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No. For one thing, they calculate the timing differently regardless of the travel time of light (due to relativity of simultaneity). For another thing, (only) the twin who turns around sees the change in relative velocity immediately.

The situation is asymmetric, as explained in many ways. It is measured differently, seen differently, felt differently, timed differently. The symmetrical slowing of clocks and the resulting "paradox" is only a partial application of SR. You know the situation is asymmetrical, but you think that applying a part of SR keeps it symmetrical. However, a full application of SR (considering time dilation, length contraction, and relativity of simultaneity) resolves the paradox and shows you where the differences are. You are fighting every explanation that involves SR, yet you keep demanding an explanation of SR. I don't think you'll get much further without understanding the theory a bit more. Keep in mind that you're so sure that the other twin's clock ticks slower, but why? Just because it is predicted by SR? Do you see the physical mechanism for it? If so, what is it? And if not, then why do you require a physical mechanism for the other predictions of SR while rejecting the other theoretical predictions and explanations? Eg. the traveling twin does not remain in an inertial frame, so the "slowing of other clocks" doesn't apply without relativity of simultaneity.

If you work through some examples with numbers, it might give you a concrete understanding of the important concepts and make it impossible to brush them aside.

The explanation has nothing to do with relativity of simultaneity. To get a correct grasp of what is going on, one needs to apply the equations of accelerated motion in SR. The difference between the elapsed times is due to the presence of acceleration in the case of the "traveling twin". See the detailed explanation here.

The traveling twin measures an elapsed time of $\Delta \tau = 2 T_c / \sqrt{ 1 + (a \ T_a/c)^2 } + 4 c / a \ \text{arsinh}( a \ T_a/c )$.

The "inertial twin", measures an elapsed time of $\Delta t = 2 T_c + 4 T_a\,$.

A little bit of calculus shows that :

1. $\Delta t > \Delta \tau\,$ for $a \ne 0$

2. $\Delta t = \Delta \tau\,$ for $a = 0$

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It breaks the symmetry. It allows you to know whose clock was running slow; while the symmetry exists there is no answer to that.

So you're implying that prior to that turn around it is symmetrical, both observers would observe the same dilation of each other and we wouldn't know which one had "actually" accelerated to get to near the speed of light until one bothered to turn around and come back?

The explanation has nothing to do with relativity of simultaneity. To get a correct grasp of what is going on, one needs to apply the equations of accelerated motion in SR. The difference between the elapsed times is due to the presence of acceleration in the case of the "traveling twin". See the detailed explanation here.

The traveling twin measures an elapsed time of $\Delta \tau = 2 T_c / \sqrt{ 1 + (a \ T_a/c)^2 } + 4 c / a \ \text{arsinh}( a \ T_a/c )$.

The "inertial twin", measures an elapsed time of $\Delta t = 2 T_c + 4 T_a\,$.

A little bit of calculus shows that :

1. $\Delta t > \Delta \tau\,$ for $a \ne 0$

2. $\Delta t = \Delta \tau\,$ for $a = 0$

delta-tau almost looks like something to do with the arclength equation, and I remember running into that when I was playing around with space curvature on my own. That arclength wouldn't happen to correspond to the direct result of the addition time it would take to travel the extra distance that a near-light traveler would see would it? Because that would make a lot of sense, but I couldn't make as much sense of the situation because I was in purely standard Cartesian coordinates and I didn't know exactly what I was doing, so I have no idea what I actually found, but it looked almost exactly like a relativistic velocity equation.

Edited by SamBridge

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So you're implying that prior to that turn around it is symmetrical, both observers would observe the same dilation of each other and we wouldn't know which one had "actually" accelerated to get to near the speed of light until one bothered to turn around and come back?

Essentially yes, you can set it up that way. In your set up it is that way. On the other hand, if for example you had specified a long period of acceleration for one of the twins, then that involves a different velocity profile for the twins. That will make the situation more complicated but it won't change who ages more in the end.

Here's how to prove that the one who accelerates away doesn't matter: First, take Earth out of the picture, and call the twins A and B. Suppose one will turn around half-way through the experiment, and the other will remain inertial (other than any initial separation acceleration). Calculate the results you get if A accelerates away but B turns around, or if B accelerates away and B turns around, or if they both accelerate away symmetrically and B turns around. Once they have that initial departing velocity, twin A now remains inertial for the rest of the experiment and will age more over that time, regardless of who accelerates in the beginning. If you assume a negligible acceleration time, then "who accelerates away" makes a negligible difference, and you can see that in the Lorentz transformation.

