Is time universal? NO (and its proof)

Discussion in 'Physics & Math' started by Billy T, Aug 12, 2005.

  1. DaleSpam TANSTAAFL Registered Senior Member

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    I know the quote text is small, but you really should read more carefully. I derived time dilation too and the time dilation is insufficient to explain the light clock in both orientations.

    Perhaps you need an ocular supplement rather than a memory supplement.

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    -Dale
     
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  3. Pete It's not rocket surgery Moderator

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    Except the ruler can be in any frame?
     
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  5. MacM Registered Senior Member

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    I am less concerned about the failure of SRT than I am as to what a correct physics view predicts.

    False. The error you make is making assumptions. My scenario makes no assumptions. It simply does not ignore the dilated tick rate of the moving clock. The correct physics is to recognize frame dependant time and them to recognize that such time dilation prohibits length contraction based on actual physical data.

    That is I use no assumptions. I use the FACT of time dilation and the dilated accumulated trip time to show the failure of length contraction.

    Of course light invariance would create several intersting issues but none dictate SRT as a conclusion. It is ill considered and ill based on physics. The point you should get through your head is that I am not rejecting an invariant 'c' to show the failure of length contraction.

    I am showing that time dilation which is a result of relativity and an invariant 'c' results in frame dependant veloicty, not frame dependant length.

    I don't get your objection. Relativity survives but is merely ammended in this view. None of the amendments conflict with any known emperical data. It is only some of the unproven and undemonstrated assertions that are changed.
     
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  7. Pete It's not rocket surgery Moderator

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    This is an assumption:
    "Length is the same in all frames."

    This is not an assumption:
    "Maybe length is the same in all frames, maybe it isn't."

    SR starts from the second position.
     
  8. quadraphonics Bloodthirsty Barbarian Valued Senior Member

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    I'm not sure why you're asking me this... If one assumes, as you have done, that all of the differences in trip times are accounted for purely by time dilation, then indeed, one does not require additional effects such as length contraction. The point, however, is that such a theory runs into a bunch of problems. It makes velocity frame dependent, so there's no way for two moving observers to agree on what their relative velocity is, without invoking some kind of absolute reference frame. You need to use both time dilation and length contraction to account for the differences in trip times if you want a theory of relativity with frame invariant velocity.

    Err... huh?
     
  9. MacM Registered Senior Member

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    Correct and that is what emperical data supports.

    Name one.

    Ah, you are clever indeed. That is the very point of this presentaton. It shows that data actually supports an absolute concept vs the relative one.

    I really don't think nature (the universe) cares what you want. I think it does whatever it does and we should attempt to understand what it does without trying to twist it to fit our preferred view.

    I for one see little differance between having length frame dependant or velocity frame dependant. Both are concepts of relativity. The point is data supports the latter and precludes the former.

    It really is not a matter of preferance. What it comes down to is keeping physical enities intact, i.e. - length and time but let the calculated value vary, don't vary one of the standards.

    Variable time (dilated time) is a known standard, distance is a known standard. Velocity is a calculation of these standards.
     
  10. MacM Registered Senior Member

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    Wrong. It is physical fact mandated by the emperically demonstrated fact of time dilation.

    No it doesn't. It starts from the ludricrus arguement that two different (and I mean different) time periods are the same.
     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I have deleted the original of following. (I did not want it pushed down so far that MacM can pretend he did not see it. It is becoming obvious that MacM is for once speachless!) Eight pages back, MacM said:

    I replied:

    "The whole point of the thought experiment I set up is that it never invokes SR, never make reference to time dialation, never refers to contraction, never requires any calculation, never has any propagation delays, never has any "perception," never assumes the velocity of light is the same in all frames, etc.

    Unfortunately, you never consider/ discuss the experiment or the four assumptions it does make, which are:

    (1) Experiment assumes that the speed of light in any one frame is not dependent upon the direction in which the light is traveling.

    For example, the conclusions of the experiment (that simultaneous events in one frame are not simultaneous in another moving wrt to the first) still follows if the speed of light in the embankment frame is only 10^4m/s and in the frame of the train is 3x10^8m/s. But whatever the speed is in either frame, I did require that light going in the direction the train is going has the same speed as light going in the opposite direction in any one frame.

    (2) There is a very brief flash of light, which when it occurs is equally distant from both the front of train firecracker and the firecracker at the rear of the train.

    (This was assured by having the flash bulb mounted on the train at the mid point, but if you like it can be mounted on a pole in the ground and triggered by a small copper arm that sticks out from the mid point of the train and completes the electrical circuit, flashing the light. Point is that there is a flash of light that occures exactly midway between two photo sensors that trigger the co-located bombs.) I like the flash bulb mounted on the train so it stays always mid way, as if I mount the flash bulb on the ground post, then I would need to asssume that once photons leave their source, the motion of this post (and source), or lack thereof, has no effect on the photons (a very reasonable assumption, but why make it, if it can be avoided?)

