Graystar

Are you guys serious??? Twice I've written, "what does 1 ST in space-twin's frame equal in platform-twin's frame?" ...and you guys are still asking what frame??? Forget it.

Neither. I'm asking about the transformation. There's space-twin's frame on one side of the equal sign, and platform-twin's frame on the other. I gave one transformation that we all agree upon, 1/2 sec in space-twin's frame equals 1 sec in platform-twin's frame. So the question is what does 1 ST in space-twin's frame equal in platform-twin's frame?

Okay, lets do it this way. The twins are on a platform in space. There’s another platform one meter away. Space-twin instantly accelerates to 0.8666c towards the other platform. Space-twin’s body is facing the platform and, of course, has a depth to it. Lets call that depth 1 ST. So lets try this again. If space-twin needs 1/2 a tick of his clock to move forward in time one tick of platform-twin’s clock, wouldn’t we also say that he has to travel two STs to move forward one PT?

I'm sure space-twin would reply, “why is my ship, at rest, compressing?” There's this notion going around that if you feel acceleration you must be moving. I’ve read that about the twin paradox as well. There’s also the notion that the Earth really is moving because it has been flattened slightly due to spinning. That’s so ridiculous as to be laughable. If you’re standing on Earth, holding onto a rope connected to the Sun, and then the Earth moves away from you and the Sun, you’re going to feel acceleration even though you’re not moving! Don’t believe me? What do you think the tide is? It’s the moon’s gravity tugging at matter as it moves away. If the Earth were pliable enough it would be flattened along the orbit of the moon, in the same way that it’s flattened due to “spinning.” But we don’t say the Earth is moving relative to the moon, do we? That’s the primary problem with the twin paradox...this idea that acceleration proves one is moving. What boggles my mind is how people who believe relativity can also believe that one twin is absolutely moving. Don’t they know everything is relative??

Janus’s response... “The effects due to gravity are irrelevant to this observation.” ...was in response to my comment which started... “Yes, but the muons, as well as the clocks flown around the world...” So if Janus’s response was referring to muons only then that would have been clarified in the post. But it wasn’t. So my presumption is that Janus was referring to the airplanes as well. If that’s wrong, Janus is perfectly capable of clarifying that point for me. Well if you really want to get into the details, the test was done with 4 clocks, all of which were flown in one direction and then the other. In each flight, at least one clock changed in the opposite direction of what was predicted, and this was after the clocks measured drift rates were accounted for (interestingly, the clock that was closest to the predicted eastward dilation, also dilated westward.) Hafele & Keating performed two rounds of corrections to get the clock data to agree with the predicted results. A. G. Kelly didn’t agree with the results...but there are always detractors. What concerns me more is that the guy who created the clocks, Louis Essen, didn’t think they were accurate enough to perform the experiment. Considering that 138ns was the closest any clock got to the predicted 275ns westward drift, and that the spread between the actual slowest and fastest westward results was 457ns, I’d say the expert is probably right. The clock mentioned above, which was closest to the predicted eastward value, was off the most from the westward value by 319ns. So if you’d like to discuss the selective ignorance of evidence, I’d be happy to discuss the fact that the true clock results were anywhere but on target. The NPL recreated the experiment and said it works. However, I haven’t been able to find the actual data. There doesn’t seem to be a link to it on their website. Correct. That was my point. That comparing an experiment based on both SR and GR, to a thought experiment based on SR only, makes no sense. So when I bring up an issue in an SR experiment, it makes no sense to counter with points from an SR+GR experiment. That’s what I meant when I said, “Yes, but the muons, as well as the clocks flown around the world, where also subject to gravity and its effects. The version of the Twin Paradox that I am questioning refers to SR only.” Apparently, that wasn’t clear enough. Merged post follows: Consecutive posts merged Well, lets forget about the “crackpot”. If you would care to continue this discussion, I would rather spend time trying to get you to sense that something is wrong with the way the twin paradox is laid out. It makes no sense for me to explain any sort of corrected result from a slightly different viewpoint if you’re not yet willing to consider that viewpoint. I’d like to refer back to space-twin’s spaceship, which I made 4.45 LY long. Lets say that Earth-twin has an identical spaceship. This ship doesn’t go anywhere in the experiment...it just sits there. So space-twin starts on his trip. Space-twin’s time, as observed, slows. Also, space-twin’s ship, as observed, is half its resting length, or 2.23LY long. If space-twin needs 1/2 a tick of his clock to move forward in time one tick of Earth-twin’s clock (regular ol’ accepted time dilation) wouldn’t we also say that he has to travel two lengths of his ship to move forward one length of earth-twin’s ship?

