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Has einsteins experient with time been proven, why hasn't it been applied or used

  1. Nov 8, 2009 #1
    The experiment showing that, time is relative, and how it changes with velocity and gravity. Einstein's twin experiment. One twin stays on earth while the other flies for 5 years at some velocity near the speed of light. let's say he travels at .8c. he then turns around and travels at .8c back to earth. when he gets back, he will find that he has aged 10 years, but is brother has aged significantly more. If they both had telescopes and could watch each other during this trip, then the twin on earth would see his twin moving in slow motion, while the one on the ship would see his bro moving really fast.
    Has there been very much more research done with this experiment? And, Has it actually been proven, most importantly, can it or will it ever be applied or used for much of anything? Do we have the capacity to do so?
    Last edited: Nov 8, 2009
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  3. Nov 8, 2009 #2


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    It's been used extensively. The Global Positioning System must correct for relativistic effects for example. Everything that has to do with high energy physics uses it, it's been tested extremely well.
  4. Nov 8, 2009 #3


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    There is no "the experiment" - there are many, many experiments plust practical applications* that have tested and do test both parts of relativity on a continuous basis.
    That's a thought experiment. It wasn't meant to be tested and can't be tested with current technology, nor does it need to be.

    *GPS is a practical application that utilizes Einstein's theories.
  5. Nov 8, 2009 #4


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    Pretty much every single test that confirms General Relativity is confirming the effect you describe. Everything is so cohesive in the theory that it would make no sense if certain parts turn out to be correct but others are not.

    As far as an actual experiment goes, it's a bit tricky to do here on the Earth. There were some experiments where one clock was kept on the ground and another flown in a plane for a while, and afterwards the two were compared. The time dilation effect here is however a mix of gravitational time dilation (the majority) and velocity dilation.
  6. Nov 8, 2009 #5
    I think I should pont out to the OP that the correction of GPS signals is necessary due to GR effects whereas the twin paradox comes from SR.
  7. Nov 9, 2009 #6


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    Actually, GPS satellites have their clocks corrected to account for both effects.
  8. Nov 9, 2009 #7
    Just a quick question with regard to the time dilation effect (if that's the correct term).

    I would still question how the entity known as time has actualy been affected, as opposed to the effects being on the mechanics of the timekeeping device.

    I'm not sure if it was explained correctly, but I was informed that the atomic clock measure the microwave output of electrons as they change. Therefore, is time the microwave output of changing electrons?

    It just appears that gravity, and whatother mitigating factors, may have a material effect on the microwave output of electrons as they change.

    If that is a correct description of how the atomic clock works (or a general description at least), then is time simply the the microwave output of electrons as they change, and not some all inclusive "fabric of reality"?

    Just to calirfy further, when we say that something changes or occurs over a certain length of time, do we really mean that something has occured or changed relative to the number of microwave emissions from changing electrons?
  9. Nov 9, 2009 #8

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    Since it affects all timekeeping devices, irrespective of their mechanism, how do you propose to tell the difference?
  10. Nov 9, 2009 #9


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    It is very easily demonstrated in any particle accelerator. Particles accelerated to relativistic velocities have a longer decay - they live longer - exactly matching the time dilation claimed.

    Atoms and subatomic particles are the smallest units in our universe, so, if dilation affects them, there's not much left to separate the 'mechanisms measuring time' from 'time itself' - if that is even a meaningful distinction.
  11. Nov 9, 2009 #10
    I agree with Mangaroosh - Mechanical explanations for the time dilation. I understand having different frames of reference will give different times as to when an event occurred. But the event itself happened at one moment/slice of time. I currently think of time (my own little theory at the moment - don't ask for mathematical explanations! I am not YET that smart!) as being like a field that acts less upon objects that are in motion. (I think of time as the highest-top tier dimension - the multiverse has one time dimension - a topic for another thread) "The faster you move the less time acts upon you". Is there anything out there that makes these ideas completely untrue? I see the principles of GR in everyday life (GPS and the like) but I am leaning toward GR being a amazing tool but also its geometric visualizations may really hinder discovering the true mechanism of gravity. I feel the same way about Quantum Physics but let me state these are my own ponderings' and should not be taken as an assault on what we know today. I need to understand everything before I can attempt anything like that! :tongue2:
  12. Nov 9, 2009 #11


