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My particles move with regard to one another, and they only use the light emitted by the other particle to do so. That light tells them to resist to acceleration, to get speed, to get a direction, and to move at constant speed when acceleration has stopped. Isn't that enough to call it an absolute reference?...

Quote from: MikeFontenot on 27/10/2018 15:12:35The apparent paradox in the twin "paradox" scenario arises because it would seem that each twin should conclude that the other twin is ageing more slowly, due to the well-known "time-dilation" result, during the entire trip, except for the single instant at the instantaneous turnaround ... "surely" nothing could happen to peoples' ages during a single instant. But that assumption is wrong: the traveling twin must conclude that the home twin's age instantaneously increases during the instantaneous turnaround.Double the length of his trip and see what happens. When he turns round, his twin ages not 27 years in an instant, but 54 years. How can an identical acceleration cause double the ageing?

The apparent paradox in the twin "paradox" scenario arises because it would seem that each twin should conclude that the other twin is ageing more slowly, due to the well-known "time-dilation" result, during the entire trip, except for the single instant at the instantaneous turnaround ... "surely" nothing could happen to peoples' ages during a single instant. But that assumption is wrong: the traveling twin must conclude that the home twin's age instantaneously increases during the instantaneous turnaround.

Because the effect of the instantaneous velocity change is directly proportional to the separation of the twins.

Quote from: MikeFontenot on 01/11/2018 18:02:13Because the effect of the instantaneous velocity change is directly proportional to the separation of the twins.[...]

A few years ago, a well-respected physicist named Brian Greene (best known as a string theorist) did a TV show for NOVA, and gave an example that gets the same results that I've given in this thread. The link below is a short YouTube clip of his example. Scan to the 6:00 point: https://www.youtube.com/watch?v=VYZQxMowBsw

[...]So, here we have the twin boys, both apx. 7 years old and right together for a moment at the same Spacetime location, but one of them asserts that their twin sister is 6 while the other asserts that she is 12. They can't both be right.

Each observer has a different "view" about what "now" is at a distance, and each observer's perspective is equally valid.

Quote from: MikeFontenot on 02/11/2018 13:35:51Each observer has a different "view" about what "now" is at a distance, and each observer's perspective is equally valid.That's a contradiction. Even if the two twins see the other twin as the one who ages less, once reunited, only one of them will be right, [...]

just like the famous time-dilation produces no inconsistency when it says that both inertial observers moving relative to each other will each say the other is ageing more slowly.

If motion is relative, then there is no way to tell which twin is actually moving with regard to the other, except if we know which one has accelerated.

Pretty easy to find counterexamples for this claim.

Quote from: David Cooper on 28/10/2018 17:08:45[...]So, here we have the twin boys, both apx. 7 years old and right together for a moment at the same Spacetime location, but one of them asserts that their twin sister is 6 while the other asserts that she is 12. They can't both be right.They ARE both right!

Quote from: MikeFontenot on 02/11/2018 13:35:51Quote from: David Cooper on 28/10/2018 17:08:45[...]So, here we have the twin boys, both apx. 7 years old and right together for a moment at the same Spacetime location, but one of them asserts that their twin sister is 6 while the other asserts that she is 12. They can't both be right.They ARE both right!Fine, but it's important to make sure everyone understands that that only "works" in an eternal static block universe version of SR. It "works" there because the 6=12 bit becomes 6y=12y while y=0 (which is possible because actual time is completely absent from that model). However, for any model with real, running time, y has to be greater than zero and you then run into contradictions if you try to claim that both twins are right. By using y=0 you're restricting yourself to an eternal static block universe model, but so long as you understand that you're doing so (and don't care that all causality then becomes a mere illusion of causation), and so long as you don't mix this with any incompatible models where time runs, then that's fine.

I don't understand your comments at all. Time is certainly not absent from my CADO reference frame, or from my CADO equation. I'd like to see the contradictions you refer to above.

Quote from: MikeFontenot on 03/11/2018 22:25:15I don't understand your comments at all. Time is certainly not absent from my CADO reference frame, or from my CADO equation. I'd like to see the contradictions you refer to above.I would hope that you agree that 6=12 is a contradiction. 6y=12y is also a contradiction if y>0. In a model with running time, y>0, and that means that in such a model it is not possible for both the twins to be right about the age of their twin sister. The only way you can get away with 6y=12y is if y=0, but that's a model with no time in it - all it has is a static "time dimension". A "time dimension" is not time, but just a special kind of space dimension in which all objects have infinite length. "Past" and "future" in such a model are mere directions like up and down, or left and right. A model only has real time in it if there is change, but in a static block model there is never any change: the entire future is pre-existing and was never generated out of the past.If you're using a model with real time, you can then run events and see if the girl can be 6 and 12 years old at the same time. I can tell you for free that she can't. You can change the way you run the simulation by slowing clocks in different ways, but you'll find that there's always one age that she has at the point when her twins are arguing about her age. If you go for a model where no clocks run slow, you'll find that the boys get back to the reunion point where they meet her again before she's arrived, so you run into event-meshing failures, but even if you go for a model that erases those failures over Newtonian time, then you find that the girl is actually 7 when her brothers (both 7) are arguing about her age. These models are not compatible with each other and should not be mixed. If you want the girl to be 6 and 12 at the same time, you have to use a static block model where that's possible because it's 6x0 = 12x0 and there is no time in the model. You can take your pick, but please don't mix incompatible models and pretend that the girl can be 6 and 12 at the same time in any model with running time. Mathematics does not allow that.

The above still just sounds like gibberish to me. I think you and I will just have to agree to disagree, to keep from wasting any more time and keystrokes.