You can ignore this part or really any answer until you understand the basics, but if the twins start symmetrically with a relative velocity, and one turns around after a proper time of tau, then the situation is symmetrical up to a proper time of tau for either of the twins. For example with gamma=2, and twin B turning around at tau=1 unit of time, up till then B calculates A aging 0.5. Symmetrically, up till A ages a proper time of 1, it has that B ages 0.5. But for A the situation isn't symmetrical "up until the time of the turn around", because for A that happens at local time 2, when B has aged 1. Twin A experiences aging from 1 to 2 without a turnaround, and B never experiences that in this setup, so it is not symmetrical beyond local time of 1. As an example, if the setup is "the twins depart symmetrically with relative velocity v=0.866c. At local time of 1, exactly one of the twins will receive a signal to turn around. Who will turn around is unknown at the start." Up until time 1, there is no distinguishing features between the twins; the situation must be symmetrical. However if a twin passes a time of 1 and hasn't got the signal, it knows that it isn't the twin that turns around, EVEN THOUGH the other twin has only aged 0.5 units of time and it is only halfway to the time that it will receive the turn-around signal. There is nothing odd about any of this unless you reject relativity of simultaneity.

Also this is not "flip-flopping", it is "relativity". The various different points of view are mutually consistent.

Edited by md65536

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So you're implying that prior to that turn around it is symmetrical, both observers would observe the same dilation of each other and we wouldn't know which one had "actually" accelerated to get to near the speed of light until one bothered to turn around and come back?

The initial acceleration is ignored and assumed to be infinitely short. Since it happens at the outset of the problem, there is no accumulated time dilation. Thus it is irrelevant. With the phrasing of the problem, which ignores everything prior top the experiment, it wouldn't matter which twin underwent this acceleration.

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You can ignore this part or really any answer until you understand the basics, but if the twins start symmetrically with a relative velocity, and one turns around after a proper time of tau, then the situation is symmetrical up to a proper time of tau for either of the twins. For example with gamma=2, and twin B turning around at tau=1 unit of time, up till then B calculates A aging 0.5. Symmetrically, up till A ages a proper time of 1, it has that B ages 0.5. But for A the situation isn't symmetrical "up until the time of the turn around", because for A that happens at local time 2, when B has aged 1. Twin A experiences aging from 1 to 2 without a turnaround, and B never experiences that in this setup, so it is not symmetrical beyond local time of 1. As an example, if the setup is "the twins depart symmetrically with relative velocity v=0.866c. At local time of 1, exactly one of the twins will receive a signal to turn around. Who will turn around is unknown at the start." Up until time 1, there is no distinguishing features between the twins; the situation must be symmetrical. However if a twin passes a time of 1 and hasn't got the signal, it knows that it isn't the twin that turns around, EVEN THOUGH the other twin has only aged 0.5 units of time and it is only halfway to the time that it will receive the turn-around signal. There is nothing odd about any of this unless you reject relativity of simultaneity.

So how can the first part of the experiment be symmetric if A doesn't actually observe the same effects as B and only one experiences a greater specific time dilation? I thought both you and swan said that it actually was symmetric in the first half, then you said But for A the situation isn't symmetrical 'up until the time of the turn around'" which implies it's symmetric after the turn-around and "Twin A experiences aging from 1 to 2 without a turnaround" si it's not symmetric prior to the turn around? What do I do with what you said there? It's like you threw away what you said in the first paragraph.

But, assuming the part of what both said is correct which is that it's symmetric in the first half, and we have two twins that are constantly trying to observe each other, you're saying the asymmetric comes at first from the fact that traveling twin B has already turned around hours ago by the time Earth twin A has observed the photons that suggest the twin has turned around, so B says the turn around happened at a later time than A, and by that time, A is already well on it's way back to Earth, so A should arrive there somewhat before B says it should have, making A younger?

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so B says the turn around happened at a later time than A, and by that time, A is already well on it's way back to Earth, so A should arrive there somewhat before B says it should have, making A younger?

No. Try again using some actual maths that correspond with SR. If you get stuck, post what you've got so far. Otherwise I'll just be repeating.

