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Thread: Question on the theory of Relativity.

  1. #1 Question on the theory of Relativity. 
    New Member the great Gizmo's Avatar
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    Question for those who fundamentally understand the General Theory of Relativity. There's a lot of you here, I see.

    I'm struggling the with the fundamental concept that light runs at the same speed for all freely moving observers. I'm not trying to say it's false, not at all. A ton of technology is based on the idea.

    I just don't understand it completely.

    Light is "leap frog" pattern moving between electricity and elctro magnetism skittering across the universe, to borrow a textbook description. If you chase after this phenomena, or chase the light wave, as if trying to follow along a wave in the ocean, you'll never catch it. Even at 90% the speed of light, you will perceive it moving away from you at the speed of light.

    I understand the swelling/shrinking of mass, and energy becoming mass just fine. Where I fail is why does the observer have this effect? A stationary observer sees light moving at, well, the speed of light. If that speeding ship, going 90% the speed of light, rushes through the same field of light, he will still perceive light at the speed of light, not, as the ether theory suggest, the speed of light + or - the speed of the observer.

    Also, if you rush toward a light source, say, Proxima Centauri (4 ly), the closest star, and watched a clock on it, if you could watch that clock, rushing to it AT the speed of light, Why would 8 years not pass? The light emitted from the planet would be 4 years delayed, and it would take 4 years to get there. To me, time would not be defied in this instance. What fundamental piece of understanding am I lacking?

    I understand that the way I view this is the old world, Ether theory. That light moves at a fixed speed, if you approach it, it speeds up, if you move away, it slows down. This is what relativity disproved, along with absolute time, I just can't completely grasp Einstein's full vision.

    Any helpful words, or articles?


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    I think it has soemthign to do with the faster you get to the speed of light the more your mass increases and the more time slows down for you, meanwhile the speed of light remains constant. Since time is slowing down for you, from your perspective, the speed of light remains the same.


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    Is time dilation just a mathematical construct? As in, have we ever had an actual observer experience time dilation or are all of our experiments simply clocks on jets? I've read many alternative explanations to time dilation, I'm curious if any specific experiments have been done by say, astronauts in ~7.8 km/s orbital flight.
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    In October 1971, Hafele and Keating flew cesium-beam atomic clocks, initially synchronized with the atomic clock at the US Naval Observatory in Washington, D.C., around the world both eastward and westward. After each flight, they compared the time on the clocks in the aircraft to the time on the clock at the Observatory. Their experimental data agreed within error to the predicted effects of time dilation. Of course, the effects were quite small since the planes were flying nowhere near the speed of light.

    No matter how fast one is travelling, you are always going 0% the speed of light, since moving through space is equivalent through moving through time since time and space are interwoven and inseperable.

    in fact, if you left the earth at what people on earth perceived was the 99.9% the speed of light, and then everything else in the universe suddenly exploded, leaving only you and light, you would have no perception of movement at all since light is the only thing moving you would assume you are standing still.

    What gets weird is that if we put the earth back in the universe, you begin to notice that neither your speed or the earth's speed in relation to the speed of light is changing, you both perceive light going the same speed. This means that your space-time is separate from the earth's, and your perception of time and space are separate as well.

    This means that even though you are expending the energy to move at what is perceived on earth to be 99.9% the speed of light, General relativity states that from your perspective you are simply using alot of energy to stay still at 0% the speed of light while you watch the earth leave you at 99.9% the speed of light, meaning that if you looked back at the earth, time appears to be going slower for the inhabitants of earth rather than for you, whereas they perceive time going slower for you than it is going for them.

    We are a long way from witnessing the major kinds of these effects of time dilation, since the fastest thing we have managed to build so far, the voyager probe(s), is still only a second or so off from our time. It will take huge amounts of energy for the more serious effects of time dilation to be experienced.
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    I definitely understand the phenomenon of time dilation and cannot argue with the findings of the experiments, my question is more in regards to whether classical time is actually the cause.

    According to the deBroglie Hypothesis, all matter has a wave-like nature. This deals generally with matter on the atomic scale, and we see that the wavelength is inversely proportional to the momentum of a particle. When we accelerate an object to high velocities, the wavelength of matter decreases. Since atomic clocks operate on the periodicity of electrons, one sees more electron cycles in the same amount of time as seen by an outside observer. I've been racking my brain to reconcile this for a while, since according to the above, time should actually move faster as velocity increases because frequency is increasing. I've read research claiming that Lorentz Contraction would somehow cause a lower electron frequency at higher velocities, but I can't wrap my head around this: contracting the wavelength would, again, increase the frequency.

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    I think I've progressed my thinking, though I'm still digesting this information. According to Wikipedia's page on the Lorentz Factor, an object moving with respect to an observer will be seen to move in slow motion given by multiplying its actual elapsed time by gamma. It's length is measured shorter as though its local length were divided by gamma.

