Nobody, I searched 5 pages looking for the site, to no avail. Now this time I found it right away. It is completely different than your first one, though.

The gist of your citation seems to be "A lot of [TP] explanations,,have claimed it is necessary to include a treatent of accelerations,or involve [GR]. Not so." In their example, they, like you, also change the TP into a different experiment by saying SR "seems" to imply that either twin can be seen as being "at rest. Then they say yes and no,and that SR's implication is the reason it is a paradox.

Then they say "Bob must change his inertial frame" in order to avoid restating "the problem with [only] the names changed." They do not understand that is what SR says, that either twin can be at rest while the other leaves then returns! Wayne et al seems confused at this point since when they change Bob's frame on the planet, they accelerate him! But Ann is never accelerated wrt to Bob in SR's TP! Clearly, theirs is no longer the same TP experiment, and that invalidates their claims against SR's time dilation effect.

Let's say Bob stays home. The coordinates include earth, Bob, the spaceship, and Ann. All are at rest rest relative to each other. Primary I.F. 2 shows Ann accelerating as she takes off on the ship. P.I.F. 3 shows her return trip to earth. Yes paradox.

    • [deleted]

    A question like "does acceleration affect light clocks?" would definitely make for an interesting discussion, but I don't know if I can quantify anything simple right now to give a yes/no answer. I've come close, by trying a few times to visualize what it would be like for a light clock to travel through a gravitational field, and the one thing that I notice that always automatically pops up is acceleration. I'll try to fiddle around with it some more to see if this acceleration would have a secondary effect.

    I've attached a couple of pictures to illustrate the acceleration effect. The top image shows a light clock where the photon makes a 90 degree change in direction at every tick. The bottom image increases this angle based on height, and so the lower the photon goes, the closer this angle gets to 180 degrees, and the slower time runs. Just following this simple rule, one automatically gets acceleration.Attachment #1: accel.jpg

    Israel,

    Thank you. My hope is to get a discussion going on what all of the existing evidence means and what can be implied by the results of the time dilation experiments to date. I have already read Darly's essay and plan on commenting soon. I have a list of essays to read over the weekend and have added yours and Wagner's to the list.

    Jack,

    Is there something getting lost in translation here? I am still not sure what your issue is with me? A fundamental assumption that I think is wrong is Einstein's explanation for how/why time slows down (and speeds up). I outline what his twin paradox resolution proposes and show what concerns I have with his resolution.

    You appear to be offering solutions that vary from Einstein's resolution and then proceed to call me a crackpot (which I don't mind, I'm used to it).

    So - just so I am clear - are you saying that my account of Einstein's resolution is inaccurate? If so - please elaborate.

    Or are you saying that my specific criticism of Einstein's resolution is inaccurate? If so, please explain what you have an issue with.

    Or do you think I am completely missing your repeated point that there are a number of ways to solve the paradox and since they all arrive at the same mathematical result showing how much the clocks are out of sync, then they are all equally valid?

    I do not question the experimental evidence that time dilation is real. What I am interested in specifically is what the cause or mechanism is for this interesting effect. The more we learn, the more we will learn what "time" really is.

    But the problem with multiple mathematical methods to get the same result is that they can't all be what is truly, physically happening. For example, if I want to find out how the human body synthesizes dopamine from tyrosine using tyrosine hydroxylase and DOPA decarboxylase enzymes, I am specifically interested in which atoms are added, removed or rearranged on the molecules. Sure - I could put some tyrosine in a beaker and show a dozen different ways to synthesize dopamine from it, and they would all be valid obviously, but if my goal is to find out what is happening with this specific enzymatic pathway - then I am looking for a specific step by step explanation. A simpler example would be the police investigating an incident involving a suspect. The lying suspect provides a mathematical timeline that insists he drove 40 mph the long way home and explains a plausible route that puts him nowhere near the scene of the crime. Another more direct route is also mathematically possible where he would have arrived after driving 30 mph - this route would have put him at the scene of the crime. His problem however is that his tire tracks put him at the scene of the crime. When it comes to relativity Jack, I'm interested in the what the tire tracks indicate.

    • [deleted]

    To Garcia:

    The reason for my citing the web site was simple - it was to show how Triplets can remove all acceleration.

    Here is a quote from the cited site that you finally sighted:

    "To avoid accelerations in the thought experiments above, we can simply make the second Bob frame into a 'messenger' Carl that never accelerates, but passes by Bob as they set their watches together. Messenger Carl then travels to Ann and compares watches as they pass each other. That makes it clear that there are three distinct inertial frames involved."

