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Thread: Which clock is the one moving in special relativity?

  1. #1 Which clock is the one moving in special relativity? 
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    In SR, it is the "moving clock" which slows down, right? If object A and object B are approaching (or receding from) each other at, say, .5c, how do you know which clock is moving (and has therefore slowed down)?

    If, for example, we fill up a rocketship with fuel, and ignite it, is there any reason to suspect or believe that, upon ignition, the ship remains absolutely motionless while the earth is pushed away from it at high speed? If not, then why would any passenger on the ship claim that he is "at rest," as SR requires?
     

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    Janus: I am new to this forum and have a number of questions about SR. At this point I have not read your entire primer, or all the posts in this thread, for that matter. I'm just kinda asking questions as i go. Early in your primer you say:



    "Example, going back to our astronauts A and B. Assume that their relative velocity is towards each other (A see's B approaching him and B see's A approaching him)."

    Question: When you say "sees," you don't mean that literally, right? Neither A nor B "sees" who is approaching who with their eyeballs or instruments, correct? What you really mean is that both A and B assume that they are motionless and that it is always the "other guy" who is moving. This assumption is mandatory in SR, correct?
     

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    Quote Originally Posted by Layman View Post
    In SR, it is the "moving clock" which slows down, right?
    Nope. Wrong.

    If object A and object B are approaching (or receding from) each other at, say, .5c, how do you know which clock is moving (and has therefore slowed down)?
    Both clocks tick at 1 second per second. You have some basic misunderstandings about relativity.
     

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    I can't seem to get the quote function to work, sorry.

    Andrew, you say: "You have some basic misunderstandings about relativity.'

    OK, what have I misunderstood? Are you saying clocks do not slow down with speed, according to SR (and many experiments)?
     

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    Janus, I've now read most of your primer, and see that you say:

    'At this point I would like to reiterate the concept of "no preferred frame". Even though the two frame come to different conclusions as whether or not the clocks show the same time, each is equally entitled to his conclusion, and there is no absolute way to say who is "really" right."

    In a later section you address the twin paradox. As I understand it, according the the theory, the space twin "really" does age more slowing, and it's not all just a matter of subjective perception, right?
     

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    Quote Originally Posted by Layman View Post
    I can't seem to get the quote function to work, sorry.

    Andrew, you say: "You have some basic misunderstandings about relativity.'

    OK, what have I misunderstood? Are you saying clocks do not slow down with speed, according to SR (and many experiments)?
    Clocks DO NOT "slow down". You do not understand SR. You should read the primer, take a class, your misunderstandings cannot be resolved in this forum.
     

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    Back to this quote:

    'At this point I would like to reiterate the concept of "no preferred frame". Even though the two frame come to different conclusions as whether or not the clocks show the same time, each is equally entitled to his conclusion, and there is no absolute way to say who is "really" right.'

    While SR claims that there is no preferred frame, the theory actually basically posits that every observer is in his own motionless "preferred frame" and is, in essence, an ether to himself, right? Anything and everything is the universe which is moving relative to him is "moving," while he is "stationary," right?

    Put another way, in SR any given observer is strictly prohibited from assuming that he is the one moving. It MUST always be the other guy who is moving, right? The whole theory would fall apart if both A and B agreed that B was the one moving. That can't be allowed. They are REQUIRED to disagree about who is moving, correct?

    The "preferred frame" is always the one you happen to be in. There are an infinite number of these preferred frames, of course, when looked at collectively, but no observer in SR ever seems to acknowledge this. The "stationary" frame is always the one he is in, as far as he's concerned, and the possibility that the "other guy" is stationary and that he is the one moving is not just ignored, but flatly denied, best I can tell.
     

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    You say: "Clocks DO NOT "slow down". You do not understand SR. You should read the primer, take a class, your misunderstandings cannot be resolved in this forum."

    Are you saying that in the infamous "twin paradox" one twin DOES NOT age more slowly, and that both end up having aged the same when they re-unite?
     

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    Quote Originally Posted by Layman View Post
    You say: "Clocks DO NOT "slow down". You do not understand SR. You should read the primer, take a class, your misunderstandings cannot be resolved in this forum."
    Correct. This is exactly what I am saying.

    Are you saying that in the infamous "twin paradox" one twin DOES NOT age more slowly, and that both end up having aged the same when they re-unite?
    The twin that does the "turnaround" ages slower but this is not because his clock is ticking any slower. His clock is ticking at exactly one second per second. You WILL NOT learn relativity by posting here, this is not the proper way to learn. Take a class.
     

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    "The twin that does the "turnaround" ages slower but this is not because his clock is ticking any slower. His clock is ticking at exactly one second per second."

    All the experts I've read disagree with you. ALL physical processes slow down with speed and that includes the ticking of clocks. What is the standard for the self-same "one second" you keep referring to? One second as measured in Lorentz's ether, or what? Or are all these putatively "identical" seconds of different duration for each inertial frame of reference?

    ----


    "You WILL NOT learn relativity by posting here, this is not the proper way to learn. Take a class."

    You're quite presumptuous and condescending, aren't you? Too bad you can only make unsupported, unreasoned raw assertions in lieu of a rational explanation which would display your ultra-superior understanding, eh?

    By the way, before it was turned into the "twin paradox," it was the "clock paradox." Einstein himself posited that clocks slow down with speed (following Lorentz and Poincare). That was in 1905. Did you know that? Apparently not.

    "In his famous paper on special relativity in 1905, Albert Einstein deduced that when two clocks were brought together and synchronized, and then one was moved away and brought back, the clock which had undergone the traveling would be found to be lagging behind the clock which had stayed put."

    https://en.wikipedia.org/wiki/Twin_paradox
     

  11. #11  
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    Quote Originally Posted by Layman View Post
    "The twin that does the "turnaround" ages slower but this is not because his clock is ticking any slower. His clock is ticking at exactly one second per second."

    All the experts I've read disagree with you.

    You don't understand what you are reading. The clocks DO NOT "tick slower", the twin paradox is due to differences in total elapsed proper time, not due to differences in "tick rate". The total elapsed proper time is a function of the twin's path through spacetime, the longer the path, the shorter the total elapsed proper time.

    ALL physical processes slow down with speed and that includes the ticking of clocks.
    You seem to have an agenda of propagating crackpottery. This is a mainstream science forum, cease and desist.




    One second as measured in Lorentz's ether, or what?
    There is no such thing.


    Or are all these putatively "identical" seconds of different duration for each inertial frame of reference?
    One second measured by the clock. Take the recommended class.

    ----


    "You WILL NOT learn relativity by posting here, this is not the proper way to learn. Take a class."

    You're quite presumptuous and condescending, aren't you. Too bad you can only make unsupported, unreasoned raw assertions in lieu of a rational explanation which would display your ultra-superior understanding, eh?
    Take the class, you will be taught proper science.

    By the way, before it was turned into the "twin paradox," it was the "clock paradox." Einstein himself posited that clocks slow down with speed (following Lorentz and Poincare). That was in 1905. Did you know that? Apparently not.
    Clocks DO NOT "slow down". Stop pushing crank concepts, this is a mainstream science forum.

    "In his famous paper on special relativity in 1905, Albert Einstein deduced that when two clocks were brought together and synchronized, and then one was moved away and brought back, the clock which had undergone the traveling would be found to be lagging behind the clock which had stayed put."

    https://en.wikipedia.org/wiki/Twin_paradox
    True enough. Nothing to do with any clock "slowing down". Take an intro class to relativity.
     

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    'You seem to have an agenda of propagating crackpottery. This is a mainstream science forum, cease and desist.'

    Heh.

    "Mainstream science." eh?