No they’re not. If you had reviewed the data from the flight of the atomic clocks you would have known that the clock was running faster at the end of its trip (the expected outcome.) But I suspect you simply scanned the results. I’ve noticed a lot of scanning around here. Maybe if you fully read things you’d be better equipped to understand the theories proposed, and be able to properly articulate why the theory is wrong. That would be a little more helpful than “I scanned it...he’s a crackpot and you’re wrong.” I wouldn’t call the guy a crackpot since his formulas give the same exact answers that Einsteinian relativity does. You can use his formulas to design the GPS system and you’d get the same exact system that’s in place now. The only difference between the two theories is the reason why all this happens (wave theory of matter and the existence of aether vs. shrugged shoulders.) Personally, I think he’s likely right, but Einstein’s way is easier for me to work with so that’s what I’m sticking to. And Einsteinian relativity tells me the twins are the same age. Oh...it also tells me that the passenger on the moving train sees the lightning bolts strike the ends of the train at the same time, just like the observer on the platform. But that’s another story.

Yes, but the muons, as well as the clocks flown around the world, where also subject to gravity and its effects. The version of the Twin Paradox that I am questioning refers to SR only. In any case, I think I have found the explanations I was looking for on the follow web page (pages) http://www.glafreniere.com/matter.htm So I'm going to study those pages for a while to get a better understanding of the theories proposed. Thank you everyone for your answers.

So he gets into his ship and instantly accelerates to .8666c. Earth is behind him, so the star is now at (or slightly past) the middle of his ship? That would mean that the star moved from the front end of his ship to the middle of his ship instantaneously and that a passenger sitting in the middle of the ship would now be at the star. I wish people would stop saying “you’re wrong, this is how it is,” and simply apply my view to some other situations and demonstrate that it comes up with the wrong answer.

According to the clock postulate acceleration has no effect. “The clock hypothesis states that the tick rate of a clock when measured in an inertial frame depends only upon its velocity relative to that frame, and is independent of its acceleration or higher derivatives.” Here are some links to it. http://math.ucr.edu/home/baez/physics/Relativity/SR/clock.html http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html Merged post follows: Consecutive posts merged That’s right. That’s wrong. Say that space-twin is at rest with Earth-twin on Earth. The star is 4.45 LY away. Space-twin now gets into his ship, which, coincidently, is 4.45 LY long (it’s a big ship.) Now space-twin speeds up to .8666c. How long does space-twin measure his ship to be? Is it 2.23LY long or 4.45 LY long? If what you say is true... “There is no difference between what he measures and what is.” ...then he will measure 4.45LY, and that’s what is. In his frame, traveling to the star, the distance is still 4.45LY (the front of his ship is already there!) Space-twin does not experience contraction, just like he doesn't experience time dilation. Those phenomena are merely observed from a different frame. His ship appears to be 2.23LY from the other frame. But to space-twin, his ship appears to be 4.45LY long, and his clock appears to be running normally, and his speed appears to be .8666c, and he will experience a trip time to the star of 5.14 years.

Okay, one more This is the error that I believe has been made for so long. Yes, space-twin measures the Earth-star contraction as 2.23LY. But that doesn’t make his trip 2.23LY. This is as simply as I can put it. If we, at rest, want to measure one second of contracted time, our resting clock needs to tick for one-half seconds. If we want to measure 2.23LYs of contracted distance, our resting distance must be 4.45LYs. When the moving star arrives at space-twin, we say that, during the trip, Earth-star experienced one second for every two seconds experienced by space-twin. In the same exact way, we must also say that, during the trip, for every yard experienced by Earth-star, space-twin experienced 2 yards. When the star arrives at space-twin, the tape measure that space-twin hooked on the Earth before it left will read 4.45 LY.

