display that always shows their current ages.

Now, suppose that he and his helper then both start accelerating at a constant "A" ly/y/y toward the right. He knows that his helper friend (the HF) is then ageing at a constant rate that is slower than his own rate of ageing, by the factor exp(Ad).

An instant later, his display shows the time 20 + epsilon_1, where epsilon_1 is a very small positive number. He knows that HF's display shows the time 20 + epsilon_2, where epsilon_2 = epsilon_1 / exp(Ad).
She can still see HF's display (because HF has only moved an infinitesimal distance away from her, to her right). She will see that HF's display reads 20 + epsilon_1 / exp(Ad). And likewise, HF can still see her display. What does HF see on her display? Does HF see that she is now slightly younger than 20? No! It would clearly be absurd for someone essentially co-located with her to see her get younger. HF would see her display reporting that she was some very small amount epsilon_3 OLDER that she was at the instant before the acceleration. HF then sends a message to him, telling him that she was 20 + epsilon_3 right then. When he receives that message, he then knows that her current age, when he was 20 + epsilon_1, was 20 + epsilon_3. So he KNOWS that she didn't get younger when he accelerated away from her. That contradicts what CMIF simultaneity says.

3. ### DaveC426913Valued Senior Member

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I challenge this. I have never heard anyone, or any theory, that claims a relativistically-moving target gets younger, under any circumstances.

Before moving past this first claim, defend it with references.

Actually, since your post is attempting to refute something that's never been claimed in the first place, you reach the right conclusions - but for the wrong reasons.

Your post is a solution without a problem, so really it's a wash.

Last edited: Jun 13, 2021

5. ### BeaconatorValued Senior Member

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Ben German button used a time machine to make himself younger as he aged

7. ### SsssssssRegistered Senior Member

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It's "true" if you string together momentarily comoving inertial frames (see p2 in https://arxiv.org/abs/gr-qc/0104077 for example) but that's just evidence that doing that is a bad idea.

Can't work out what OP is on about because he states measurements and results from different frames and coordinate systems without bothering to specify which one he's using at any time. I expect if he untangles that all his problems will go away.

Last edited: Jun 13, 2021
8. ### Mike_FontenotRegistered Senior Member

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The famous physicist Brian Greene disagrees with you:

https://www.pbs.org/wgbh/nova/video/the-fabric-of-the-cosmos-the-illusion-of-time/

9. ### DaveC426913Valued Senior Member

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I've read the book, more than once. I've read all his books.

That video is unavailable to me, so I'll just have to assume you're interpreting it wrong.

Regardless, there's no need for you to disprove something that's never been claimed. Simply using relativity correctly will achieve that.

Last edited: Jun 13, 2021
10. ### Mike_FontenotRegistered Senior Member

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Since my argument makes use of very small (unspecified) quantities,
it could be argued that time delays due to the speed of light might also need
to be taken into account when describing what the HF sees on her display.
But I think any such concerns can be addressed by pointing out that the
separation "d" between him and her can be made arbitrarily large, and CMIF
simultaneity says that the amount of negative ageing that occurs is proportional
to their separation. Since the errors involved due to the finite speed of light
between her and the HF are independent of the distance "d", those errors
become negligible for sufficiently large "d".

11. ### DaveC426913Valued Senior Member

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There is no such thing as negative aging. You have made that up.

12. ### DaveC426913Valued Senior Member

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If anyone actually wishes to follow this, here is the same thing posted a few weeks ago on another forum (I guess Mike considers SciFo to be sloppy seconds to Google Forums). It is a lot farther along in dismantling Mike's naive ideas about relativity. No need to reinvent the wheel here.

13. ### Mike_FontenotRegistered Senior Member

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360
exchemist likes this.
14. ### DaveC426913Valued Senior Member

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Last edited: Jun 14, 2021
15. ### Mike_FontenotRegistered Senior Member

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I don't know why you can't view that link. It works fine for me. If you still have your copy of Greene's "The Fabric of the Cosmos", he does essentially the same scenario on page 134, starting at the last paragraph.

16. ### DaveC426913Valued Senior Member

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OK, so what you're saying is "My interpretation of Brian Greene's interpretation of relativity in his book tFofC is at best misleading and at worst wrong".