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So how can the first part of the experiment be symmetric if A doesn't actually observe the same effects as B and only one experiences a greater specific time dilation? I thought both you and swan said that it actually was symmetric in the first half, then you said But for A the situation isn't symmetrical 'up until the time of the turn around'"

"if the twins start symmetrically with a relative velocity, and one turns around after a proper time of tau, then the situation is symmetrical up to a proper time of tau for either of the twins." is the opposite of what you claim above. You've turned an is into an isn't.

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"if the twins start symmetrically with a relative velocity, and one turns around after a proper time of tau, then the situation is symmetrical up to a proper time of tau for either of the twins." is the opposite of what you claim above. You've turned an is into an isn't.

Well, no, I think what SamBridge said is consistent with what I said.

Say twin A ages 4 years over the experiment and B ages 2, with the usual setup. Twin A's clock measures a proper time of 4 years between separation and reuniting, and B's clock a proper time of 2 years. The situation is symmetrical up to 1 year by either clock. But the turnaround doesn't happen until year 2 on A's clock, as observed by A. So it is not fully symmetrical right up until the turnaround.

Another way to put it is that each twin observes the turnaround happening halfway through the experiment, but the duration of half the experiment isn't symmetrical.

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Another way to put it is that each twin observes the turnaround happening halfway through the experiment, but the duration of half the experiment isn't symmetrical.

Ok, so, if in the first half of the experiment, both frames of reference can agree on how much time has passed up to the turn-around event, but not after, so can we agree that the duration of the trip prior to any turn-around is symmetric? Because otherwise, it's still the same problem as before where I don't see a physical phenomena to account for the physical age difference of why A and B don't observe the exact same dilation effects of each other in just the first part of the experiement. Like I said before if twin B moves away from A at 80% the speed of light, twin B observes twin A moving away at 80% the speed of light instead. Where is the asymmetry in just, only and purely in that scenario with no turnaround even? Let's just make sure that's established. Twin A says twin B is moving 80% c away, so twin B says twin A is moving 80% c away, no one has turned around yet. Is only that scenario symmetric? Or will they both observe the same dilation effects of each other or not?

Edited by SamBridge

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Ok, so, if in the first half of the experiment, both frames of reference can agree on how much time has passed up to the turn-around event,

No.

Put it in numbers. Write down the times of these events in your example, so that calculations can actually be done to determine the answers. Is there any example with actual numbers where what you wrote makes sense?

A caveat, everyone will agree on how much time has passed for B at the time of B's turnaround. Different observers will not agree on the time at A that is simultaneous with B's turnaround.

Like I said before if twin B moves away from A at 80% the speed of light, twin B observes twin A moving away at 80% the speed of light instead. Where is the asymmetry in just, only and purely in that scenario with no turnaround even? Let's just make sure that's established. Twin A says twin B is moving 80% c away, so twin B says twin A is moving 80% c away, no one has turned around yet. Is only that scenario symmetric? Or will they both observe the same dilation effects of each other or not?

Yes, with no turnaround the situation is symmetric. They'll both observe the other symmetrically. The relativistic effects will be symmetrical.

Careful with the word "yet" because it is different for different observers. If you add an event at B's location, it has a definite time on B's clock, but does not have a definite time on A's clock.

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No.......................................

Yes........................................

Dude, what are you even saying anymore?

ONLY the first half of the experiment where no initial acceleration is considered and we're not talking about the turn-around, only twin A and twin B, no one else and no initial acceleration is considered, just only that, don't comment on anything else yet. Is THAT situation situation of only Twin A and Twin B observing each other traveling nearing the speed of light symmetric? An as a separate question to make it very clear to and to answer in a different paragraph that does not try to relate to the first paragraph, is there any physical reason in that scenario why they would not observe the same dilation effects of each other?

Edited by SamBridge

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Dude, what are you even saying anymore?

'No' was to your first question. 'Yes' was to your other question.

ONLY the first half of the experiment where no initial acceleration is considered and we're not talking about the turn-around, only twin A and twin B, no one else and no initial acceleration is considered, just only that, don't comment on anything else yet. Is THAT situation situation of only Twin A and Twin B observing each other traveling nearing the speed of light symmetric? An as a separate question to make it very clear to and to answer in a different paragraph that does not try to relate to the first paragraph, is there any physical reason in that scenario why they would not observe the same dilation effects of each other?

To repeat, the twins do NOT agree on how long half of the experiment is. You can't describe "half the experiment" as a universal duration and make sense of that from everyone's perspective.