“The ratios between different lengths does not hold between reference frames.” If you’re saying that you don’t take a property from one frame (like a half-ticking clock) and apply it in another frame...yes, ratios don’t hold between frames. “They are symmetrically and oppositely modifed.” Yes. “For example, each twin sees himself as twice the height of the other.” When standing along the direction of travel...yes. “Treat the Earth and destination star, at rest relative to one another, as a single object, with a dimension of 4.45ly. To the same degree that the space twin sees his brother contract, earth-star contracts as well.” Yes. “Earth twin sees the ratio between earth-star and space twin double” One ET meter to two ST meters...yes. “while space twin sees that same ratio cut in half.” One ST meter to two ET meters...yes. But lets go back to the first thing you said... “The ratios between different lengths does not hold between reference frames.” When the frame at rest notes time dilation in the frame in motion, rest-frame doesn’t start considering moving-frame’s time in its own activities, does it? Rest-frame doesn’t say, “hey my trip was 5 seconds, not 10, because I like using moving-frame’s clock to measure my time.” We don’t apply dilation to the resting frame. Why then would we apply moving-frame's contraction to the resting frame? Why, upon seeing Earth-star contract, are we so willing to say, “hey my trip was 2.23LY, not 4.45, because I like using moving-frame’s contraction to measure my space.” That seem inconsistent to me. As you said, ratios don’t hold across frames. Well, I think at this point we’re approaching “going in circles”, so I will leave it to your last response (if you desire to make one.) But thanks for providing challenges to my view (which is always for a person to provide to himself.) It was a good exercise for me to apply my theory to the situations suggested.

Well, the symmetry of my explanation would apply acceleration effects symmetrically, but I believe that takes us out of the realm of special relativity, and I didn’t want to go there. That’s why, when I laid out the original parameters, I said acceleration is considered instantaneous. But I know sometimes you just have no choice but to go in a certain direction to get the right answer, and that seems to be the case here. So I know that, ultimately, I may be left having to understand more that I can about the scenario. But we do this anyway. Don’t we? We say that if space-twin’s ship is 100 meters long when at rest with Earth-twin, then Earth-twin sees the ship contract to 50 meters long when moving at 0.8666c. But we don’t change how space-twin sees his ship. Space-twin still sees his ship as 100 meters long. That view is fully accepted. All I’ve done is simply extend that view beyond the ship. If a distance, viewed by Earth-twin as 50 meters, is measured by space-twin to be 100 meters, doesn’t it follow that a distance measured by Earth-twin to be 4.45 LY would be measured by space-twin to be 9.9 LY? Another way of posing this question...why would we limit contraction to the limited space of space-twin’s ship? What about the 100 meters in front of the ship? How does space-twin see that? And just as important a question, how does Earth-twin view the 100 meters that space-twin views? Shouldn’t the space in front of the ship (and behind the ship) follow the relativistic views applied to the space that the ship itself occupies? Shouldn’t all space in the direction of space-twin’s motion be contracted? Ah, that’s exactly what I said doesn’t happen. Space-twin doesn’t see himself traveling 9.9LY, anymore than he sees his clock ticking slower or his ship being 50 meters long. Space-twin sees himself traveling to a star 4.45 LY away, in normal time, in a normal ship, at 0.866c. It is Earth-twin who sees, when compared to his own space, a space-twin clock ticking slower, a space-twin ship getting shorter, and a space-twin distance to the star getting longer. And thanks for trying to explain (I did notice that the hand-smacking-the-head smile is first on the list! )

Thanks for responding! Yes, I agree. I’m just trying to understand what’s wrong with it. That said, I think the points you raised can be addressed with more clarity on my view, without having to change my view. Especially on the issue you raise first… Absolutely correct, of course. The issue I raise, though, is why do we use 4.45 light-years, a measure from a different frame of reference, to determine space-twin’s distance to the star. Space-twin is in a different frame. Time is different...why should distance (or more appropriately, space) be the same? The situation that I’m explaining is that of noting a difference in another frame, while maintaining your own frame. We already accept this with time. The clock in our frame ticks at one rate, but we note that the clock in another frame ticks at a different rate. What I’m saying is that this same exact view must also apply to contraction. Earth-twin sees the distance to the star as 4.45 LY, and, within his frame, will see the ship travel 4.45 LY. But just as Earth-twin notes that time is ticking slower for space-twin (although Earth-twin cannot experience that,) Earth-twin also notes that space-twin is traveling 9.9 LY (although Earth-twin cannot experience that.) Doh! Didn’t say that! Earth-twin simply notes that space-twin’s yardstick is shorter. In the accepted solution, Earth-twin experiences 10.28 years while space-twin experiences 5.14 years. Why? Because there’s a ratio between the two frames...two Earth ticks for every tick on the ship. All I’m saying is that the same must apply to contraction. There’s a ratio between the two frames...one Earth yard for every two yards on the ship. What I’m also saying is that this contraction must also be applied to space-twin’s entire universe (in the direction of travel, of course.) Space-twin see his trip to the star as 4.45 LY, not 9.9LY, just as a tick of his clock feels like a normal tick to him. Meanwhile, Earth-twin sees a slow tick occurring (as related to himself) as well as a longer distance (as related to himself.) That’s why Earth-twin would not determine space-twin’s speed to be 1.7c...space twin is going further, but his clock is going slower as well. From Earth-twin’s point of view, space-twin would measure speed to be 0.8666c (in his own frame) and distance to be 4.45 LY (in his own frame.) From Earth-twin’s point of view, space-twin experiences half as many ticks, and twice as many yards. Anyways, I thought it was an interesting and different way to look at the situation. Thanks for your comments! Merged post follows: Consecutive posts merged I was referring to the accepted solution when the frame is switched and the traveling twin is now the twin at rest. The distance between Earth and star is contracted, and that's the reason for the trip time to be 5.14 years. But if Earth is in motion, then Earth-time must also be dilated. Earth's time dilation is like the uncle is prison...everyone knows about it but no one talks about it. The traveling twin's contraction is like a night of heavy drinking...no one remembers it at all!

