On Fri, 19 Feb 1999 00:36:45 -0500 "joe dees" <firstname.lastname@example.org>
>At Fri, 19 Feb 1999 00:05:31 EST, you wrote:
>>"Nothing can exceed the speed of light"....
>>I've heard that many times. Well apparently that is not true. Since
>>turtle will be able to do it.
>>Only kidding here..since I've neglected the "in a vacumn" part of
>>However..that leads to a question. If light is "slowest" in a
>>Condesate..and "fastest" in a vacumn...is there anything "less" than
>>vacumn? It is possible to slow light down..is it even
>>possible to speed light up?
>>No clue here..a vacumn is a vacumn right?
>And does the frequency (wavelength) matter as to speed, either in a
>vacuum or in a Bose-Einstein condensate?
>Joe E. Dees
>Poet, Pagan, Philosopher
The speed of light (electromagnetic waves) in a vacuum is completely independent of the frequency or wavelength of the photons or waves, according to Maxwell's theory, and such a phenomenon has never been observed as far as I am aware.
But there is a theoretical possibility that light in a vacuum could be slightly slowed over cosmic distances by the presence of electromagnetic energy in the space (e.g. the cosmic background radiation, starlight, quasar light, etc.)
On a cosmic scale, the frequency of light travelling through space
becomes red-shifted as the space through which the light travels expands.
Light travelling out of a gravitational potential well (away from a star
or the vicinity of a black hole) will be red-shifted as the photons lose
energy as they climb.
Light travelling out of a gravitational potential well (away from a star or the vicinity of a black hole) will be red-shifted as the photons lose energy as they climb.
Light falling into a gravitational well is blue-shifted, all else being equal.
For media with a refractive index greater than that of vacuum, the speed of light generally varies with frequency. Glass prisms, for example, break up white light into a rainbow spectrum.
I don't know if speed varies with frequency in a Bose-Einstein condensate, but it seems likely since it does with seemingly most material media.