    So for an object moving at 86.6% the speed of light (0.866c):

    β = 0.866
    g = sqrt(1 - β<sup>2</sup>) = 0.5
    γ(gamma) = 1/g = 2

    If the object is 10ft long and is doing something that takes 10 seconds, from the stationary observer:

    γ*time = 2*10 = 20s
    length/γ = 10/2 = 5ft

    The object contracts to 5ft and its action now takes to 20s. If periodic events slow down at higher velocities, then the frequency of the electron waves from my previous post would have to slow down (extension by gamma or 'time dilation'), while the wavelength would shorten (reduction by gamma or 'length contraction'). This still seems strange to me since we're getting both a reduction in frequency and a reduction in wavelength even though they're inversely proportional. Theres definitely something more to this.
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    Quote Originally Posted by Frenchi
    Is time dilation just a mathematical construct? As in, have we ever had an actual observer experience time dilation or are all of our experiments simply clocks on jets? I've read many alternative explanations to time dilation, I'm curious if any specific experiments have been done by say, astronauts in ~7.8 km/s orbital flight.
    Time dilation has been shown when satellites are sent into space. The flow of time on the satelitte has to be recalibrated to equal the flow of time on Earth.
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    Quote Originally Posted by BumFluff
    Time dilation has been shown when satellites are sent into space. The flow of time on the satelitte has to be recalibrated to equal the flow of time on Earth.
    Right. I'm familliar with autonomous experiments done with atomic clocks, and I don't doubt the results. Theres definitely a lag in the recorded time of the clocks, I'm just not entirely convinced that the cause is time dilation; the problem might instead have to do with the way atomic clocks measure time. If the frequency of the electrons being scanned were changed, the clocks would give time incorrectly. One could say that since the frequency is in fact slowed, it's because of time dilation, but I keep seeing this as a mechanical slowing instead of a function of time. For example, when we cool a substance, its molecules slow down, but we don't say that time is passing slower for the object, it's just less energetic. For fast moving cesium clocks, the velocity is having some kind of an effect on the elementary particle's waves causing the frequency to slow, in turn causing the clock to register less time than as observed by a stationary oberver.

    I don't have any definitive proof for this, and I don't want to send poor Gizmo's thread spiraling into pseudoscience, it's just one of those nagging issues of scientific scrutiny bubbling in the back of my skull. As a strictly observational assessment, there undoubtedly appears to be the effect of 'time dilation', whether time dilation is the cause or merely a coincidental apparent effect. If I progress this line of thinking any further I'll open a new thread for it.
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    Thank you everyone. I've been working overtime and i had poker tourney tonight and I've been drinking, so, not really in a state of mind to wrap my brain around this. Tommorow evening, if you're still active here, I'll have my response, because I do still have a few questions. It seems to me as all the observable effects can still be explained with the ether theory, if not more so.

    Once again, I'm still sure I'm wrong, not trying to question it (Yet, you can't just openly accept something if you don't come the same conclusion.) However, I still think I'm just missing info.

    Thanks again, see you all tommorow.
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    Quote Originally Posted by Frenchi
    Is time dilation just a mathematical construct? As in, have we ever had an actual observer experience time dilation or are all of our experiments simply clocks on jets? I've read many alternative explanations to time dilation, I'm curious if any specific experiments have been done by say, astronauts in ~7.8 km/s orbital flight.
    GPS satellites are ongoing experiments in time dilation as they must be constructed for velocity and gravitational time dilation.
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    Further to the above:

    "During October, 1971, four cesium atomic beam clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40+/-23 nanoseconds during the eastward trip and should have gained 275+/-21 nanoseconds during the westward trip ... Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59+/-10 nanoseconds during the eastward trip and gained 273+/-7 nanosecond during the westward trip, where the errors are the corresponding standard deviations. These results provide an unambiguous empirical resolution of the famous clock "paradox" with macroscopic clocks."

    J.C. Hafele and R. E. Keating, Science 177, 166 (1972)
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    Quote Originally Posted by Ophiolite
    Further to the above:

    "During October, 1971, four cesium atomic beam clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40+/-23 nanoseconds during the eastward trip and should have gained 275+/-21 nanoseconds during the westward trip ... Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59+/-10 nanoseconds during the eastward trip and gained 273+/-7 nanosecond during the westward trip, where the errors are the corresponding standard deviations. These results provide an unambiguous empirical resolution of the famous clock "paradox" with macroscopic clocks."

    J.C. Hafele and R. E. Keating, Science 177, 166 (1972)

    Those planes are being flown very near the distortion between space and the atmosphere. There is a swirling or mixing effect taking place right there.
    And the swirling effect where the two different density gases touch are moving at many times 1500 feet a second. If you did not get distortions I would be surprised. This effect is what changes the direction of the compass on the ground. Imagine the power it has right near the event.

    However I could shield those clocks and stabilize the voltage they are situated in. And there would be no time recording difference.

    So in my opinion they just did a lot of experimenting with about a thousand unexplained phenomena and variables not accounted for.

    Years ago they were talking about these same things, hundreds of years before Einstein. And you could have had your head chopped off for saying that the earth was not the center of the Universe. Or saying that the earth was hurling through space.

    To do that clock experiment and knock out all the variables would be to prove what I am saying. So I am sure they don't want to knock out the variables.

    The very purpose of this experiment is flawed. Obviously.



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    Why would you gain time with the westward trip?
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    I'm guessing it has something to do with the additional speed gained with following the spin of the earth as opposed to going against it.
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    Quote Originally Posted by Cold Fusion
    Why would you gain time with the westward trip?
    Because the relevant velocities in this experiment is relative to the inertial frame of the center of the earth, and thus the westard journey is actually a lower velocity compared to simply standing on the surface and only on the eastward journey are you going faster.

    You experience this on long plane flights in the following way: Traveling east the sun rises and sets a little more quickly and traveling west the sun rises and sets much more slowly. This means that on the eastward journey you are moving faster than the surface of the earth and on westward journey you are moving slower than the surface of the earth. If you went fast enough in the westward direction, you could travel with the sun always over head (which is not moving much at all relative to the center of the earth and the sun) - but you would have to be fast enough to go all the way around the world in only 24 hours.
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