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    Can you give a mechanical rationale for why subatomic particles with no internal parts (let alone moving parts) have their decay lifespans dilated exactly in accordance with SR?
  13. Nov 9, 2009 #12

    Vanadium 50

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    Noja888, please take a look at the PF Guidelines on "Overly Speculative Posts" before going too far down the path of describing your own theory.
  14. Nov 9, 2009 #13
    Do particles gain mass with velocity? I would reason this extra mass would take longer to decay than a particle with less mass. Is there a fundamental rule I am missing with "particles"? If we split an electron into its components - is that not its "internal parts" or am I confusing classical mechanics with the realm of quantum? Do the internal parts absolutely not exist until the electron is "smashed", breaking into them?
  15. Nov 9, 2009 #14


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    Yes. Just like everything else.

    This is nonsense.

    An electron does not have internal components. It is indivisible.

    Electrons are not smashed into smaller components.
  16. Nov 9, 2009 #15
    OK-sorry-electron was bad example - How bout a proton? - two up quarks and one down quark. Do the quarks only exist when they are quarks? - no wait... nevermind, then an atom would only be an atom.

    -My reasoning with the "Greater Velocity = More Mass = More energy" Kinetic effect on a particle. I do not understand why more energy does not take more time to decay a particle so I will have to learn more why this is nonsense (I believe you Dave - I just need to learn why). Is there a certain topic I should explore to understand why my idea is just silly? I think my understanding of time dilation has been warped by bad thought experiment samples while trying to visualize GR and SR. I read that the numbers found from the test of a stationary clock measured against a clock in a plane flown around the earth a few times had around a 4% difference from measured to predicted results - not bad - there is lots of extra variables in that experiment. Was the particle experiment closer from measured to predicted numbers? I would guess it would be extremely close. Or we could say relatively closer. (pun-intended) :wink:
  17. Nov 9, 2009 #16


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    You're looking at it backwards.

    Insstead of asking why your thinking is not right, ask why you have that thinking in the first place. Why would you think that "more energy leads to longer delay"? Is there some precedent that you're following? Some previoius experience where this was so that you're using as an example? You're trying to apply everyday "common sense" concepts to an area that is outside of our common experience.

    I think you're making the mistake of trying to map your current models of the macro world into new areas of the subatomic worlds and relativistic worlds.

    An example: The common man used to think that electrons orbited atoms kind of like planets orbit the sun. We now know that electrons are constrained by orbitals. There is no macroscopic counterpart to an electron orbital. The math describes how it works, and that's really as good as it gets.

    So, what I'm suggesting is that, at some point in examining high velocities, there is no "model" that will easily describe time dilation and particle decay. You form the postulate and work out the math and it maps back onto your observations.

    Common sense comes after you accept the non-intuitive truths of what is.
  18. Nov 9, 2009 #17


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    I once posted a well-received explanation of this here: https://www.physicsforums.com/showpost.php?p=1561105&postcount=3
  19. Nov 9, 2009 #18
    That still does not show that time is anything other than a measurement, as opposed to something that is measured, and while it matches the theory perfectly, it amounts to, as far as I can see, circular reasoning for the existence of time - where time is apparently being used to show that time exists.

    What it does show is that the conditions the particles endure in the accelerator, have an effect on the decaying process, it isn't time that has the effect. The effect itself is measured using a unit of measurement, which is given the name time. This thing that it is measured against is the microwave emissions of electrons as they change. So it would be more accurate to give the life of something as the number of microwave emissions.

    What are the microwave emissions of changing electrons measured against, if they themselves are what is used to measure time?

    Time is just like distance, it is a subjective measurement, the difference being that something is measured against itself, in a past state, which ceases to be a part of reality as soon as it changes. That is, the past state is no longer part of reality.

    To try and illustrate this, we can take the example of the earths rotation. Now, we can plot the superposition (have I got that term right?) of the earth as its orbit around the sun. we can do this with a high degree of accuracy.