    "The clocks DO NOT "tick slower", the twin paradox is due to differences in total elapsed proper time, not due to differences in "tick rate". The total elapsed proper time is a function of the twin's path through spacetime, the longer the path, the shorter the total elapsed proper time.'

    A path through space time is merely a geometrical-mathematical abstraction, not a time-keeping piece, as Einstein said. Clocks do "tick slower" according to many, if not all, of the mainstream theoretical physicists, including Albert, of course. Clocks measure time, "paths" don't, I'm afraid.
     

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    Quote Originally Posted by Layman View Post

    A path through space time is merely a geometrical-mathematical abstraction, not a time-keeping piece, as Einstein said. Clocks do "tick slower" according to many, if not all, of the mainstream theoretical physicists, including Albert, of course. Clocks measure time, not "paths."
    The total elapsed proper time is a FUNCTION of the path thru spacetime. Take the intro to relativity class.
    This is illustrated clearly on the wiki page on the twins paradox that you just cited. You would see that if you had any capability of reading and comprehending.
     

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    "True enough. Nothing to do with any clock "slowing down". Take an intro class to relativity."

    It's actually rather startling that you can purport to agree with Einstein's statement about clocks "lagging behind," while claiming the exact opposite of what he said.
     

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    Quote Originally Posted by Layman View Post
    "True enough. Nothing to do with any clock "slowing down". Take an intro class to relativity."

    It's actually rather startling that you can purport to agree with Einstein's statement about clocks "lagging behind," while claiming the exact opposite of what he said.
    "Lag behind" means accumulating less proper time. Do yourself a favor, stop trolling and take that class. See if you can comprehend this:
    https://en.wikipedia.org/wiki/Twin_p...pacetime_paths
     

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    "This is illustrated clearly on the wiki page on the twins paradox that you just cited.."

    Really? Did you even read it? Did you see the chart entitled "Readings on Earth's and spaceship's [B]clocks[/B]?"

    Followed by this text: "No matter what method they use to predict the clock readings, everybody will agree about them. If twins are born on the day the ship leaves, and one goes on the journey while the other stays on Earth, they will meet again when the traveler is 6 years old and the stay-at-home twin is 10 years old.'
     

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    Quote Originally Posted by Layman View Post
    "This is illustrated clearly on the wiki page on the twins paradox that you just cited.."

    Really? Did you even read it?
    Yep, I wrote large sections of it.


    Did you see the chart entitled "Readings on Earth's and spaceship's [B]clocks[/B]?"

    Followed by this text: "No matter what method they use to predict the clock readings, everybody will agree about them. If twins are born on the day the ship leaves, and one goes on the journey while the other stays on Earth, they will meet again when the traveler is 6 years old and the stay-at-home twin is 10 years old.'
    Nothing to do with clocks "ticking slower". I do not think that a class would be beneficial, you are incapable of learning.
     

  18. #18  
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    Quote Originally Posted by Layman View Post
    In SR, it is the "moving clock" which slows down, right?
    Wrong, SR doesn't say such a thing. But you have amply demonstrated that you are unwilling to learn.
     

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    ."Lag behind" means accumulating more proper time."

    In this case, I think you meant accumulating less proper time, not more. The elapsed time is indicated by the respective clock readings, not abstract theory. You don't seem to be capable of making that crucial distinction (between mathematical calculations and physical objects, such as clocks, I mean.).
     

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    Quote Originally Posted by Layman View Post
    ."Lag behind" means accumulating more proper time."

    In this case, I think you meant accumulating less proper time, not more. The elapsed time is indicated by the respective clock readings, not abstract theory.
    The theory (SR) predicts the outcomes. The outcomes agree with the theory. You DO NOT understand the theory.


    You don't seem to be capable of making that crucial distinction (between mathematical calculations and physical objects, such as clocks, I mean.).
    You should quit trolling. You came here with an agenda and it turns out that you have simply exposed your ignorance about SR.
     

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    Ever hear of the Hafele-Keating experiments where actual clocks were taken aboard moving airplanes? Heard of the GPS, and how adjustments are made to clock ticking rates to achieve snycronization?

    Ever hear of Don Kochs from the Baez website? Like everyone else he says, for example, that:

    "A commonly heard phrase in the realm of special relativity is "Moving clocks run slowly". But—even in the context of special relativity—is it always true? The answer is no. It's only true when a clock's ageing is measured in an inertial frame. "

    Do moving clocks always run slowly?

    You strike me as being quite long on bombast and bluster, but rather short on rational explanation, eh?
     

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    You say: "The theory (SR) predicts the outcomes. The outcomes agree with the theory. You DO NOT understand the theory."

    But that is precisely what did NOT happen in the Hafele-Keating experments, the GPS system, recent experiments done with stationary clocks located in various European cities and various other empirical experiments.

    In each case, applying strict SR gave the WRONG predictions. The only type of theory which could accurately predict what observed clocks would actually read was a theory adopting absolute simultaneity rather than the relative simultaneity of SR. That involves establishing a preferred frame for the "master clock" such as the ECI.

    Are you aware of that?
     

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    What HAS been confirmed to a high degree of accuracy is the validity of the lorentz transformations, not SR. Of course those formulas were crafted by Lorentz, et al, when using a theory positing absolute simultaneity. The LT are NOT the exclusive province of SR. In fact, Einstein just lifted them whole cloth from Lorentz and Poincare. He did not invent them.

    Unlike SR, their predictions are good in ALL frames of reference, not just inertial ones--which comes in handy because it's hard to find a truly inertial frame in this universe.
     

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    As I've already said, virtually every theorist on the planet disagrees with your assertion about time dilation having nothing to do with the tick rate of clocks. Here's a brief excerpt from another wiki article on the subject, which you may want to peruse:

    "Special relativity indicates that, for an observer in an inertial frame of reference, a clock that is moving relative to him will be measured to tick slower than a clock that is at rest in his frame of reference. This case is sometimes called special relativistic time dilation."


    https://en.wikipedia.org/wiki/Time_dilation
     

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    Quote Originally Posted by Layman View Post
    Ever hear of the Hafele-Keating experiments where actual clocks were taken aboard moving airplanes? Heard of the GPS, and how adjustments are made to clock ticking rates to achieve snycronization?

    In both cases the disparity between the accumulated proper time is due to the fact that the clocks traverse different paths through spacetime. NOT due to one clock "ticking more slowly". Since you have difficulty learning the basics click here

    As I've already said, virtually every theorist on the planet disagrees with your assertion about time dilation having nothing to do with the tick rate of clocks
    The disparity in accumulated proper time has nothing to do with clock tick rate. (see link). It has to do with clocks counting different number of ticks.

    Ever hear of Don Kochs from the Baez website? Like everyone else he says, for example, that:

    "A commonly heard phrase in the realm of special relativity is "Moving clocks run slowly". But—even in the context of special relativity—is it always true? The answer is no.
    The answer is NO. I explained why. You can quit trolling now.
     

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    Quote Originally Posted by Layman View Post
    You say: "The theory (SR) predicts the outcomes. The outcomes agree with the theory. You DO NOT understand the theory."

    But that is precisely what did NOT happen in the Hafele-Keating experments, the GPS system, recent experiments done with stationary clocks located in various European cities and various other empirical experiments.

    In each case, applying strict SR gave the WRONG predictions. The only type of theory which could accurately predict what observed clocks would actually read was a theory adopting absolute simultaneity rather than the relative simultaneity of SR. That involves establishing a preferred frame for the "master clock" such as the ECI.

    Are you aware of that?
    ...and the crackpot agenda comes out!
     