    Please note their key phrase "To avoid accelerations."

    Thomas & Nobody,

    Something to consider: If there is a resolution model that doesn't require acceleration from the POV of the traveler, then that must mean the traveling clock is experiencing a slowing that the Earth clock does not within the confines of inertial motion. And if that is the case - Galileo's Principle goes out the window. That's why Einstein kept the relative clock dilations reciprocal during inertial and required acceleration as a form of simulated gravity to invoke an Earth clock speed up due to difference in gravitational potential. I myself am not opposed to the possibility of Galileo's Principle going out the window.

    G S,

    Thank you for your kind words. I am designating this weekend to play catch-up with all of my reading and I will add your essay to the list. As for your concerns about voting methods and all of that - I plan on reading as many essays as I can. I will vote on the ones that I am confident that I understand but I am not going to discuss who I vote for and how I score. I think if we all did that it would be a better contest. I fear as we get closer to the end, this voting business will become more of a distraction instead of taking advantage of the fact we are all in a virtual room discussing some pretty cool ideas.

    • [deleted]

    Nobody, we already agree there are 3 primary I.F.s. Our point of contention now is my claim that your citation is substituting the author's incorrect understanding of the TP which is not parallel to the TP and thus his is a false analogy to the TP, which makes it an invalid argument by the rules of logic.

    An argument defeated in proper debate is an argument lost. Unless you can show I am wrong in my claim that it is an incorrect analogy to the TP, it remains an invalid argument.

    Your turn, Friend.

      • [deleted]

      Hi, Chris,

      Yep, the clocks do slow differently due solely to their different speeds thru space (inertial motions only), but this does not obliterate Galileo's principle - only Einstein's. (Gal's mechanical relativity still stands, but E's optical rel. falls - but it never held in the first place - so no big loss there!)

      • [deleted]

      To Garcia:

      It really makes no difference what Throop said about the Twin Paradox because that case involves acceleration, which I am trying to avoid, and which can easily be avoided by simply adding a third person. This tells us in no uncertain terms that people age differently even sans acceleration. SR has no explanation.

      Neo-Lorentzian interpretation of relativity is also not justified. I am looking forward ...

      Eckard

      T. Garcia to Nobody:

      Nobody, I can only reply that the TP thought experiment has as its basic premise acceleration in it and if you take that out it is no longer the same experiment. Like if you want to measure the distance between earth & pluto but you can't because pluto is too far away. So you measure the distance to Saturn and say that is the same distance to Pluto.

      Acceleration need not be a speed increase; it can a change of direction or up or down, or a slowing of speed. Acceleration is merely a change in motion. Why would anyone want to take acceleration out of the TP?

      Without it, in fact, there can be no time changes, as per SR's explanation. An object moving at constant speed and direction is at constant velocity, while an object moving in a perfect circle is at constant acceleration.

        T. Garcia to Chris Kennedy 09/13/12

        Like you, Chris, I wonder in my essay why no one had previous to me noticed my essay theme that speed determines the time rates for objects. You wrote a fine piece and included what could be valid arguments for your POV. We have found different viewpoints, however, in that you see the paradox as being the claim that each twin - if they could see each other's clocks - would see the other's clock as running slower. To me, the paradox is the so called "time dilation effect," which is resolved by my claim that time is a property of matter, etc.

        Basics

        A) Yes, I learned long ago A. Einstein (AE) took a lot of ideas from others without always giving credit where due, which often resulted in the public thinking he was not as great a genius as we were taught he was. But I think he was, really, since he maneuvered his way well through the lethal labyrinth of naked emperors who fought fiercely, as some still do, to hold on to whatever status they managed to win by hook or crook.

        B) Here, he gave Galileo some credit. However, the statement that starts out with, "That is, all motion at constant velocity is to be considered relative...." puzzles me because constant velocity here seems out of place. Since all objects are in motion, all motion is relative, not just motion at constant velocity. What is your opinion on that?

        To you, it seems the issue is the way AE concocted his explanations to resolve the TP, when all he had to say is that time is a property of matter and it passes inversely proportional to an object's speed. In order for the spaceship to leave earth and then return to it, it had to speed up. It did not have to turn around if it made a circular round trip, but if it did, the speeding up - relatively to the earth - is necessary to catch with the planet once more. Is that correct, or not?

        The train experiment and others like it support AE's relativity also. So if he made up his math, it would not be the 1st time, but even so, the simplest explanation for any paradox is one like mine, I think, because it does not need any math to confuse the issue. If AE could have done that, we all would have been much smarter faster.