To repeat, yes THAT situation is symmetric.

I don't know of any way to understand relativity without learning about relativity. If you want shortcuts, to somehow get understandable answers to situations you can't make sense of, then ignore my posts. I don't think they're helping. I think it would be more productive to research the basics of special relativity first.

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To repeat, the twins do NOT agree on how long half of the experiment is. You can't describe "half the experiment" as a universal duration and make sense of that from everyone's perspective.

To repeat, yes THAT situation is symmetric.

I'm not talking about how long half the experiment is, I'm asking if they observe the same time dilation of each other, not if they observe the same length contraction to the star. They definitely wouldn't have a reason to observe the same length contraction from a point to the star because the star is stationary from only one twin's frame. The problem I'm asking about doesn't come from them disagreeing on how far away the star is, it comes from them disagreeing about what they see of each other. The basis of the paradox, they should both see each other dilated the same but they can't both be younger at the same time. It's what they constantly see of each other in the first half that doesn't uphold the paradox that I don't see, and I think that has more to do with the relativistic Doppler effect.

To repeat, yes THAT situation is symmetric.

Ok, that's what I wanted to confirm. Maybe they don't agree on how long it takes to get to the star, but now I want to ask, can I extrapolate that they still observe the same time dilation of each other for that first half if they had good enough telescopes to constantly observe each other? Then, I think the explanation to that one will help, because that's really a main component that I've been asking about the whole time.

Now maybe if all the previous stuff is good, we can move on to one other scenario which will hopefully make it clear. Let's say out of sheer coincidence, every atom of the traveling twin spontaneously teleported back to Earth as per their indefinite mathematical probabilistic boundaries hypothetically mathematically allowing them to do so even though that would probably never happen. Who will have aged less?

And then, let's say they repeated the experiment, but the traveling twin only teleported after the turn around, no room for Doppler shift and illusions of light waves piling up or being in further intervals apart. If this happened would they observe light from them and say they are in two places at once? Sure, the spacial part of relativity isn't going to like being cut out, but I think isolating only what happens to the time is the most important because that's what the paradox is ultimately addressing and it might also show why the relativistic Doppler effect is important and more than just an illusion, why the times are different despite the symmetry in the first half of the experiment, how the clocks match up during the entirety of the experiment.

Let's even ask this just to see the effects of the teleportation. If one twin went near a super-massive black hole, then instantly teleported back before any photons got to Earth, would they still be younger? Would being in contracted space have physically caused the clock to actually tick slower? If the answer is yes, we can take it to the next level with when one twin is traveling since we could fall back on the equivalence principal anyway.

Edited by SamBridge

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I'm not talking about how long half the experiment is, I'm asking if they observe the same time dilation of each other, not if they observe the same length contraction to the star. They definitely wouldn't have a reason to observe the same length contraction from a point to the star because the star is stationary from only one twin's frame. The problem I'm asking about doesn't come from them disagreeing on how far away the star is, it comes from them disagreeing about what they see of each other. The basis of the paradox, they should both see each other dilated the same but they can't both be younger at the same time.

And here is what the crux of the problem is. You think the phrase "they can't both be younger at the same time" actually has meaning in this situation. It doesn't. There is no Absolute, Universal meaning to "at the same time". "At the same time" is frame dependent. "At the same time" in the Traveler's frame is different than "At the same time" in the Earth frame. There is no way to apply this term to both frames universally. In the traveler frame the Earth twin really is younger than him at the moment before turn around, and in the Earth twin frame, the traveling twin is really the younger. I know that this seems contrary to the way we seem to experience time, but it is the way that time works in our universe.

Ok, that's what I wanted to confirm. Maybe they don't agree on how long it takes to get to the star, but now I want to ask, can I extrapolate that they still observe the same time dilation of each other for that first half if they had good enough telescopes to constantly observe each other? Then, I think the explanation to that one will help, because that's really a main component that I've been asking about the whole time.

Each will see the other twin's clock as ticking slower than their own by the same rate as long at they see the other receding.

Now maybe if all the previous stuff is good, we can move on to one other scenario which will hopefully make it clear. Let's say out of sheer coincidence, every atom of the traveling twin spontaneously teleported back to Earth as per their indefinite mathematical probabilistic boundaries hypothetically mathematically allowing them to do so even though that would probably never happen. Who will have aged less?