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    Quote Originally Posted by Layman View Post
    What HAS been confirmed to a high degree of accuracy is the validity of the lorentz transformations, not SR. Of course those formulas were crafted by Lorentz, et al, when using a theory positing absolute simultaneity. The LT are NOT the exclusive province of SR. In fact, Einstein just lifted them whole cloth from Lorentz and Poincare. He did not invent them.

    Unlike SR, their predictions are good in ALL frames of reference, not just inertial ones--which comes in handy because it's hard to find a truly inertial frame in this universe.

    ...and the crackpot agenda comes out!
     

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    Quote Originally Posted by Layman View Post
    Back to this quote:

    'At this point I would like to reiterate the concept of "no preferred frame". Even though the two frame come to different conclusions as whether or not the clocks show the same time, each is equally entitled to his conclusion, and there is no absolute way to say who is "really" right.'

    While SR claims that there is no preferred frame, the theory actually basically posits that every observer is in his own motionless "preferred frame" and is, in essence, an ether to himself, right? Anything and everything is the universe which is moving relative to him is "moving," while he is "stationary," right?

    Put another way, in SR any given observer is strictly prohibited from assuming that he is the one moving. It MUST always be the other guy who is moving, right? The whole theory would fall apart if both A and B agreed that B was the one moving. That can't be allowed. They are REQUIRED to disagree about who is moving, correct?

    The "preferred frame" is always the one you happen to be in. There are an infinite number of these preferred frames, of course, when looked at collectively, but no observer in SR ever seems to acknowledge this. The "stationary" frame is always the one he is in, as far as he's concerned, and the possibility that the "other guy" is stationary and that he is the one moving is not just ignored, but flatly denied, best I can tell.
    Hardened crackpot, with an obvious agenda. This is not your first rodeo, is it?
     

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    "...and the crackpot agenda comes out!"

    For some strange reason, I was under the impression that I could find some reasonable, informed, rational discussion here. So far I see I was completely wrong. Questions and facts are apparently not welcome.
     

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    Quote Originally Posted by Layman View Post
    "...and the crackpot agenda comes out!"

    For some strange reason, I was under the impression that I could find some reasonable, informed, rational discussion here. So far I see I was completely wrong. Questions and facts are apparently not welcome.
    You are not asking questions. You are making statements. The crackpot kind.
     

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    "In both cases the disparity between the accumulated proper time is due to the fact that the clocks traverse different paths through spacetime. NOT due to one clock "ticking more slowly."

    Andrew, neither you nor your links have "explained" anything about clock rates. You seem to specialize in making sweeping assertions about distinctions without differences. There is a difference between explaining, mechanically, what causes a physical clock to run "slower" or "faster" and pontificating about what you think are theoretical explanations about why a clock slows down.

    If two initially synchronized clocks later disagree, then there is a physical (not mathematical) explanation for that fact. One clock has counted fewer ticks (oscillations, or whatever) than the other. Or is it your theory that a "path" just magically reaches inside the clock and moves the hands to suit it?
     

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    Quote Originally Posted by Layman View Post
    "In both cases the disparity between the accumulated proper time is due to the fact that the clocks traverse different paths through spacetime. NOT due to one clock "ticking more slowly."

    Andrew, neither you nor your links have "explained" anything about clock rates.
    This is beacuse it has nothing to do with clock rates. This has been explained to you countless times.


    If two initially synchronized clocks later disagree, then there is a physical (not mathematical) explanation for that fact.
    The physical explanation is that proper time accumulation is a function of path thru spacetime. This has been explained to you countless times.

    I have a question for you: how does you inability to learn SR lead you to the conclusion that SR is wrong?
     

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    Sorry, Andrew, you have "explained" nothing. You simply make rank assertions, which are irrelevant to the issue in question, without exhibiting even a modicum of theoretical understanding. You sound more like a parrot than a thinking physicist. Your agenda seems to insist upon the acceptance of non sequiturs as indisputable "explanations."

    You and I are obviously going nowhere. I am still hoping that their are participants in this forum who can exhibit some theoretical understanding (as opposed rote recitation) of the issues. Maybe one will come along eventually. Maybe not. We'll see, I guess.
     

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    Quote Originally Posted by Layman View Post

    You and I are obviously going nowhere.
    I have a question for you: how does you inability to learn SR lead you to the conclusion that SR is wrong?

    You, being a crackpot with an agenda, have been going nowhere. Go troll elsewhere.
     

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    According to SR, an old-fashioned wristwatch with hands on the dial (or any other clock) will slow down at increased speeds. Inside that watch are physical components (springs, gears, etc.). It is those component which ultimately produce the positions of the hands on the clock. It is NOT a "path through spacetime" which controls the hand on the clock, sorry.

    Frankly, I find it amazing that you are unable to understand this simple fact. It is not complicated and I think virtually any child could understand it. A car, for example, "runs" because of a complex interrelationship among various mechanical parts (wheels, engines, spark plugs, etc). It does not speed up or slow down by magic. When you press down on the accelerator there is a MECHANICAL explanation for why it begins to move. It is not a product of abstract "magic," gleaned from some theory. Without the physical parts, the theory is useless.
     

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    Quote Originally Posted by Layman View Post
    According to SR, an old-fashioned wristwatch with hands on the dial (or any other clock) will slow down at increased speeds.
    SR doesn't claim such a crankery. You do. You need to stop attributing your crankeries to SR.
     

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    Whatever you may think SR postulates, the simple, widely observed empirical FACT is that clocks DO slow down with increased speed. The GPS demonstrates this, for example, whether you like or accept the observed facts or not.
     

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    Quote Originally Posted by Layman View Post
    Whatever you may think SR postulates, the simple, widely observed empirical FACT is that clocks DO slow down with increased speed. The GPS demonstrates this, for example, whether you like or accept the observed facts or not.
    SR does not apply to explaining GPS. You need GR for that. Repeating the same crankeries doesn't make them true. Please go troll on another forum, this one is not for you.
     

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    You say: "SR does not apply to explaining GPS. You need GR for that. Repeating the same crankeries doesn't make them true. Please go troll on another forum, this one is not for you."

    Once again you display your lack of even an elementary understanding of the theoretical underpinnings of these physical theories. GR predicts the time distortions arising from proximity to the dominant gravitational field. SR (well, more accurately, the Lorentz transforms) predicts the distortions caused by the increased speed of the orbiting satellites. BOTH are needed to fully explain the overall clock distortions.

    Since we are talking about SR here, I didn't get into the irrelevant GR factors involved.

    You are completely mistaken when you say ""SR does not apply to explaining GPS," as you intend it. But in a way, you are right. SR, as a theory, does NOT adequately predict or explain the clock distortions resulting from speed. But the LT, along with the appropriate theory of relative motion (involving absolute simultaneity), do explain it and such considerations are absolutely crucial to designing a working GPS.
     

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    Quote Originally Posted by Layman View Post
    You say: "SR does not apply to explaining GPS. You need GR for that. Repeating the same crankeries doesn't make them true. Please go troll on another forum, this one is not for you."

    Once again you display your lack of even an elementary understanding of the theoretical underpinnings of these physical theories. GR predicts the time distortions arising from proximity to the dominant gravitational field. SR (well, more accurately, the Lorentz transforms) predicts the distortions caused by the increased speed of the orbiting satellites. BOTH are needed to fully explain the overall clock distortions.
    Can't fix ignorant crackpot.

    Since we are talking about SR here, I didn't get into the irrelevant GR factors involved.
    Can't fix ignorant crackpot.

    SR, as a theory, does NOT adequately predict or explain the clock distortions resulting from speed.
    Can't fix ignorant crackpot.

    But the LT, along with the appropriate theory of relative motion (involving absolute simultaneity), do explain it and such considerations are absolutely crucial to designing a working GPS.
    Can't fix ignorant crackpot.
     