I'm just a layman and I don't know what I'm talking about! (Just thought I'd clear the air on that point In any case, I think I've solved the twin paradox. However, being someone who doesn't know what he's talking about, I'm sure there's something wrong with my conclusions. I hope someone will gently point out where the mistake is. Here's my conclusion...when the traveling twin arrives back on Earth he will be the same age as the twin that stayed behind. And how did I arrive that this conclusion? By applying the two relativistic effects that seem to be ignored in all versions of this thought experiment that I've read...Lorentz contraction of the traveling twin, and time dilation of the Earth. I'll quickly reiterate the experiment just so everyone knows the version I'm working from. This is the Wikipedia version and I've read it in other places as well. Only special relativity is considered. Twins on Earth; star 4.45 light years away; one twin travels at 0.8666c towards star then comes back; acceleration/deceleration, as well as turnaround, assumed to be instantaneous. So the story goes... From the point of view of the twin on Earth, a trip to the star and back at .8666c takes 10.28 years. So the twin in the space ship is away for 10.28 years. However, time dilation comes into play and we see his time slow down by a factor of .5 so he only ages 5.14 years. Meanwhile, from the point of view of the twin in the ship, another relativistic effect, Lorentz contraction, comes into play. He sees the distance to the star as being only 2.23 light-years. Being at rest in his frame of reference, he sees the star zoom up in 2.57 years and then zoom away for 2.57 years. Total trip time...5.14 years, and we have consistency! It's a nice sounding story, but methinks it's wrong. Why? Well, from the Earth-twin's PoV, what of Lorentz contraction of the traveling twin? And from the space-twin's PoV, what of time dilation of Earth. As best as I can tell, the contraction of the space-twin is completely ignored in all solutions. This is the critical mistake. Likewise, dilation of time on Earth is mentioned, sometimes, but also seems to be ignored. But dilation of time on earth is critical for bringing consistency to my new view, which considers the contraction of the space-twin. So here we go! The ground rules (or... it's all for naught if I don't have the basics right!) When we say that time slows down for an object in motion relative to an observer at rest, we mean that time really does slow down...it's not an optical illusion. So what does that mean for Lorentz contraction? It means the same thing...that the object doesn't simply look contracted. It really is shorter in the direction of motion. Nothing new there. How about this...what times are we comparing when we say an object is time dilated? We are comparing the actual time of the observer at rest vs. the actual time of the object in motion, as perceived by the observer at rest. So what about Lorentz contraction? What are we comparing? The actual length of the observer at rest vs. the actual length of the object in motion, in the direction of motion, as perceived by the observer at rest. Again nothing new there. This thought experiment isn't about coming up with anything new. I'm simply properly applying what we already know. So lets apply these relativistic effects properly. First up is the point of view from the twin on Earth, who we will call Earth-twin. Earth-twin is at rest, and his twin, who we'll call space-twin, is the twin in motion. Earth-twin sees space-twin flying off at 0.8666c. From Earth-twin's point of view, space-twin's time rate is cut in half...their clocks are truly ticking at different rates. This everyone knows. But something else has also changed. Space-twin is Lorentz contracted. From Earth-twin's pov, space-twin is truly shorter in the direction of travel. Why is this important? Because it changes space-twin's distance to the star in the same exact way that his clock rate is changed. According to Earth-twin, space-twin's distance to the star is not 4.45 light-years, but 9.9 light years! This is perfectly consistent. In the same way that we easily accept two clocks in different frames ticking at different rates, we should also be willing to accept that two observers in different frames will perceive the same space differently. In fact, in what I call the classical solution, the analysis of the space-twin starts off with the distance between Earth and star cut in half! So we shouldn't have a