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The speed of light in a vacuum

  1. Aug 31, 2005 #1
    the speed of light in a vacuum....

    the speed of light in a vacuum is a true constant of nature, independent of the wavelength of the light or the choice of an (inertial) reference frame. is there any sense, then, in which einstein's second postulate can be viewed as contained within the scope of his first postulate?
  2. jcsd
  3. Aug 31, 2005 #2
    You have been reading sci.physics.relativity haven't you? This has been discussed regularly there and you know that the light postulate is not needed to formulate the Lorentz transforms.
  4. Sep 2, 2005 #3
    Einstein's second postulate actually related only to the independence of the velocity of light on the velocity of the source - not the receiver - the independence of the velocity of the receiver relative to light follows from the first postulate.

    Specifically, the second postulate is: "Any ray of light moves in the stationary system of coordinates with the determined velocity c whether the ray be emitted by a stationary or moving body.."
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