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    Claims have been made in this thread which I believe are inaccurate. Einstein made it clear, from the inception, that acceleration, per se, has NO effect on time dilation (it is ONLY the speed). Accelerating will also serve to increase one's speed, of course, but that has no independent effect on time dilation. This has been proven in the lab many times. The so-called "clock hypothesis," is so fundamental to understanding SR that some view it as a "third axiom," and call it the "clock postulate."

    See, for example:

    https://en.wikipedia.org/wiki/Time_d...ock_hypothesis.

    A more elaborate explanation can be found at the John Baez website (link below), which states, in part, that:

    "It's often said that special relativity is based on two postulates: that all inertial frames are of equal validity, and that light travels at the same speed in all inertial frames. But in real world scenarios, objects almost never travel at constant velocity, and so we might never find an inertial frame in which such an object is at rest. To allow us to make predictions about how accelerating objects behave, we need to introduce a third postulate.

    This is often called the "clock postulate", but it applies to much more than just clocks, and in fact it underpins much of advanced relativity, both special and general, as well as the notion of covariance (that is, writing the equations of physics in a observer-independent way)....


    So the clock postulate says that the rate of an accelerated clock doesn't depend on its acceleration."

    Does a clock's acceleration affect its timing rate?
     

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    "Can't fix ignorant crackpot."

    Wow, Andrew! A very powerful, highly articulate, persuasively-reasoned scholarly argument you have presented there, sho nuff.

    You are the one who should "take a course," it seems. You have made a number of flatly incorrect claims about SR as a theory, I'm afraid. Given your all-pervasive opinionated bigotry, without any substantive content at all, our "discussion" will obviously go nowhere beyond your naked assertions. Sorry, but you are clearly not the polished theoretical physicist that you fancy yourself to be.
     

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    Quote Originally Posted by Layman View Post
    "Can't fix ignorant crackpot."

    Wow, Andrew! A very powerful, highly articulate, persuasively-reasoned scholarly argument you have presented there, sho nuff.

    You are the one who should "take a course," it seems. You have made a number of flatly incorrect claims about SR as a theory, I'm afraid. Given your all-pervasive opinionated bigotry, without any substantive content at all, our "discussion" will obviously go nowhere beyond your naked assertions. Sorry, but you are clearly not the polished theoretical physicist that you fancy yourself to be.
    Keep on trolling, crank.
     

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    Quote Originally Posted by Layman View Post


    So the clock postulate says that the rate of an accelerated clock doesn't depend on its acceleration."
    ...and, as already explained to you countless times, the clock rate has NOTHING to do with the twins paradox.
     

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    Layman, basically, accumulating less proper time does not actually mean ticking "slower". All clocks always tick at 1 second per second, as measured by an observer at rest in relation to the clock, and a second is always equal to 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom, as measured by an observer at rest in relation to the caesium atom.

    So, when, in layman's terms, it is said that a clock ticks "slower" due to relative speed, that is technically incorrect. So anyone basing any ideas on the notion of clocks actually ticking slower will be basing those ideas on a misconception.

    All clocks tick at the same speed, but two clocks can be taken along different paths through space-time, between two events. If those events are a comparison of the readings on the clocks whilst they are stationary in relation to each other, the clocks can show different elapsed proper times between those events, due to the different paths through space-time they took between those events.

    Now then, if we ignore all the discussion that has gone on above, what is the problem you are having with Special Relativity?
     

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    Hi, Speedfreak.

    1. You say: "All clocks always tick at 1 second per second, as measured by an observer at rest in relation to the clock...."

    That (as measured by....) is an EXTREMELY important qualification which Andrew failed to offer. Relative to EACH OTHER one, and ONLY one, clock does in fact "slow down." This has been confirmed by the GPS and many other empirical phenomena. It is the underlying premise of the explanation of the "twin paradox." Despite glib claims to the contrary, each clock does not actually and physically slow down, so that each ends up being slower than the other. Notwithstanding SR's philosophical claims, the rate change is NOT "reciprocal" in the external world (reality). Nor could it be since it is logically impossible for each of two clocks to be slower than the other.

    2. Put another way, all clocks do NOT "tick at the same speed" as you claim. That is exactly why the GPS clocks carried on satellites must be re-calibrated, in advance, so that they are programmed to take fewer ticks (oscillations) on those clocks to equal "one second." That is the only way to achieve useful clock synchronization.

    Do you disagree with this?
     

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    Quote Originally Posted by Layman View Post
    Hi, Speedfreak.

    1. You say: "All clocks always tick at 1 second per second, as measured by an observer at rest in relation to the clock...."

    That (as measured by....) is an EXTREMELY important qualification which Andrew failed to offer.
    Err, this is what PROPER TIME means. You keep exposing your crass ignorance.


    Relative to EACH OTHER one, and ONLY one, clock does in fact "slow down."
    Nope. Repeating the same nonsense doesn't make it true.



    It is the underlying premise of the explanation of the "twin paradox."

    Nope. Repeating the same nonsense doesn't make it true.


    Despite glib claims to the contrary, each clock does not actually and physical slow down, so that each ends up being slower than the other. Notwithstanding SR's philosophical claims, the rate change is NOT "reciprocal" in the external world (reality). Nor could it be since it is logically impossible for each of two clocks to be slower than the other.
    You suffer from the same affliction as Herbert Dingle. It is a quite common affliction amongst antirelativists.


    2. Put another way, all clocks do NOT "tick at the same speed" as you claim.

    Nope. Repeating the same nonsense doesn't make it true.



    That is exactly why the GPS clocks carried on satellites must be re-calibrated, in advance, so that it is programmed takes fewer ticks (oscillations) on those clocks to equal "one minute." That is the only way to achieve useful clock synchronation.
    This is not the reason. Keep up the trolling, it is quite entertaining.
     

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    Wrong again, Andrew. Here's how they do it.

    They can predict that a clock on earth will oscillate less frequently when it is travelling at speed X.

    For illustrative purposes, let's say an atomic clock will oscillate 10 million times per second on earth. But it is also known that, at an increased speed there will be fewer periodic oscillations--say 9 million, instead of 10 million.

    So they calibrate the clock so that, while it is orbiting at high speeds, it will say that 9 million oscillations equal "one second." Due to that essential re-calibration, the satellite clocks are then synchronized with earth clocks (actually with the "standard" clock which is located at the ECI).

    Are you aware of this? Apparently not.
     

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    Question for the forum admins:

    Why is my thread now in the "trash can?" Who put it there, and why?

    Is it an attempt to insure that posters with a better understanding of SR than Andrew shows will not see it and discuss the issues, that it?
     

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    Andrew said: "Err, this is what PROPER TIME means."

    OK, and the travelling twin will accumulate less net proper time elapsed than the earth clock. This is just another way of saying and acknowledging that clocks travelling at different speed do NOT "tick at the same rate."

    This is extremely elementary and obvious, why deny it?
     

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    I put the thread here.

    Okay, I'm going to be a little bit charitable here, and see if there is just a misunderstanding, or whether you are trying to push a fringe theory.

    So, just get to the point, Layman. I already asked you once - what exactly is the problem you are having with Special Relativity?

    Is it simply that time-dilation is symmetrical between inertial observers in relative motion? That statement is actually correct, and if you disagree with it I would ask you to come up with an experiment, either physical or just a thought experiment, involving purely inertial observers in relative motion (which is the only case where the time-dilation is symmetrical), that can disprove it.
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    Quote Originally Posted by Layman View Post
    Andrew said: "Err, this is what PROPER TIME means."

