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Relativity is broken!

  1. Jan 6, 2006 #1
    Ok so here it goes.

    -As you approach the speed of light, time slows down. Shown with the atomic clocks, one in the plane, one stationary.
    -at speed of light time would stop.
    -above speed of light, time would reverse. unlikely but whatever

    However isnt also the speed of light dependant on time. as speed is distance/change in(delta) time.

    so if time has stopped for light itself, the speed isnt happening. and if no speed, no special mass and as light has no mass, it doesnt have rest energy.

    so logically light doesnt exist if its true for the original -
  2. jcsd
  3. Jan 6, 2006 #2


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    The speed of light is not a valid reference frame for measuring/calculating speeds in other frames since nothing other than light can achieve it.
  4. Jan 6, 2006 #3


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    Correct. Photons do not experience time at all.
    No. Our measurement of something's velocity uses time (as in distance over time), but we are measuring it from our own reference frame, not the object's. Measuring an object's speed in our own reference frame does not require the object itself to experience time. In fact, note that the object CANNOT measure its OWN speed (except by referring to another reference frame.)
    Last edited: Jan 6, 2006
  5. Jan 6, 2006 #4


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    Well, in its own frame an object's speed is zero, its clock is running at the rate one second per second and its metre rule is just one metre long.

    i.e. in any object's rest frame clocks and rulers behave as you expect them to!

    munky - why do you think relativity is broken?
  6. Jan 6, 2006 #5


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    Right. Speed is a meaningful concept only when comparing to other things.
  7. Jan 7, 2006 #6
    It results from an abstract structure

    There is another view of this problem I like to point to.

    According to Louis de Broglie, a photon does not move at the theoretical speed of light, but is a very small amount slower than that. Also the mass of the photon is not exactly zero but extremely small.

    An object like a photon with zero mass is a singularity in a mathematical system. This is (most probably) not possible in a real physical system.

    It is a speciality of the spiritual world of Einstein, that he understands physics as a structure (following the Greek philosopher Plato). It is remarkable that Einstein follows this way only in the context of relativity. In the context of quantum mechanics, which according to main stream physics is also based on structures, Einstein has always objected.
  8. Jan 7, 2006 #7
    actually ive thought of that i was going to add it. Ive never heard of Louis de Broglie or anything of this before.

    I dont know how he come to that conclusion. But once in high school physics we were taking up how light changes speeds in different materials. then i pointed out that space isnt true space, there is always some matter roguely flying around space thusly making untrue vacuum. it may be 99.99999% vacuum, but there is always that one particle or something. thusly making the speed of light just slightly less then the true exact limit.

    then taking into above account, to the photons time goes extremely extremely slow, but there is time, then what ive stated makes sense.

    if light in space is proportional to how true the vacuum is. then the true speed of light isnt a constant, its simply relative.

    if light speed is relative to the trueness of the vacuum. back near the big bang, light would be very slow compared to now, since the space between atoms are moving apart basically because of the expansion of the universe.

    exact opposite of what creationists want. Example
  9. Jan 7, 2006 #8


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    No it doesn't, because you are ignoring the MECHANISM on why, in a medium, the speed of light differs from the vacuum value.

    First of all, you need to understand what exactly is meant by the speed of light in a medium (hint: learn the meaning of phase and group velocity). Secondly, do you really think a scattering with an occasional particle in vacuum would truly affect the speed of light? Can you please show this, for example, in a Compton scattering? The optical transport in a more dense medium (such as gas) is also different than an optical transport in a solid medium (such as glass). Without understanding the mechanism on what causes light to change "speed" in such situations, you are opening yourself up to making unsubstantiated and unverified speculations.

    I would like to remind you that speculative posts are only restricted to the IR section, per our Guidelines. This has gone off from asking to speculating based on an incomplete knowledge of Special Relativity and Optics. If you wish to do that, then it should be done only in the IR section, not here.

  10. Jan 7, 2006 #9


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    [Edit: crossed with Zz]
    You have to distinguish between the nature of the space-time continuum with transformations between different frames of reference on the one hand and the physical behaviour of photons and particles within that continuum on the other.

    If you are going to say that the velocity of light is variable then you have to describe precisely how you are making that measurement of velocity. You need rulers and clocks, so perhaps it is your ruler and clock that are varying w.r.t. to each other? This would mean the spatial and temporal structure of the atoms out of which your rulers and clocks are constructed are varying, which means most probably that the fine structure constant is varying.

    Such Variable Speed of Light theories have been suggested, but they cannot be proposed in a naive way.

    The fine dust and gas in ISM does not influence the speed at which light travels through it. The medium needs to constantly absorb and re-emit the photon to influence its speed, in the ISM the light path from star to observer for most photons is unbroken.

    Last edited: Jan 7, 2006
  11. Jan 7, 2006 #10
    To be honest i dont even know what your asking here. If its the old experiment with Light hitting gold that released electrons when they absorbed the light. Alright cool. Dont really know how to do that, but sure.

    Well im not saying that the speed of light would be effected in any meaningful way. Im just saying that those very few particles must have an effect regardless to how negligable that is.

    the result may be 99.999999999999999999999999999999999999999999999999999999999999999999999999999999999% still being transmitted fine, and that very tiny % means nothing, but its legitimately there.