And then, let's say they repeated the experiment, but the traveling twin only teleported after the turn around, no room for Doppler shift and illusions of light waves piling up or being in further intervals apart. If this happened would they observe light from them and say they are in two places at once? Sure, the spacial part of relativity isn't going to like being cut out, but I think isolating only what happens to the time is the most important because that's what the paradox is ultimately addressing and it might also show why the relativistic Doppler effect is important and more than just an illusion, why the times are different despite the symmetry in the first half of the experiment, how the clocks match up during the entirety of the experiment.

Let's even ask this just to see the effects of the teleportation. If one twin went near a super-massive black hole, then instantly teleported back before any photons got to Earth, would they still be younger? Would being in contracted space have physically caused the clock to actually tick slower? If the answer is yes, we can take it to the next level with when one twin is traveling since we could fall back on the equivalence principal anyway.

The instant you try to throw instantaneous travel or transfer of information into the mix, you invalidate SR, so there is no SR based answer to this question.

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And here is what the crux of the problem is. You think the phrase "they can't both be younger at the same time" actually has meaning in this situation. It doesn't. There is no Absolute, Universal meaning to "at the same time". "At the same time" is frame dependent. "At the same time" in the Traveler's frame is different than "At the same time" in the Earth frame. There is no way to apply this term to both frames universally. In the traveler frame the Earth twin really is younger than him at the moment before turn around, and in the Earth twin frame, the traveling twin is really the younger. I know that this seems contrary to the way we seem to experience time, but it is the way that time works in our universe.Each will see the other twin's clock as ticking slower than their own by the same rate as long at they see the other receding.The instant you try to throw instantaneous travel or transfer of information into the mix, you invalidate SR, so there is no SR based answer to this question.

I use to think it could work like that too, then I saw this topic and got involved. Regardless of simultaneity, as you said which was my exact point I was trying to confirm or deny, "Each will see the other twin's clock as ticking slower than their own by the same rate as long at they see the other receding." I think I'm starting to see that the problem with THAT is that you'd need some other frame of reference, otherwise how could you know that they both tick slower by the same rate? Earth certainly doesn't think its own clock ticks slower.

The instant you try to throw instantaneous travel or transfer of information into the mix, you invalidate SR, so there is no SR based answer to this question.

As I said, black hole. If the effects of time dilation are physically real and not just some illusion that involves the Doppler effect, then it doesn't matter how long photons take to reach anything, the curvature of space will still slow a clock down and Earth will say the black hole traveler is younger when the traveler teleports back. You didn't really think you were getting out of it that easily did you? Why would I bother to bring it up if anyone would be satisfied with a lack of even a single attempt at an answer? Would you observe someone being in two places at once? Probably, they'd teleport but the light from their previous position would take a finite time to reach Earth, but, I don't care, because all I'm investigating in that scenario is the nature of just the time dilation, not in combination with relativistic velocity acceleration with the traveling twins yet, just the physical ticking of the clocks.
Edited by SamBridge

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I use to think it could work like that too, then I saw this topic and got involved. Regardless of simultaneity, as you said which was my exact point I was trying to confirm or deny, "Each will see the other twin's clock as ticking slower than their own by the same rate as long at they see the other receding." I think I'm starting to see that the problem with THAT is that you'd need some other frame of reference, otherwise how could you know that they both tick slower by the same rate? Earth certainly doesn't think its own clock ticks slower.

Each observer measures the other clock's rate as compared to his own clock. So when the traveler says the Earth clock ticks slower, he means as compared to his own clock. And when the Earth clock says the Traveler's clock ticks slower it is as compared to his own clock. The point is that any comparison of clock rates have to be made from some reference frame, and how those clock rate compare depend on the reference frame. There is reference frame in which both the Earth clock and traveler clock tick slower than the local clock, but tick at the same rate as each other.

These comparisons of clock rates as measured from frames reference are the only comparisons of time rates that can be made. There is no "outside reality" from which you can view this which tells you which clock "really" is running slower than the other.

Even with the twin paradox, after the twins have reunited, and everyone agrees that one twin has aged more than the other, everyone does not agree as to why this is the case. Some frames will say it is because one twin aged slower than the other for the entire trip, while other frames will say that which twin aged slower than the other changed throughout the trip. And both are equally true. There is no one "truth" to what happened.

Such is the nature of space-time. You keep trying to invoke some kind of universal background by which time is "really" measured, and no such thing exists.