    OK, and the travelling twin will accumulate less net proper time elapsed than the earth clock. This is just another way of saying and acknowledging that clocks travelling at different speed do NOT "tick at the same rate."
    No, it doesn't. You are too dense to see the obvious: the two clocks accumulate different NUMBER of ticks. I pointed you to the very easy explanation in wiki.

    This is extremely elementary and obvious, why deny it?
    Your fixation against SR blinds you.
     

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    Andrew, I can "explain" to you "countless times" that there are 3 million pink rats living at the center of the planet Jupiter.

    But that is not an "explanation" at all. It is merely a hypothetical assertion presented without any evidence whatsoever.

    Your "space time paths" explain NOTHING about the periodic oscillations of physical clocks, no matter how many times you emphatically re-assert it, sorry.
     

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    Quote Originally Posted by Layman View Post
    Wrong again, Andrew. Here's how they do it.

    They can predict that a clock on earth will oscillate less frequently when it is travelling at speed X.
    Keep making up stuff, it is quite entertaining. The physicists USING GR (nothing to do with SR) have predicted that the satellite clocks will ACCUMULATE a different total elapsed proper time. Since the satellites send time-stamped messages to the land based GPS devices, the only way of making sure that the clocks "up there" are synchronized with the clocks "down here" is to adjust the frequency of the oscillators in order to make the total elapsed proper times the SAME. I could recommend a very good reading on GPS but I know that it would be wasted on you.


    For illustrative purposes, let's say an atomic clock will oscillate 10 million times per second on earth. But it is also known that, at an increased speed there will be fewer periodic oscillations--say 9 million, instead of 10 million.
    Nope, all atomic clocks using the same substance (be it rubidium or cesium) tick at the SAME rate. Keep making stuff up.


    So they calibrate the clock so that, while it is orbiting at high speeds, it will say that 9 million oscillations equal "one second." Due to that essential re-calibration, the satellite clocks are then synchronized with earth clocks (actually with the "standard" clock which is located at the ECI).

    Are you aware of this? Apparently not.
    You made everyone reading your posts painfully aware of your crass ignorance.
     

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    Quote Originally Posted by Layman View Post
    Andrew said: "Err, this is what PROPER TIME means."

    OK, and the travelling twin will accumulate less net proper time elapsed than the earth clock. This is just another way of saying and acknowledging that clocks travelling at different speed do NOT "tick at the same rate."

    This is extremely elementary and obvious, why deny it?
    Stop arguing about the definition of proper time.
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    Quote Originally Posted by Layman View Post
    Andrew, I can "explain" to you "countless times" that there are 3 million pink rats living at the center of the planet Jupiter.

    But that is not an "explanation" at all. It is merely a hypothetical assertion presented without any evidence whatsoever.

    Your "space time paths" explain NOTHING about the periodic oscillations of physical clocks, no matter how many times you emphatically re-assert it, sorry.
    Can bring the horse to the water but.....
     

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    Speedfreak said: ...I'm going to be a little bit charitable here...Is it simply that time-dilation is symmetrical between inertial observers in relative motion? That statement is actually correct..."

    ---------

    Preeminent theoretical physicists from Einstein to Feyman to Baez (or anyone else you can name) all readily concede that the claim that each clock LITERALLY runs slower than the other is a logical impossibility and therefore an absurd proposition.

    SR, or any other theory, can advance mathematically (actually philosophically) derived tenets to use in making accurate predictions. But that doesn't mean those tenets comport with "reality." Ptolemic (geocentric) astronomy is a case in point.

    I have no complaint about SR per se, as far as it goes (which really isn't very far given it's inherent "special" limitations). The problem that I have is with people claiming that SR corresponds to actual physical reality. It doesn't, even though it can work out mathematically in certain circumstances. Physics and math are NOT the same disciplines, contrary to what many practicing physicists seem to think.

    Chances are that you won't even understand the distinction I am making, but that's the "heart of it."
     

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    As Harvard professor of physics David Morin has noted, it would be a "disaster" for SR if observers travelling at different speeds did NOT deny and dispute the accuracy of the other's claims about time and length.

    If I am trying to use SR to make predictions while riding my motorcycle, SR MANDATES that I treat myself as "stationary" and insist that houses, stop signs, and anything else attached to the earth are what's moving. If I ever adopt the viewpoint that I am the one moving, not the houses, then all bets are off. The speed of light is no longer constant, etc.

    The only reason that the space traveller in the twin paradox (erroneously) concludes that earth clocks are "running slower" than his, is that he claims that HE is "at rest," despite knowing better. He did not remain motionless while the earth suddenly began to recede from him and distant stars began to approach him at blastoff.

    The time dilation is NOT reciprocal. The space twin will be younger and the earth twin older, not both. His claim that earth clocks were the ones moving was obviously mistaken. The proof is in the pudding--he ends up younger, not older, than his earth-bound twin.
     

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    SR is confirmed in particle accelerators (where the effects of gravity are negligible) daily. It is also confirmed by the time-dilation in the decay times (or length contraction of the atmosphere) of muons hitting our atmosphere. So SR does correspond with physical reality.
     

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    Quote Originally Posted by Layman View Post
    The time dilation is NOT reciprocal.
    It is between inertial observers in relative motion. I ask again for you to find a way to refute that.

    Quote Originally Posted by Layman View Post
    The space twin will be younger and the earth twin older, not both.
    Of course, because only one of them was inertial. Only one of them remained in the same inertial frame of reference throughout.

    Quote Originally Posted by Layman View Post
    His claim that earth clocks were the ones moving was obviously mistaken. The proof is in the pudding--he ends up younger, not older, than his earth-bound twin.
    Of course. Nobody disputes that.
     

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    A and B both acknowledge that there is relative motion between them. However, in SR:

    1. A must claim that he is at rest while B is the one moving (and therefore has a slower clock); and

    2. B must claim that he is at rest while A is the one moving.

    As a matter of simple logic they cannot BOTH be correct. If they were both "at rest," then there would be no relative motion between them. They could both be wrong, but both cannot possibly be right about their claims. At least one is mistaken.
     

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    Speed freak said: "SR is confirmed in particle accelerators (where the effects of gravity are negligible) daily. It is also confirmed by the time-dilation in the decay times (or length contraction of the atmosphere) of muons hitting our atmosphere. So SR does correspond with physical reality."

    This is a common misconception. What has actually been confirmed is that the Lorentz transformations make accurate predictions. Or alternately, other, equally plausible, theories of relative motion which incorporate the LT are ALSO "confirmed" by each and every experiment which "confirms" SR.

    The equivalency of theories positing absolute simultaneity with SR had been known since Einstein's time, and was subjected to rigorous testing many decades ago by Sexl, Mansouri, and others. Are you not aware of this?
     

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    Quote Originally Posted by Layman View Post
    A and B both acknowledge that there is relative motion between them. However, in SR:

    1. A must claim that he is at rest while B is the one moving (and therefore has a slower clock); and

    2. B must claim that he is at rest while A is the one moving.

    As a matter of simple logic they cannot BOTH be correct. If they were both "at rest," then there would be no relative motion between them. They could both be wrong, but both cannot possibly be right about their claims. At least one is mistaken.
    The whole point of the twins paradox is that it is only a paradox (i.e. each thinks the others clock is "slowed down", which is a paradox) if you fail to take into account that only one twin changed their frame of reference, whilst the other remained in the same frame of reference.

    Once you take into account all the changes in frame of reference, the paradox disappears.

    The only scenario where the time-dilation is symmetrical and reciprocal is when both twins remain in inertial motion throughout, just as Einstein claimed. Prove otherwise, using an example where there is only inertial motion between them, or stop talking.
     

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    Speedfreak, thank you for your concessions. However you also say: "Of course, because only one of them was inertial. Only one of them remained in the same inertial frame of reference throughout." The word "because" is inappropriate here.