        • [deleted]

        One thing to consider is that if someone is aging faster, ie. has a faster clock rate, they are not traveling into the future more rapidly, but into the past faster. They die sooner. Time is not a measure or dimension from past events to future ones, but the process by which the future becomes the past.

        Knowledge is created inductively, future possibilities condensing into actualities, but it is used deductively, applying past experience to predict the future.

        • [deleted]

        Tom,

        I think it's more the velocity. As in traveling at the speed of light, time is stopped, since there is no internal activity to light, since the combination would exceed C. Acceleration also would slow the clock, ie. equivalence principle, but constant acceleration would quickly reach the speed of light, so that effect would be limited.

        As Chris' essay shows, all these ideas are historically ambiguous and it's only tradition that canonizes them.

        • [deleted]

        To Garcia from absolutely Nobody:

        It's obvious why we need to get rid of all acceleration - this is the only way to simplify the TP so as to preclude any claims that acceleration has anything to do with the age difference.

        Have you never heard of the KISS rule? We do not need overly-complicated examples for cases that are very simple. (This rule should also have been applied by Chris in his essay.)

        Not to remention the fact that acceleration has *no* effect upon either clocks or twins anyway.

        T. Garcia to Nobody:

        Maybe this will help you see it is not acceleration that is needed to see the whole forest. It is needed to cause time dilation. In your Triplet Example, there is no time dilation because there is no acceleration on the part of the three ships in space. For time to "dilate," one ship has to change its speed from that which all three are moving at constant speed. That one ship's time rate will be different than the other two ships.

        The effect of time dilation is a pardox which is clearly stated in the train experiment. There is nothing left to resolve unless one can sccessfully argue the time as measured by each observer is the same. Until then, the imaginary "time dilation" paradox does not exist anymore because we know now how it happens and why: It happens because time is a property of objects and passes inversely proportional to an object's speed.

        • [deleted]

        What train experiment?

        And, sorry to say, but you are simply ignoring all of the facts that I have already presented.

        You wrote:

        >In your Triplet Example, there is no time dilation because there is no acceleration >on the part of the three ships in space.

        No, acceleration is not needed to cause time dilation because

        [1] it cannot because it has zero effect upon clock rates (tested experimentally up to 10^18g) http://math.ucr.edu/home/baez/physics/Relativity/SR/clock.html

        and

        [2] As Throop said, Ann aged differently from Copy-Bob despite the fact that no one accelerated.

        If you cannot digest these two simple facts (not given just by me, but by much more reputable people), then I will have to stop discussing this with you.

        In any debate, one must not discard the facts at hand.

        Daryl,

        Forgive me, I am still trying to get caught up on my responses. Awhile back, you had made this statement: "Schutz' resolution of the "paradox" is consistent with the description that's given according to the special relativistic framework I've set out in my essay."

        At the time, I suspected that it was the same inertial frame shifting resolution that J.A. Wheeler used but I wanted to reread Bernard Schutz' resolution again before I responded. It turns out that it is pretty much the same as wheelers and therefore, unfortunately incorrect.

        If you read my essay, you will know that I am pretty critical of Einstein in two separate areas of his resolution, but I will at least give him some credit for having the courage to answer the critics directly. Einstein maintained his focus on the two objects in question and during the turnaround he claimed that a difference in gravitational potential for the two objects and their clocks (and not their "frames") was what was responsible for the Earth clock speeding up during that time.

        I won't get into the myriad of resolutions that others have tried except to say that the Wheeler-Schutz explanation uses a physical object to "Transfer inertial frames" and therefore will most certainly experience simulated gravity anyway. At one point Schutz says (regarding the turnaround): "Effectively, Diana sees Artemis age incredibly quickly for a moment." And at some point later, Schutz said: "She (Diana) expects Artemis to have aged much less, but to her surprise, Artemis is a wizened old prune, a full 50 years older!"

        - So before the passage was over, Schutz appeared to confuse himself on what Diana would see along the way. Not uncommon. I think it was Judge Judy who said that if you are telling the truth, you don't have to have a good memory. In any event - this is the minor issue I have with Wheeler and Schutz. The major issue is obviously the part they have in common with Einstein - the inertial part of the trip (before the reported frame shift occurs) which endorses the reciprocal time dilation effect that the GPS system shows to be invalid.

        • [deleted]

        Hi Chris,

        I have taken up your call to all cranks and crackpots willing

        to take on this challenge.

        I went after some low hanging fruit, you will like it.

        See: http://www.fqxi.org/community/forum/topic/1403

        There is a lot of stuff that need to be reconsidered, thanks for reminding us.

        Don L.