    We can set a clock running now, and stop it in five minutes time, and we can draw a line between the two still frames of the earth, and take that to be a part of its orbit. Just as with cm, metres, etc. we can mark off that line in units that correspond to seconds or minutes. This is in effect the time line, it represents the amount of time that has passed between the past position of the earth and its current position. The problem however is that the line is completely imaginary, and arbitrary, it doesn't actually exist. In fact, neither does the past location of the earth. The earth only exists in one location along its plotted orbit. Any measurement of a past location is a measurement of something that is no longer real, or is no longer part of reality. The earth exists in one place and one place only.

    Therefore any measurement of the earths past position to its current one, is a measurement of non-reality (or something that is not real) with reality (something that is real). It's just like measuring the distance between two arbitrary points on the earth. While the distance itself can be measured, neither the points nor the line actually exist.

    I don't mean to trivialise the above example of the particle accelerator, but it might help to explain it in these terms. If I eat a healthy and balanced diet, then the chances are that I will live longer, than if I eat an unhealthy diet, all else being equal. This is due to the conditions I live my life under, as opposed to the outside force of time.
  20. Nov 9, 2009 #19


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    It isn't circular reasoning. You make predictions and the predictions either come true or they don't. When the predictions come true, the theory is affirmed, when they don't, the theory is falsified.

    In the case of our concept of time, multiple independent meathods of measuring time -that didn't even exist when Einstein formulated his theories - agree with the theory to an extrordinary level of precision. This implies only three possible conclusions.

    1. Our theory of what time is/how time works is correct.
    2. Multiple experiments measuring completely different physical processes have produced results that fit with relativity but actually are measuring an different effect.
    3. Through an extrordinary coincidence, multiple experiments have produced erroneous results that just so happen to match the theory.

    Possibility #2 is possible, but unlikely due to just how different the various experiments are from each other. Really, what this would imply is that Relativity is very close to correct but not quite correct - which would basically come down to hairsplitting.

    Possibility #3 is much too far fetched to be taken seriously. There are lots of different types of clocks and most have very well understood error mechanisms. Even mechanical clocks such as pendulum clocks - you can predict how they will behave in a differing gravitational field. And different clocks will have different error sources and error amounts. But the "clocks" used to test Relativity have no known errors that could account for the predictions of Relativity.

    ...There is also the issue of the lack of absolute speed making it impossible to pin down a "real" speed of a clock: a clock can simultaneously have an infinite number of possible physical speeds with respect to an infinite number of different reference frames and there can be an infinite number of different dilations between these frames. So you can't really say that speed affects clocks because clocks have only one "speed" that they care about: their own speed of zero with respect to themselves.

    That is an incorrect characterization. Time is not measured against itself any more than a meter stick is measured against itself. Physical lengths are measured with meter sticks: time is measured with clocks.
    You have a very odd and incorrect view of what it means for a position to exist. In any case, since you just argued that "past locations" don't exist, then to be internally consistent, you would need to discard the concept of distance.

    Any any case, that's all nonsense so it is best not to dwell on it. It seems you've made a decision here that you just plain don't want to accept what Relativity says. If you won't take experiments at face value, there may not be much left to discuss.
    Last edited: Nov 9, 2009
  21. Nov 9, 2009 #20
    Could there be a fourth posibility? That the physical effect of the environment impacts on the microwave emissions of electrons equally for all atoms, which in turn will affect all the time keeping devices in the exact same manner?

    There could of course be other explanations, but for now they are not really necessary.

    This isn't the case though, so restating it does not add any credence to the assertion. The thing is, we can trace the measurement of a metre back to an arbitrary choice:

    Now it has evolved from there, but you get the point. So when we talk about a metre, we are actually talking about the comparison against "a minute of arc along a meridian" of the Earths circumference. But that in itself is a completely arbitrary decision. Just like the measurement of a yard, which was equally taken from a completely arbitrary object. So any talk of yards is to compare something to whatever it was that was taken as the original measurement.
    So for example, if we talk about the earth's circumference in metres, it is somewhat circular in reasoing, because the distance of a metre was derived from the circumference of the earth.