As to the other comments, just saying "black Hole" doesn't change anything. So you are adding in curved space-time and thus GR, but GR encompasses SR, as SR is just a subset of it. So instantaneous transportation is still incompatible. You can't get a valid, internally consistent model by mixing SR and instantaneous travel.

Edited by Janus

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/quote]

Each observer measures the other clock's rate as compared to his own clock. So when the traveler says the Earth clock ticks slower, he means as compared to his own clock. And when the Earth clock says the Traveler's clock ticks slower it is as compared to his own clock. The point is that any comparison of clock rates have to be made from some reference frame, and how those clock rate compare depend on the reference frame. There is reference frame in which both the Earth clock and traveler clock tick slower than the local clock, but tick at the same rate as each other.

These comparisons of clock rates as measured from frames reference are the only comparisons of time rates that can be made. There is no "outside reality" from which you can view this which tells you which clock "really" is running slower than the other.

Even with the twin paradox, after the twins have reunited, and everyone agrees that one twin has aged more than the other, everyone does not agree as to why this is the case. Some frames will say it is because one twin aged slower than the other for the entire trip, while other frames will say that which twin aged slower than the other changed throughout the trip. And both are equally true. There is no one "truth" to what happened.

Such is the nature of space-time. You keep trying to invoke some kind of universal background by which time is "really" measured, and no such thing exists.

Even though I don't completely understand it, but It seems like you keep disregarding what everyone else went to great lengths to explain which is that only one twin actually accelerated and every frame inertial frame would know it, the principal of everyone of a certain frame not being able to agree on something only applies to inertial frames, it works different with accelerated frames. If you look at gravitational fields and something moving towards a black hole, every frame in the universe can agree that something is moving from a lower gravitational field strength to a higher one, even if they can't agree on when because of dilation and distance, and that's because a gravitational field creates an accelerated frame of reference from the curvature of space.

What's been suggested is that both twins can ultimately agree on which one underwent acceleration, and thus, which twin is younger. And, if time actually did travel slower at the same rate for both frames, that would imply they are in the same frame of reference and thus there should be no reason to see a difference in what they measured of each other

If you take away the acceleration and teleport back, I'm not sure what happens when they re-unite. One twin was traveling near the speed of light, so from Earth's frame and the traveling twin's frame, both twins will know that only one twin traveled a shorter measured distance to the star due to length contraction and dilation, that's all fine. What isn't clear is the teleportation thing or a way to analyze what is physically happening, which twin actually experienced less or more time if one happened to teleported back to Earth, if the effects of light travel remained in place but the rate they received information about each other was instantaneous.

In fact why don't you answer it. If the traveling twin teleported back to Earth, how would both clocks be slower than each other? If someone went near a black hole and then teleported back to Earth, the black hole traveler's clock should still be slower because only that clock experienced a comparatively higher curvature of space and did not count time in the same metric length (yup) as a clock on Earth, so I know reality doesn't fall apart with teleportation, especially considering wormholes were seriously considered by the scientific community to be physically possible, I know there's potential answers.

Edited by SamBridge

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Your basically asking what would happen if the laws of physics did not apply. There is no teleportation, there is no time travel, there is no traveling faster than light, and to ask what would happen if there were is a question with no answer other than speculation.

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Your basically asking what would happen if the laws of physics did not apply. There is no teleportation, there is no time travel, there is no traveling faster than light, and to ask what would happen if there were is a question with no answer other than speculation.

There use to not be relativity, newtonian physics, string theory, quantum physics, thermodynamics, ect. It's completely ridiculous to suggest people do not have the capability to imagine something different or explore other possibilities, there is absolutely zero reason to be afraid of exploring these things and simply saying "what if..." If people didn't say "what if..." science would not exist as we know it today. No one would have said "what if light had a constant speed" "what if time wasn't universal" "what if matter could act like a wave" "what if energy wasn't conserved" "what if c wasn't the universal speed limit" "what if you could bend space," what you're saying is just utterly ridiculous. It's completely possible to speculate on such things, make logical deductions and use mathematics, I already made a hypothesis with black holes and teleportation. In fact, I can do it with known physics itself. What if there was no speed limit like light? Mathematically as c approaches infinity, it takes noticeable longer when gaining velocity before you start seeing the effects of time dilation, so I can speculate that as the speed of light approached infinity, the effects of time dilation and length contraction when accelerating approach 0. It doesn't even have to be a physical phenomena that actually happens, it just has to explore something to see how certain variables work, how important they are, how things might be different, why we see things the way we do by observing contrasts. There's no way you're going to get away with saying "we can't speculate on anything," not with me around. What if gravity was 2 times stronger than it is now? You'd say its impossible to know anything because that's not happening in reality, not to suggest that such a phenomana is impossible anyway since higgs fields have different theoretical excitation states, but any real mathematician in the world would just plug in the numbers or just use simple intuition and see that it takes less mass for stars to super-nova, Earth would have a stronger gravitational field, it would take more energy to get to a greater height, ect. We have multiple models for the universe and how to model phenomena, they can't all be correct, but that doesn't stop anyone from exploring anything and playing around with physics and asking more questions and finding more answers.