    As you surely must know, the "twin paradox" can be formulated as a "three brothers" format where all parties "remain in the same inertial frame of reference thoughout." The "reference frame" is NOT what causes clocks to tick more slowly at increased speeds, nor is it acceleration (as I have posted, with citations, in another thread).

    But that aside, you are conceding, I take it, that even while the travelling twin is moving at a uniform rate of speed, he assumes that the earth clocks are running slower than his (when they are not), right? Time dilation is simply NOT reciprocal in practice. It is a function of speed, not "paths through spacetime."

    All speed in of course itself relative, but the space twin is "moving faster" than his earth twin (even though both are moving and neither is technically "at rest."
     

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    Quote Originally Posted by Layman View Post
    Speed freak said: "SR is confirmed in particle accelerators (where the effects of gravity are negligible) daily. It is also confirmed by the time-dilation in the decay times (or length contraction of the atmosphere) of muons hitting our atmosphere. So SR does correspond with physical reality."

    This is a common misconception. What has actually been confirmed is that the Lorentz transformations make accurate predictions. Or alternately, other, equally plausible, theories of relative motion which incorporate the LT are ALSO "confirmed" by each and every experiment which "confirms" SR.

    The equivalency of theories positing absolute simultaneity with SR had been known since Einstein's time, and was subjected to rigorous testing many decades ago by Sexl, Mansouri, and others. Are you not aware of this?
    Of course, but then again, Ockham's razor comes into play. We do not invoke ether theories to explain results where no ether is required.
     

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    Quote Originally Posted by Layman View Post
    Speedfreak said: ...I'm going to be a little bit charitable here...Is it simply that time-dilation is symmetrical between inertial observers in relative motion? That statement is actually correct..."

    ---------

    Preeminent theoretical physicists from Einstein to Feyman to Baez (or anyone else you can name) all readily concede that the claim that each clock LITERALLY runs slower than the other is a logical impossibility and therefore an absurd proposition.
    You suffer from the same affliction as Herbert Dingle.


    SR, or any other theory, can advance mathematically (actually philosophically) derived tenets to use in making accurate predictions. But that doesn't mean those tenets comport with "reality." Ptolemic (geocentric) astronomy is a case in point.
    Anti-SR is yet another serious, incurable, affliction.


    I have no complaint about SR per se, as far as it goes (which really isn't very far given it's inherent "special" limitations). The problem that I have is with people claiming that SR corresponds to actual physical reality.
    Tough. SR DOES correspond to physical reality. You need to seek help. The medical kind.



    It doesn't, even though it can work out mathematically in certain circumstances. Physics and math are NOT the same disciplines, contrary to what many practicing physicists seem to think.
    Please seek help. Soon.
     

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    Speedfreak said: "The only scenario where the time-dilation is symmetrical and reciprocal is when both twins remain in inertial motion throughout, just as Einstein claimed. Prove otherwise, using an example where there is only inertial motion between them, or stop talking."

    No empirical proof is even required, as the putative "reciprocity" is logically impossible. That said, the clocks on the GPS satellites "see" (i.e., make the assumption) that their clock is the one running slower because they are the ones moving at a higher (uniform) speed. They "see" the ECI clock as running FASTER than their own, not slower.

    The GPS is a marvel of modern engineering. What more "proof" do you want?
     

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    Quote Originally Posted by Layman View Post
    Speed freak said: "SR is confirmed in particle accelerators (where the effects of gravity are negligible) daily. It is also confirmed by the time-dilation in the decay times (or length contraction of the atmosphere) of muons hitting our atmosphere. So SR does correspond with physical reality."

    This is a common misconception. What has actually been confirmed is that the Lorentz transformations make accurate predictions. Or alternately, other, equally plausible, theories of relative motion which incorporate the LT are ALSO "confirmed" by each and every experiment which "confirms" SR.

    The equivalency of theories positing absolute simultaneity with SR had been known since Einstein's time, and was subjected to rigorous testing many decades ago by Sexl, Mansouri, and others. Are you not aware of this?
    Err , the Mansouri-Sexl theory is a test theory of .....SR! Keep digging yourself deeper.
     

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    Quote Originally Posted by Layman View Post
    Speedfreak, thank you for your concessions. However you also say: "Of course, because only one of them was inertial. Only one of them remained in the same inertial frame of reference throughout." The word "because" is inappropriate here.

    As you surely must know, the "twin paradox" can be formulated as a "three brothers" format where all parties "remain in the same inertial frame of reference thoughout." The "reference frame" is NOT what causes clocks to tick more slowly at increased speeds, nor is it acceleration (as I have posted, with citations, in another thread).
    But the clock reading are passed between frames with the three brothers, so there is where the change in frame of reference occurs.

    Quote Originally Posted by Layman View Post
    But that aside, you are conceding, I take it, that even while the travelling twin is moving at a uniform rate of speed, he assumes that the earth clocks are running slower than his (when they are not), right? Time dilation is simply NOT reciprocal in practice. It is a function of speed, not "paths through spacetime."
    No, it is a function of RELATIVE speed. And I guess he knows he changed his frame of reference when he moved from being on Earth to moving at a uniform rate of speed with respect to Earth. And I assert here that, no, acceleration does not cause time-dilation, I am well aware of the clock postulate. But a change in frame of reference IS required to break the symmetry of time-dilation.

    Unless, that is you change the three brothers into the four brothers, or five brothers, with clock readings passing back and forth. Try it. See where it gets you.
     

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    Quote Originally Posted by Layman View Post
    Speedfreak said: "The only scenario where the time-dilation is symmetrical and reciprocal is when both twins remain in inertial motion throughout, just as Einstein claimed. Prove otherwise, using an example where there is only inertial motion between them, or stop talking."

    No empirical proof is even required, as the putative "reciprocity" is logically impossible.
    Did you read the article on H. Dingle? He died insane.


    That said, the clocks on the GPS satellites "see" (i.e., make the assumption) that their clock is the one running slower because they are the ones moving at a higher (uniform) speed. They "see" the ECI clock as running FASTER than their own, not slower.
    You got this backwards. Keep posting, you are exposing more and more of your misunderstandings.

    The GPS is a marvel of modern engineering. What more "proof" do you want?
    So, what causes your beef with relativity? Come, out with it.
     

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    Speedfreak said: "Of course, but then again, Ockham's razor comes into play. We do not invoke ether theories to explain results where no ether is required."

    Just so you know, an "ether" is NOT a necessary requirement for a viable theory of relative motion employing absolute simultaneity.
     

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    Speedfreak said: "The whole point of the twins paradox is that it is only a paradox (i.e. each thinks the others clock is "slowed down", which is a paradox)."

    ------


    I disagree. That is not the "paradox" at all. People make mistaken assumptions every day and that does not create a "paradox." The "paradox" arises only because some naive theoreticians claim that there are no mistaken assumptions involved, and that, by God, each clock "really does" run slower than the other.

    That, my friend, is truly a "paradox."
     

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    Quote Originally Posted by Layman View Post
    .

    That, my friend, is truly a "paradox."
    ...and that insanity, my friend, lands your threads in....Trash.

    To explain away your madness:
    -in the frame of clock A , clock B is running slower than clock A
    -in the frame of clock B , clock A is running slower than clock B

    See how simple that is?
     

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    No, Layman, you are wrong about that, you really have it ass backwards.

    The paradox is symmetrical time dilation, where each thinks the others clock is slowed down. That is the paradox referred to, historically.

    You are making up your own, straw-man paradox and arguing against it.

    In order for there to be a paradox, you need two paradoxical measurements made in the same place. In order for that to happen, you have to bring the twins together, but the act of doing so breaks the symmetry which causes the paradox in the first place.