    (3)The train moves during the time interval in which the light is traveling towards the two firecrackers.

    (4) I have very many ground mounted stop watches so that one is adjacent to each explosion and two on the train, one adjacent to each explosion. All four are stopped by the adjacent explosions, recording the time the explosions occurred. No propagation delays. No perception delays. (No one even looks at the times of the explosions recorded on these stopped watches for a least a week.)

    RESULTS: The two stopped train clocks show the explosions occurred at the same time but the ground clock that was next to the rear explosion recorded the time of it as BEFORE the time recorded by the ground clock next to the explosion at the front of the train. (Because, while light was traveling, the rear of train advanced towards the light and front of train tried to run away from the light coming to it.)

    Again: none of the things you do discuss is of any concern. There is no use of SRT, no calculation, no propagation delays, no..... Just a lot of ducking and weaving as you try to find some reason to avoid the obvious conclusion:

    Simultaneous events in one frame are not simultaneous in another.
     
  12. MacM Registered Senior Member

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    Don't hurt your arm patting your back. It isn't warranted. The thread is dying since it goes nowhere. The current threads by Pete and myself on the issue of length contraction is designed to resolve the arguement.

    Your thread is based on the assumptions that invariance of light is properly interpreted. That conclusion is not supported on actual investigation.

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  13. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    It appears MacM has run out of duck and weaves, so now he lies or can not read.

    I said:
    Experiment assumes that the speed of light in any one frame is not dependent upon the direction in which the light is traveling.

    For example, the conclusions of the experiment (that simultaneous events in one frame are not simultaneous in another moving wrt to the first) still follows if the speed of light in the embankment frame is only 10^4m/s and in the frame of the train is 3x10^8m/s. But whatever the speed is in either frame, I did require that light going in the direction the train is going has the same speed as light going in the opposite direction in any one frame.
     
  14. MacM Registered Senior Member

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    Those that can read and are not biased can see that this is not a resonse to my post. It is your typical method of simply making selfserving statments and ignoring your opponents responses.

    Can you or can not give evidence which disputes the concept that photons are energy (frame) dependant. Meaning photons in your train rest frame are not the same photons seen in the embankment rest frame.

    Which means the photons seen in the embankment frame have nothing to do with the explosions. The only photons that can detonate the explosives are the photons in the trains rest frame.

    What you get is simultaneous explosions in all frames. But only in the trains frames does it appear that light triggered the explosions. That wasn't so hard now was it.
     
  15. Pete It's not rocket surgery Moderator

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    Ah, the silent majority.
    No matter what the vocal opposition, one can always feel comforted by the notion that somehow, somewhere, someone hears and agrees even if they don't speak up in support.

    Magical photons that pass through anything not moving at the right speed?
    Like you said (in a different context, of course): "You have no basis to change such relationships."

    So in the embankment frame, the bombs apparently detonate by magic?

    I think Dr Dowdye would shudder to hear your mangled vision of his ideas, Mac.
     
  16. MacM Registered Senior Member

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    10,104
    Ahhh, magical photons that remain at the same velocity to any observer regardless of the observers velocity . :bugeye:

    Yep.

    Actually he rather likes my views and shuddrs at the assinine views of relativity.
     
  17. DaleSpam TANSTAAFL Registered Senior Member

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    Can you or can not give evidence which shows that your frame-dependent photon idea doesn't lead inevitably to relativity?

    So far your justification given for why frame dependent photons don't lead to relativity is "because frame-dependent photons don't need relativity". Since you haven't changed their motion and since the postulate of relativity is only based on the motion of light your photons still lead to relativity.

    -Dale
     
  18. MacM Registered Senior Member

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    Yes and No. I have made the point (if you missed it) that in my view relativity survives. However, it is not A.E.'s relativity. Reciprocity does not exist. Velocity becomes frame dependant and length invariant compared to reciprocity, velocity invariant and length frame dependant.

    What I said a while back is I think it would be most interesting to look at the universe and what we would expect emperical data to show under these conditions rather than argue which view is valid.

    It is entirely possible that some distinction might be noted which could differentiate these views from existing data. Keep in mind that at least at this juncture it seems that data supportrs my view better than SRT.

    It seems far less intrusive to physics to retain physical parameters and let the calculated value vary than it does to alter physical parameters. Time and distance are physical parameters, veloicty is a calculated value.
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Indeed, the energy and color of the photons is "frame dependent" (normally referred to as red and blue shift.) but this though experiment is concerned only with the transit time from source to the photo triggers of the firecrackers. I think by diverting attention to the irrelevant color, you have finally earned credit for duck and weave, 16. Congratulations.