problem with space-twin's distance being different. The question is...why 9.9 light-years? Just as time has slowed for space-twin (because space-twin's slow clock is being compared to earth-twins faster clock,) distances have increased for space-twin (because space-twin's yardstick is shorter than Earth-twin's yardstick.) Space-twin, who still thinks his yardstick is one yard long (because it really is…to him ) has to measure two yards for every Earth-twin yard! (Remember, we're comparing the contracted yardstick to Earth-twin's at-rest yardstick, just as we compare space-twin's dilated time to Earth-twin's at-rest time. It's all about Earth-twin's reference frame.) NOW we have all that we need to properly determine space-twin's experience. The space that Earth-twin sees as 4.45 light-years is experienced by Space-twin as 9.9 light years due to his yardstick being half as long as Earth-twin's yardstick. Space twin is traveling at 0.8666c, so the trip to the star takes 5.14 light-years from Earth-twin's pov, while Earth-twin sees space-twin experience a trip distance of 9.9 light-years to the star and a trip time of 10.28 years. The trip back is exactly the same. And...since time dilation and Lorentz contraction go hand-in-hand, space-twin's clock only ticked half as many times throughout the trip. Space-twin experienced 10.28 years of time, as determined by Earth-twin (who is at rest.) Also, Since Earth-twin saw space-twin fly to a star 4.45 light-years away at 0.8666c and back again...he experienced 10.28 years as well. Stated another way, in the same way that Earth-twin feels normal time passing (a tick is a tick), but also sees that space-twin is experiencing dilated time (a space-twin tick is two Earth-twin ticks,) Earth-twin sees his normal space (a yard is a yard) but also sees that space-twin is experiencing contracted space (a space-twin yard is half an Earth-twin yard.) Since twice as many space-twin yardsticks are need to measure Earth-twin's distance to the star, it follows that space-twin must travel twice as far. This makes sense because in the examination of space-twin we will contract not only the Earth and star, but the space in between. From Earth-twin's view It would seem inconsistent to contract the moving space ship and nothing else. For consistency, we must contract the distance the ship travels as well. Now it's space-twin's turn to take a rest and see how all objects move in relation to him. A resting space-twin sees the earth moving away at 0.8666c and the star moving toward him at 0.8666c. From space-twin's frame, the distance between the Earth and the star is 2.23 light-years, right? Wrong. It's 4.45 light years. The root of this long-standing mistake is that the value of 2.23 light-years is derived from 4.45...which was taken from outside the reference frame. That is, the value, 4.45 light-years, came from the Earth-twin's resting frame. But as soon as Earth starts moving, space-twin is outside of that frame and he experiences the same space and time differently. So why would space-twin use, in his calculations, a value from Earth-twin's frame? The space that equals 4.45 light-years in Earth-twin's frame must have a different value in space-twin's frame. And I don't mean the Lorentz contacted space... I mean the space used to later calculate the Lorentz contracted space. As soon as space-twin started moving, the value of 4.45 light-year distance becomes meaningless because it's from a different frame. There must be a complementary value in space-twin's frame that represents the same space in Earth-twin's frame. In fact, we've already calculated the complementary value. When discussing the point of view of Earth-twin, we calculated that space-twin experiences Earth-twin's space of 4.45 light years as 9.9 light years. So when we switch to space-twin's frame, the Lorentz contracted distance should be calculated from 9.9 light-years., giving a contracted distance between the Earth and star of 4.45 light years. From this point the rest is academic because the situation is now fully symmetrical. From space-twin's pov, Earth-twin experiences the same time dilation, contraction, and lengthening of distance that space-twin experienced previously. The result is as before...both space-twin and the Earth-twin experience 10.28 years of time passing. Now, not only are we consistent, but sensible as well! (one twin aging more than another...I mean really, who's ever heard such nonsense?! ) At the very least, it's different. Remember, be gentle