    This is how it is. And this forum is not the place for people pushing their own distorted view of things, hence why your thread is in the trash.

    Here, I will leave you with this:

    Alice and Bob pass each other in space, synchronising their clocks at closest approach. They then recede from each other.

    Later on..

    Carl passes Bob, heading back towards Alice and synchronises his clock with Bobs clock.

    Doug passes Alice, heading back towards Bob and synchronises his clock with Alices clock.

    Carl eventually catches up with Alice, and Alice sees the clock reading taken from Bob.

    Doug eventually catches up with Bob, and Bob sees the clock reading taken from Alice.

    Bob thinks Alice's clock has lost time.

    Alice thinks Bob's clock has lost time.

    WHO IS CORRECT?
     

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    "To explain away your madness:
    -in the frame of clock A , clock B is running slower than clock A
    -in the frame of clock B , clock A is running slower than clock B

    See how simple that is?"

    --------

    As usual, you totally miss the point. That's not the issue. Let's say that in my mind, I'm "smarter" than you and that in your mind, you're smarter than me. That is all purely subjective and, in itself, proves nothing.

    The point is that we cannot BOTH be right. At least one of us is wrong.

    Time dilation is NOT reciprocal as as an objective (as opposed to subjective) matter.
     

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    speedfreak asked: "WHO IS CORRECT?'

    That may never be known. But what is known is that they are not BOTH correct.
     

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    Quote Originally Posted by Layman View Post
    But what is known is that they are not BOTH correct.
    Actually, that is not known. Unless you can think of way to confirm it experimentally, thereof of what we do not know we cannot speak.

    If you claim the three brothers scenario bolsters your case that acceleration is not required, then I can just as equally claim that the four brothers (or three brothers and one sister!) scenario bolsters my claim that the time-dilation is indeed symmetrical. You may not like it but there it is.

    We can make no assumptions, the only way we can test it is to break the symmetry, whereupon the paradox disappears. This is because there is no physical paradox.
     

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    Speedfreak: As more traditionally posed the "paradox" consisted of demanding to know how you could ever get an absolute answer out of a theory that was purportedly strictly "relative."

    You can't. As resolved, the "twin paradox" ends up effectively adopting a "preferred" or privileged frame, i.e., the earth's frame. SR purports to claim that there simply are no preferred frames and that the use of a preferred frame is forbidden. But SR does use, and has to use, a preferred frame to get any kind of meaningful prediction. Likewise, astrophysicists routinely use the CMB as a preferred frame to make astronomical calculations, and they have been doing so for decades.
     

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    Quote Originally Posted by Layman View Post
    "To explain away your madness:
    -in the frame of clock A , clock B is running slower than clock A
    -in the frame of clock B , clock A is running slower than clock B

    See how simple that is?"

    --------

    As usual, you totally miss the point. That's not the issue. Let's say that in my mind, I'm "smarter" than you and that in your mind, you're smarter than me. That is all purely subjective and, in itself, proves nothing.
    You missed that the judgement is done in TWO DIFFERENT frames of reference. Go to school, take an intro class, you are lost. Totally.


    The point is that we cannot BOTH be right. At least one of us is wrong.
    I agree, you are wrong. Totally.


    Time dilation is NOT reciprocal as as an objective (as opposed to subjective) matter.
    Contrary to your madness, it is. Tough.
     

  80. #80  
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    Quote Originally Posted by Layman View Post
    Speedfreak: As more traditionally posed the "paradox" consisted of demanding to know how you could ever get an absolute answer out of a theory that was purportedly strictly "relative."

    You can't. As resolved, the "twin paradox" ends up effectively adopting a "preferred" or privileged frame, i.e., the earth's frame. SR purports to claim that there simply are no preferred frames and that the use of a preferred frame is forbidden. But SR does use, and has to use, a preferred frame to get any kind of meaningful prediction.
    False. The wiki page shows the problem solved from BOTH the frame of the Earth AND the frame of the rocket. You are outright lying.

    Likewise, astrophysicists routinely use the CMB as a preferred frame to make astronomical calculations, and they have been doing so for decades.
    CMB is not a frame. You are showing your crass ignorance. Again.
     

  81. #81  
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    Wrong, speedfreak. We do know that time dilation is not reciprocal.

    Watch the youtube video of Hafele and Keating repeating their classical experiment. At every stage of their trip they (accurately) predict that their moving airborne clock is running slower than a stationary clock at the ECI. They do so ONLY by assuming that time dilation is NOT reciprocal. They never try to claim that the ECI clock is the one running slow. If they did, their predictions would be completely wrong. They simply acknowledge that, as between them and the earth, they are "moving faster."

    When they emerge from the plane one, and only one, clock did, in fact, record less elapsed time--it was the moving clock, on the plane, not the earth clock and certainly not both clocks.
     

  82. #82  
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    Quote Originally Posted by Layman View Post
    Wrong, speedfreak. We do know that time dilation is not reciprocal.

    Watch the youtube video of Hafele and Keating repeating their classical experiment. At every stage of their trip they (accurately) predict that their moving airborne clock is running slower than a stationary clock at the ECI. They do so ONLY by assuming that time dilation is NOT reciprocal. They never try to claim that the ECI clock is the one running slow. If they did, their predictions would be completely wrong. They simply acknowledge that, as between them and the earth, they are "moving faster."

    When they emerge from the plane on clock did, if fact, record less elapsed time--it was the moving clock, not both clocks.
    In the HK experiment the conditions are not symmetrical. You keep exposing your crass ignorance. Keep up the entertainment.
     

  83. #83  
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    "In the HK experiment the conditions are not symmetrical. You keep exposing your crass ignorance. Keep up the entertainment."

    Of course they are not symmetrical. That goes without saying. Even though both are travelling at uniform speeds, one is moving faster than the other. Otherwise there would be no time difference.
     

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    Quote Originally Posted by Layman View Post
    "In the HK experiment the conditions are not symmetrical. You keep exposing your crass ignorance. Keep up the entertainment."

    Of course they are not symmetrical. That goes without saying. Even though both are travelling at uniform speeds, one is moving faster than the other. Otherwise there would be no time difference.
    You realize that you just admitted that time dilation is reciprocal? :-)
     

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    You and I are on earth, standing back to back, seeing entirely different things. You're looking north, and I'm looking south. We have different "frames of reference." Do our idiosyncratic circumstances in any way alter the earth, or what's on it?

    Of course not. Subjective frames of reference cannot alter objective reality. You don't seem to understand that simple truth, Andrew. You cannot differentiate subjective from objective "reality."
     

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    "You realize that you just admitted that time dilation is reciprocal? :-)"

    ------

    Heh, hardly. Quite the opposite. What do you think "reciprocal" means?
     

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    Quote Originally Posted by Layman View Post
    "You realize that you just admitted that time dilation is reciprocal? :-)"

    ------

    Heh, hardly. Quite the opposite. What do you think "reciprocal" means?
    You have no clue what you are doing.
     

  88. #88  
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    Quote Originally Posted by Layman View Post
    You and I are on earth, standing back to back, seeing entirely different things. You're looking north, and I'm looking south. We have different "frames of reference."
    Err, no. You have no clue what "frame of reference" means. Keep up the entertainment.
     

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    Just answer the question, eh, Andrew? What do you think "reciprocal" means?
     

  90. #90  
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    Quote Originally Posted by Layman View Post
    Just answer the question, eh, Andrew? What do you think "reciprocal" means?
    I explained that to you in post 69. Do not lose heart, keep trolling, keep exposing your crass ignorance, you are fodder for entertainment.
     