    Correct. The photons that are absorbed in the photo trigger devices are not seen or in any way detectable by devices on the ground or people on the train etc. You can only detect any give photon once if it is absorbed in a detector, as I have been tacitly assuming. (I.e. the photo detectors are simple photocells, not very lightweight mirrors that can have their recoil upon reflecting a photon measured. (May be impossible in principle at any temperature above liquid helium because of shot noise effect, but I certainly do not want to give you an opening for "duck and weave 17" so let me now state that the photo detector triggers do absorb the photons incident upon them.)

    No it was easy as it is wrong, as usual. The four clocks adjacent to the two explosions are stopped by the explosions not by the photons that trigger the explosions.

    As the two clocks on the train remain the same distance from the origin point of the light flash, (the flash bulb also mounted on the side of the train mid way between two firecrackers and thier phot triggers) the two train clocks stop at the same time. ==> Simultaneous explosions.

    As the train moves in the embankment frame while the light* is traveling towards the photo detectors the train end approaches the oncoming light and the front of the train moves further away. Consequently according to ground clock's time (with my sole assumption that speed of light is independent of direction, even if of vastly different speed in every frame in violation of SRT.) the rear explosion precedes that at the front of train ==> not simultaneous.

    Do you think that clocks adjacent to the explosions and stopped by them do not record the time of the explosions? Do you not understand that the ground clock stopped by the rear explosion is closer to the origin of the light flash than the one at front which is adjacent to the front firecracker, which has been moving down the track while the light was racing to it? What is it you do not understand? Most see it is obvious that the rear explosion ground clock is stopped before the one stopped by the front explosions.
    _____________________________
    *Which admittedly will be absorbed only in train mounted photodectors (but they are sensitive to all colors of light - so duck and weave 17 is as irrelevant as all the 16 preceding ones.)
     
    Last edited by a moderator: Jan 30, 2006
  20. MacM Registered Senior Member

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    10,104
    What do you not understand about the explosions are only triggered by the photons in the trains rest frame and the observation of other photons at a different energy level and different time have no impact on the explosions.

    Nobody (but you) has discussed red shift or blue shift.

    Infact I'm glad you brought up the subject since we can now incorporate optical color filters on the explosion triggers.

    What the hell are you going to do now? Your photons in the train frame can and do set off the explosions but the red and blue shifted light in the embankment frame would be rejected. Hmmmm.

    Thanks.
     
  21. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    You asked me to "give evidence which disputes the concept that photons are energy (frame) dependant." As for photons, energy and color are linearly related I did mention color first, but only to make sure you knew that is what your "phonon are energy (frame) dependent," which you mentioned first, is all about, but lets not get into who said what first - you will not get credit for duck and weave 17 that way.

    Are you so confused that you think more energetic photons travel faster? If you are thinking this is true because "photons are particles" and it is true for non zero rest mass particles, then we need to start your physics education at a much lower level. Do you agree that photon energy is irrelevant in this thought experiment?
     
    Last edited by a moderator: Jan 30, 2006
  22. Physics Monkey Snow Monkey and Physicist Registered Senior Member

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    MacM, I usually just ignore you and your mindless ranting because its obvious you don't care much about reason and experiment. However, I do try to keep the facts straight for everyone else, and as usual you have misrepresented the facts. Regarding your color filters, what makes you think that the light won't pass through the filter in the embankment frame. In fact the light will pass through the filter in the embarkment frame if it passes through in the train frame. You have assumed incorrectly that a filter calibrated to pass a certain frequency of light will function independently of its motion. There are numerous exmaples available, but one which I find especially interesting is the laser cooling of atoms. In such experiments, it is neccessary to periodically readjust the frequency of the laser in order to maintain resonance with the atoms as they cool (slow down).
     
  23. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I am still confused by this phrase. How does one determine which frame a photon is "in"? How would I know if it is "in" the train's frame or "in" the embankment frame?

    Please, for example, describe for me, at least in principle, how one determines whose frame a photon falling on you at the beach was in before it was destroyed by skin absorption. Or at least tell me which frame - for example: The frame moving with the sea breeze? The sun’s frame? Frame of the Earth center? CoM of the solar system? Etc. or is this all just more nonsense that I should not try to understand?

    Are you saying that it is like your "absolute reference frame", existent, but impossible to determine? Something to be accepted on “faith”? To say this about photons is much worse than about absolute reference frames, as I know photons do exist, but do not understand them to have any characteristic other than frequency*, and velocity**. ( Plus spin one, and polarization direction also, if you want to speak of the way man has decided to classify them in mathematical systems he has created.)

    You seem to think they also have (or belong to) some particular frame. Please try to clarify this "photon's frame concept." thanks.
    _________________________________________
    * Varries with the frame it is observed in.
    **Varies with the material it is traveling thru, but not with the frame it is in.
     
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