    Take this for example.
    You take you density and measure the speed of light in 1 atmosphere on earth through air.
    Then you do the same thing with .75 atmospheres. a slightly more vacuum. and the speed of light will increase. even though its almost nothing. then keep lowering that # until u get to that .00000000000000000000000000000000000000001 atmospheres and you essentially have space. using the line of best fit you find the constant, speed of light: c

    however. to actually say your at the speed of light would be one of those.

    .999999999999999999999999999999999999999 which doesnt mean 1.

    actually i dont recall what math says to this :)

    true. but i dunno. i havent figured that out. I was imagining as a star as reference, i emit light, and in the very large space between me and earth, there is a good chance for particles to play around, but all light wouldnt be guarenteed to be hitting anything. I dont know how to get around that obvious problem. Perhaps virtual particles come into it. Im pretty sure virtual particles can effect light, the whole pair production thing relates to using photons to making them real.
  12. Jan 7, 2006 #11
    Perhaps this is a mathematical expression of the concept that the whole is greater than the sum of its parts ?
  13. Jan 7, 2006 #12


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    0.9999.... is exactly 1. You can search the forums for the explanation of this, which has been talked about many times.
  14. Jan 7, 2006 #13
    Louis de Broglie was one of the founders of quantum mechanics. He found the wave nature of elementary particles and received in 1929 the nobel price for that.

    DeBroglie assumed that a photon is composed of 2 neutrinos. There is no direct proof for this assumption but there is also nothing in conflict with it. A conclusion of this assumption is that a photon also has a small mass as the main stream physics believe since a few years that a neutrino does in fact has a small mass.

    In one point you are right: The speed of light is not constant in vacuum. In the presens of matter at some distance the speed c is reduced. We call that effect "gravity".
  15. Jan 7, 2006 #14


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    No, in the presence of matter when climbing out of gravitational curvature the speed of light remains c, but the energy is reduced, i.e. it is red shifted. We call the effects of that gravitational curvature "gravity".

  16. Jan 7, 2006 #15

    Tom Mattson

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    For completeness, the current experimental upper bound on the photon mass is [itex]6\times10^{-17}eV[/itex].


    Can you be more specific? What singularities are predicted by SR? If you are referring to the fact that the Lorentz factor blows up to infinity when [itex]v=c[/itex] then I don't see the problem, because massive particles don't move that fast.

    I would beg to differ on that. It is well known that a system of two spin-1/2 particles can form composites with 4 spin states [itex](s,m_s)=\{(1,1),(1,0),(1,-1),(0,0)\}[/itex]. But in countless experiments only 2 states have ever been observed for the photon: [itex](s,m_s)=\{(1,1),(1,-1)\}[/itex], which is exactly what one would expect if the photon were massless.
  17. Jan 7, 2006 #16


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    And to add to what Tom said, the suggestion that a photon is made up of 2 neutrinos has another fallacy: WHICH neutrino? Electron, muon, tau? And if it is made up of one of the neutrinos, by citing the mass evidence, one must also not ignore that the neutrinos has a mixing angle. This means that the electron neutrino can mix into another form. I'd like to see that being explained to light's properties.

    This is where using snippets of outdated hypothesis while ignoring modern-day evidence can produce outrageously wrong guesses.

  18. Jan 8, 2006 #17
    Already in the 1970ies Shapiro has proven by radar ranging to the planet Venus, that the speed of photons passing close to the sun is reduced. Later such experiments were performed with high precision. They all verify the equation about this reduction of c in a gravitational field given by the Schwarzschild formalism.

    This reduction of can be applied to the internal motion within an elementary particle as it was described by Schroedinger in 1930. Then the consequence is an acceleration of this particle which we call "gravity".
  19. Jan 8, 2006 #18
    ... and how much is the mass of a neutrino please?
    A theory like SR has to be valid for all particles. The photon is a real particle and should be covered. Otherwise SR can only be taken as an approximative theory and we have to find the correct one (what many physicists these days expect to be done).
    I understand this so, that the combination necessary to build the photon is possible, but not all combinations are used in nature.
  20. Jan 8, 2006 #19
    I do not have any more details about the statement of deBroglie. I guess that at his lifetime it was not known yet that there are 3 types of neutrinos. But I understand this as a hint to which direction we could look in order to understand the photon.

    All elementary particles we know in present physics have spin=1/2. All bosons are composed of fermions. So it should be expected that also the photon is composed of something. What do modern days physics tell us about this?

    The treatment of the photon also in SR is for my understanding incomplete. The whole theory of relativity (particularly GR) is not correct which is obvious through the unsuccessful discussions about quantum gravity since several decades.

    This is when staying fixed to theories and ignoring the fact of unresolved problems.
  21. Jan 8, 2006 #20

    George Jones

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    It depends on what what one means by the speed of light. Suppose a laser beam whizzes by an observer (freely falling or accelerated). The observer, independently of where she is located, uses an orthonormal frame to make measurements, and, with respect to this orthonormal frame, the observer always measures the speed of light to be c, just as Garth says.

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