    Equally, a clock doesn't actually measure time. Older clocks were used to measure the rotation of the earth (or thereabouts). The current atomic clocks measure microwave emissions, of changing electrons. These have been, arbitrarily taken to be the measurements of time. Time itself, like distance, is the measurement of an imaginary line between two points. This line does not exist in reality, it doesn't need to be measured as the objects (with respect to distance) can exist without the measurement of the imaginary line.

    Time on the other hand does indeed measure the change in an object, be that a change in location, or a change in it's physical make-up. Either way, it is measured against itself. Or rather, details about the object are recorded, and they are compared against the same object at an arbitrary measure of distance along an imaginary timeline. The details that are recorded, are the past details of the object, which no longer accord with reality. The change in state or location of the object is measured against the arbitrary microwave emissions of changing electrons.

    This means that if the case were to be stated correctly, the rate of change would be xunits of measurement e.g. 2metres per number of emissions from the changing electrons. As this is a bit of a mouthful, it is translated into a more meaningful term, that has been with humanity for quite some time e.g nano-seconds (or whatever the corresponding measurement is). This in itself is merely a comparison agains the degree of rotation of the earth, relative to its previous position.

    You'll have to fogive the poor explanation, however this cannot be taken as an indication of my understanding, rather my ability to translate my understanding into meaningful scientific terms. This is in part down to my lack of formal scientific training. However, knowledge of terms does not equate to understanding. If you could perhaps explain what it means for a potision to exist, then you may provide me with the correct terms (more than likely after a few questions) and then I can attempt to translate it into more meaningful terms for yourself.

    I must re-iterate however, that I do not suggest that time be done away with. Indeed it is a very useful measurement, just as distance is a very useful measurement. What I do suggest is that how we view time be questioned, to the extent that we view it as part of "the fabric of reality", as something that exerts influence over bodies within a system, or indeed as something that can be warped and manipulated, be discarded.

    Also, with regard to the comparison with distance. Distance is actually a measurement of a line between two separate points, as opposed to something being measured against itself. While the distance that an object travels, may appear as thought its present position is measured against its past position, it is actually those two positions represented by points, and the line between them that is measured.

    You are correct however, that both time and distance should be treated in the same manner, as units of measurement (arbitrarily derived) as opposed to being the measurement of something else. Or if they are to be seen as the measurement of something else, then the nature of the thing that they are actually measuring should be noted. With regard to time, and in particular, the atomic clock, time should be recognised as the measurement of the microwave emissions of a changing electron, relative to the degree of rotation of the earth (that is assuming that the number of emissions per second is what is taken as the unit of measurement).

    Honestly, I didn't start out with this decision. I operated on the exact same assumptions about time. However, through exposure to a wide range of information, I was lead to question those assumptions. That questioning continues, however the evidence has mounted to the extent that I am challenging the information that I have come to beleive is correct, mainly through discussion with various people, reading material, and educating myself as best as possible on the issue. Instead of accepting that it is true and operating from that axiom, I want to get the opinions of people who would be better versed in the sciences than I.

    It is not that I don't want to accept what relativity says, indeed I don't doubt its application and some of the results that verify part of the theory. I do strongly believe that the assumptions, not only of physical theories, but also of people and mankind, need to be questioned.

    I will take the results at face value, just as I will take the as yet unproven postulations at face value. I will also take the resulting inferences from Quantum Mechanics at face value, namely, the unobserved Quarks, the as of yet unproven String Theory, but most notably the postulation of parallell universes. These should certainly be taken as a potential warning signal (perhaps along with Dark Matter, Dark Energy and by definition, unobservable black holes), or at the very least, as an act of prudence, food for the contemplation of the base assumptions of the theory.

    However, just as I will take all of those factors at face value, you must also hold yourself to the same scientific principles and consider the overriding logic. The logic alone, highlights the need for the reconsideration of the assumptions.

    This will not invalidate the theory, certainly not its usefulness. Indeed it will remain a very useful principle for the measurement of objects relative to each other. I would however question its application to the absolute.
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