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What determines the velocity of light?

  1. Jun 3, 2009 #1
    What determines the velocity of light???

    What determines the velocity of light???
    OK since the velocity of light is finite there must be a factor determining the magnitude, right??

    We know the velocity of a wave travelling through a liquid is determined by the viscosity of that liquid, and the velocity of a physical wave travelling through a gas is determined by the thickness or density of the gas, for example the speed of sound through air is limited by the thickness (or more accurately "thinness") of the air it is travelling through. The same is true with the density of solids.

    So we can conclude that the velocity of a wave is determined by the thickness of the medium it is travelling through, OK? This makes perfect sense because of Newtons second Law of motion, since denser mediums are bound by greater force and thus any wave travelling through it will have less and as a result be slower.

    The same can be observed with electromagnetic radiation like visible light, and sure enough light is slower through denser mediums.

    But what determines the velocity of light trough a vacuum???

    According to my theory of light-mass-dynamics it is Heat and Voltages and other Electromagnetic radiation, as well as a thing I call cosmic pressure.

    What do you think???

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    In Love
    Prys die Heer!
     
  2. jcsd
  3. Jun 3, 2009 #2

    malawi_glenn

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    Re: What determines the velocity of light???

    [tex]c = 1/\sqrt{\epsilon _0 \mu _0}[/tex]

    where [tex]\epsilon _0 [/tex] is the permittivity of the vacuum and [tex]\mu_0 [/tex] is the permeability of the vacuum. This is taught in standard interlocutory classes in light and optics and electromagnetism.

    Regarding your theory, please read and follow our forum rules regarding own speculations/theories.
     
  4. Jun 3, 2009 #3
    Re: What determines the velocity of light???

    Thank you MG.

    I was not trying to discuss my theory, I simply wanted other peoples opinions on the matter and thus shared my own.

    Anyway is this a good place to debate, I don't want to break any more rules.
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    In Love
    Prys die Heer
     
  5. Jun 3, 2009 #4

    malawi_glenn

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    Re: What determines the velocity of light???

    what is the point developing own ideas when one has not understood current knowledge and where the anomalies are?

    And "heat" is not so specific... what KIND of heat? Define Heat, have you done courses in statistical mechanics and thermodynamics?
     
  6. Jun 3, 2009 #5
    Re: What determines the velocity of light???

    Maybe a good thing to mention here is that the speed of light is a defined quantity. We defined it to be 299 792 458 m/s exactly. Since the second is also defined exactly, we can then define a meter as the distance light travels in 1/299792458 of a second.

    We could define the speed of light to be 1 m/s if we wanted, but that would radically change our world. A meter would then be the distance light travels in 1 second, which is MUCH MUCH MUCH more than what a meter is now!
     
  7. Jun 3, 2009 #6
    Re: What determines the velocity of light???

    The velocity of sound in air is nearly completely independent of temperature, and of atmospheric pressure. If this were not true, musical instruments like flutes and clarinets would have to be constantly retuned whenever the barometric pressure or temperature changes. You need to work out from basic principles the theory of sound in air. You will find that it is proportional to the square root of pressure divided by density. Why do I believe this is correct? Pressure is force per unit area = kilogram meters/sec2 per meter2, and density is kilograms per meter3, so the square root of pressure over density = meters/sec. So how does viscosity theory fit in?
     
  8. Jun 3, 2009 #7
    Re: What determines the velocity of light???

    Good question MG, but let me ask you an even better one, how do you expect to build or find the foundation of science if you do so upon the theories of others? Wouldn't that result in an up-side-down pyramid, that has no foundation at all?

    See I'm trying to find a theory of everything, and thus a theory that is independent of other theories. I Don't want to study any other theories, since a theory of everything renders them all obsolete.

    Well I would have to explain my theory for you to understand, but it comes down to the temperature of the vacuum.

    But how Nick??

    It comes down to the bonds between the air particles.
    See if something(like sound) has greater force resisting it (like the forces between the particles) it will have an lower resulting force, and thus be slower. For example sound travels faster through helium than air.

    The small differences will not easily be observed because the variations in temperature and atm is generally very small, in comparison to the amounts required to change the strength of the bonds.

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    In Love
    Prys die Heer!
     
  9. Jun 3, 2009 #8
    Re: What determines the velocity of light???

    Thanks for the insights into the kind of mindset that drives people to make up their own theories without studying the ones that already exist. Unfortunately such an approach is doomed to failure, it is a complete waste of time. It's not too late to learn physics and one day do original research, you should abandon the hopeless quest for a personal theory of everything.
     
  10. Jun 3, 2009 #9

    Doc Al

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    Re: What determines the velocity of light???

    On this note, thread closed.

    Please review the Physics Forums Global Guidelines, in particular the section on Overly Speculative Posts.
     
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