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    Post 69, eh? That says:

    "To explain away your madness:
    -in the frame of clock A , clock B is running slower than clock A
    -in the frame of clock B , clock A is running slower than clock B"

    --------

    There you use the word "is" in an ambiguous, incorrect manner.

    More accurate would be something like: "in the frame of clock A , A perceives that clock B is running slower than clock A

    But even that would be inaccurate, because A does not "perceive" any such thing with his physical senses.

    Accurate would be something like: " in the frame of clock A , A assumes (or postulates) that clock B is running slower than clock A"

    But again, both perceptions and assumptions can be wrong. If I've been eating LSD and "perceive" a horse to be a giraffe, that does NOT turn the horse into a giraffe.

    To say something is "assumed" to be reciprocal is quite different that saying that something IS reciprocal. The word "is" connotes actual existence, as an empirical matter, completely independent of any arbitrary assumptions.

    In any event, I certainly did not concede that time dilation is reciprocal. Not even close. I have no clue how you could even begin to think otherwiese.
     

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    Quote Originally Posted by Layman View Post
    Wrong, speedfreak. We do know that time dilation is not reciprocal.

    Watch the youtube video of Hafele and Keating repeating their classical experiment. At every stage of their trip they (accurately) predict that their moving airborne clock is running slower than a stationary clock at the ECI. They do so ONLY by assuming that time dilation is NOT reciprocal. They never try to claim that the ECI clock is the one running slow. If they did, their predictions would be completely wrong. They simply acknowledge that, as between them and the earth, they are "moving faster."

    When they emerge from the plane one, and only one, clock did, in fact, record less elapsed time--it was the moving clock, on the plane, not the earth clock and certainly not both clocks.
    BZZT! Don't watch youtube, actually study the literature.

    There were three sets of clock readings in the Hafele-Keating experiment, and two, yes two did in fact record less elapsed time than the third. Interestingly two, yes two clock readings also recorded MORE elapsed time than the third!

    There was the atomic clock at the US Naval Observatory, the clocks that were flown eastwards and the clocks that were flown westwards. The clocks flown eastwards lost time compared to the clock at the US Naval observatory, because they were moving faster than that clock on the ground. The clocks flown westwards GAINED time compared to the clock at the US Naval Observatory, because they were moving SLOWER than the clock on the ground! Go figure, who'd a thought it??

    The reason for this is that all three clocks were moving relative to an inertial frame at rest in relation to a frame around which the Earth rotates!

    The Eastwards flown clock moved fastest and lost time to the clock on the ground, the clock on the ground moved slower and lost time to the clock that flew west, and the clock flown westwards moved the slowest of all in relation to a frame at rest in relation to a frame around which the Earth rotates. The clock flown westwards gained time compared to the clock at the US Naval Observatory. The clock at the US Naval observatory gained time compared to the clock flown eastwards! Two clock readings lost time in relation to a third. Two clock readings gained time in relation to a third.

    And this does nothing to prove that time dilation between INERTIAL frames of reference is not symmetrical, because none of the frames involved were INERTIAL. The planes, constantly accelerating, aren't inertial. The clock on the ground, a rotating frame, is not inertial either.

    Just stop arguing, you don't know what you are doing.
    AndrewC likes this.
     

  93. #93  
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    Quote Originally Posted by Layman View Post
    Post 69, eh? That says:

    "To explain away your madness:
    -in the frame of clock A , clock B is running slower than clock A
    -in the frame of clock B , clock A is running slower than clock B"

    --------

    There you use the word "is" in an ambiguous, incorrect manner.
    Keep on trolling, crank.

    In any event, I certainly did not concede that time dilation is reciprocal.
    A crank doesn't concede. A hardened crank NEVER concedes. Keep it up!
     

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    speedfreak said: "The reason for this is that all three clocks were moving relative to an inertial frame at rest in relation to a frame around which the Earth rotates!"

    -------

    Exactly!

    That's the point I've been making. SR does not apply. If you want to say it doesn't apply because no earth frames are actually inertial (the planet is accelerating by constantly changing direction in it's orbit around the sun, after all), fine. SR really doesn't "apply" to much at all if that's the reasoning. SR is, essentially, worthless as a practical theory of relative motion in that event. Of course the clock postulate (I've posted on this elsewhere) says otherwise (regarding clock behavior, anyway), but, whatever.

    The point is that they were in fact able to accurately predict what the resulting readings of elapsed time would be on each of the 3 clocks, but NOT by using SR. They had to use a theory of relative motion which incorporates absolute simultaneity (a preferred frame of reference) to make accurate predictions. SR, as a theory, did not, and could not, accurately predict the clock's eventual readings.

    In the type of theory used by HK, there is NO reciprocity. All elapsed time differences are "directional," meaning that they go only one way and that they are not "reciprocal."

    I was aware of the HK data, so you're not telling me anything new. I do hope you have learned something "new" about putative "reciprocal time dilation" though. It doesn't exist.
     

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    SR basically says that time dilation is solely a function of the relative motion between any two objects. This has been disproven also.

    London, Berlin, Milan, New York, Los Angeles, etc. never move relative to each other. Yet they all differ in the amount of time elapsed because the are at different latitudes, as recent experiments (which rejected SR and used an absolute simultaneity theory of relative motion) have demonstrated.

    Furthermore it takes an electromagnetic wave (such as light) longer to go from New York to LA than from LA to New York. SR says the speed will be the same regardless of the motion of the emitter of the signal. Wrong. The HK data you cite also demonstrates this fact.

    I have a feeling that both you and Andrew would be extremely hard pressed to give a clear exposition about the difference between relative simultaneity (as posited by SR) and absolute simultaneity. That difference is of crucial importance to competing theories of relative motion, however.
     

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    Clock A runs slower than clock B, and, at the same time, clock B runs slower than clock A.

    This is a self-refuting logical contradiction. You, Speedfreak, are calling for experiments to prove it's false. Experiments DO prove it's false, but there is no need for them. Any theory incorporating a logical contradiction is discarded post haste. There is no reason to experimentally "test" such a theory.
     

  97. #97  
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    Quote Originally Posted by Layman View Post
    SR basically says that time dilation is solely a function of the relative motion between any two objects. This has been disproven also.
    Crank . Relentless. Enjoy your residing in Trash.


    I have a feeling that both you and Andrew would be extremely hard pressed to give a clear exposition about the difference between relative simultaneity (as posited by SR) and absolute simultaneity. That difference is of crucial importance to competing theories of relative motion, however.
    Not at all. But it is not worth wasting my breath on a hardened crank.
     

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    A brief excerpt from a wiki article summarizing the results of the Mansouri-Sexl experiments:

    "By giving the effects of time dilation and length contraction the exact relativistic value, this test theory is experimentally equivalent to special relativity, independent of the chosen synchronization. So Mansouri and Sexl spoke about the "remarkable result that a theory maintaining absolute simultaneity is equivalent to special relativity." They also noticed the similarity between this test theory and Lorentz ether theory of Hendrik Lorentz, Joseph Larmor and Henri Poincaré."

    https://en.wikipedia.org/wiki/Test_t...ial_relativity

    You can read the entire article if you want to achieve a better understanding of absolute versus relative simultaneity. Needless to say, it is even better to read the complete multi-series scientific papers published by these scientists.
     

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    Quote Originally Posted by Layman View Post
    A brief excerpt from a wiki article summarizing the results of the Mansouri-Sexl experiments:
    Mansouri and Sexl did not do any experiments.
     

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    "Mansouri and Sexl did not do any experiments."

    Well, that depends on what you want to call an "experiment," I guess. They analyzed a number or previously conducted experiments to see if the empirical observations made there would be confirmed by their model, which deviated from SR's premises. They were experimenting with models, you might say.

    However you say it, their alternative model was completely consistent with all known empirical data.
     

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