Edited by SamBridge

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To ask how physics would work without the laws of physics, is to enter the realm of science-fiction.

What if gravity was 2 times stronger than it is now?

That's dealing with physics within the framework of physics. It's just an environmental factor.

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There's no way you're going to get away with saying "we can't speculate on anything," not with me around.

There's always the Speculations forum, which would be more appropriate.

I think your ideas and questions would fit in well there. If you're going to reject relativity theory, you'll probably never get satisfactory answers in the Relativity forum.

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To ask how physics would work without the laws of physics, is to enter the realm of science-fiction.

No one's asking how all of physics would work without all of physics, someone is asking how specific pieces of physics would work if only a specific piece was changed like in every single respectively newer theory ever conceived in the history of man kind.

That's dealing with physics within the framework of physics. It's just an environmental factor.

Then think of the speed of information as an environmental factor.

I think your ideas and questions would fit in well there. If you're going to reject relativity theory, you'll probably never get satisfactory answers in the Relativity forum.

Except saying relativity is being rejected is just a strawman to avoid answering a question. I specifically said the purpose of the question was to observe the importance of other variables by observing contrasts the effects laws working differently. IF someone was transported, we know even without speculation, both clocks could not be near each other and simultaneously both be younger than each other. We don't even need mathematics, we just use what we already know to determine that even though we say that such a circumstance wouldn't happen.

Edited by SamBridge

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I specifically said the purpose of the question was to observe the importance of other variables by observing contrasts the effects laws working differently.

But the laws don't work differently. So any speculation is idle.

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But the laws don't work differently. So any speculation is idle.

I guess Einstein should have said goodbye to special relativity then and the several different models of particle physics can't all be correct so they should all be disregarded. Nothing can ever be gained by isolating the effects of certain variables or seeing how things might work differently so we should give up everything. What a great leap forward.

OR, you can be rational and accept there are things to gain by looking at different scenarios like "we know it can/can't be this outcome because if it did work in this way, this conflicting thing would happen."

Like for instance, we know both frames of reference of the twins are respectively correct because if they weren't and one could instantly teleport back, we'd see...

Or, "we would know only one aged less because of one teleported back we'd see..."

Or, "even if one did teleport back, we wouldn't see..."

Or maybe, "we could theoretically confirm changes in time and not just some illusion of shifts in the frequency of events if someone teleported back from being near a black hole..."

Let's consider this too: We observe light from galaxies that are millions of years old, but just because the light look time to get to us doesn't mean those galaxies only experienced that much aging. From our current models, the inertial frames of any other distant galaxy must have aged along with the ones around us no matter how long it took the light to reach us because they must have been counting time at the same rate, assuming that we're neglecting objects like black holes and treating galaxies as solid objects that have the same mass as our own galaxy. The only thing we don't know is if something happened in between that changed the frame of reference to being in an accelerated frame. But, assuming galaxies continue along their path, if we spontaneously teleported to one, we find that it did actually age 13 billion years as our galaxy did.

Edited by SamBridge

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No one's asking how all of physics would work without all of physics, someone is asking how specific pieces of physics would work if only a specific piece was changed like in every single respectively newer theory ever conceived in the history of man kind.

The physics you want to cite doesn't exist. Your "what if" question violates known physics, and you can't simply ignore the physics that you violate — physics is massively interconnected, so changing one part has ramifications, and you have to account for the domino effect of your changes. If you can't build a self-consistent model that includes the changed bit, you are out of luck.

What Einstein did with relativity was self-consistent. And, as it turns out, something that also described how nature behaves. But relativity means that you can't exceed c, which means if you did (as with teleportation) then relativity can't tell you what happens.

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