So what? No one else in the scientific community claims that relativity can result in negative aging, so you've beaten down a straw man you built yourself.

Could've saved yourself a lot of time and heartbreak by doing absolutely nothing, and you'd still have arrived in the same place as you are now.

17. ### Mike_FontenotRegistered Senior Member

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Did you actually read the passage starting with the last paragraph of page 134 of his book? In his example, he says that the alien ("Chewie") and you are initially mutually stationary (and separated by 10 billion lightyears), and so Chewie says that the time at your location is currently right now (3:17pm in my time zone in Colorado, on June 14, 2021). Then, Chewie stands up and goes for a walk, in a direction directly away from you. He is walking about 10 miles per hour. As soon as he starts doing that, he then says that the current time on earth is about 150 years before June 14, 2021 ... i.e., he says the date on earth is about 1870, not 2021. I.e., he says you just got younger by 150 years ... you haven't even been born yet, and neither have about 6 or 7 generations of your ancestors, according to Chewie. THAT is negative ageing.

Last edited: Jun 14, 2021
18. ### DaveC426913Valued Senior Member

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Stop reading pop-sci books and taking their oversimplified examples as real science.

What you're doing is tantamount to examining a fax of a treasure map and wondering why the terrain is made of tiny squares.

This does not belong in the hard science forum - it is a personal theory. It belongs in the Alt Theories forum. I have reported it to have it moved.

19. ### Mike_FontenotRegistered Senior Member

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In your post #6, you said

"I've read the book, more than once. I've read all his books."

Now you say it's a "pop-sci" book that shouldn't be believed?

The bottom line is that Brian Greene clearly DOES believe that an accelerating observer who accelerates in the direction away from a distant person will conclude that that distant person gets younger during the acceleration.

I don't know how many other physicists believe that. Many other prominent physicists were part of Greene's NOVA show (like Sean Carroll, for example), and I don't think they would have done that if they thought he was wrong.

I think I'm in pretty good company.

20. ### DaveC426913Valued Senior Member

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It should not be taken as literally as you are taking it. His example is not meant to be rigorous.

No. More like one might naively conclude that - if one does not do his calculations correctly. That's often how such examples are presented in books - and then they may go on to show how this is not actually the case.

Zero.

Well, technically, minus one, since Greene doesn't either.

He's not "wrong" - in the same sense that the faxed treasure map is not wrong. It's simplified, and is presented for the layperson. It is not mean to be taken as literal truth.

Surely you have not based all your work on a couple of paragraphs in one book of one pop sci author - ignoring that fact that no other scientists hold the same view? Surely.

Last edited: Jun 14, 2021
21. ### phytiRegistered Senior Member

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Mike;

I've had exchanges with Mike on other forums over the years. Whenever he gets knocked down, he gets back up, reinvents himself and his theory and tries to sell it.
I would like to nominate him for the Perseverance Award.
His idea is already in the 'alternate theories'.

Mike has bad sources, and relies on authority figures.

Truth is in the statement, not who proclaims it.

In the video, Brian Greene is pushing the 'block universe', which is a later form of Relativity, where every event past, present, and future continuously exists. Many physicists accept this idea.
An immediate problem arises. Where was the event 'LIGO detects gravitational waves'
before 2016 when it actually occurred?
Greene's aging example can be visualized in a graphic.

On the left, B moves away from A at t'2 with an instantaneous change of direction and a corresponding change of his x' axis or axis of simultaneity. It would point to t1 on the At axis, earlier than t2. T1 is an historical clock event, i.e. it has already occurred, and the blue light signal from B is returning to B, thus he hasn't assigned a corresponding B-time. The clock event can't occur twice since time is cumulative!

On the right, B moves away with the discontinuous paths joined with a realistic transition joining the two. The aos changes sequentially, but always in the positive time sense.

Brian Greene and others use metaphors like 'moving in time' for a more dramatic effect. It's a better form of self promotion.

22. ### Write4UValued Senior Member

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18,612
But that would be relatively speaking. If I age faster that you, you will relatively age slower and become younger the more time passes. But neither of us would get younger than what we were to begin with.

23. ### Neddy BateValued Senior Member

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Even in the CMIF simultaneity method, no one ever visually sees anyone getting younger, ever. So you have proven absolutely nothing.