Quote:
Originally Posted by jgray
FTL may be impossible, given our current knowledge. However, if someone discovers a way to get from point A to point B without travelling through the intervening space, you aren't really travelling FTL. Of course, I'm talking about subspace, hyperspace, warp drive, jump drive, skip drive, etc. as used in many SF stories over the decades. I don't think we'll every see it, but I don't discount the possibility that some future generation will.
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Let's get our definitions straight. Speed of light is usually defined as the speed of light in a vacuum. There is a loophole in Maxwell's equation's boundary conditions that describes that.
Maxwell's equations have two boundary conditions. 1. the electromagnetic wave needed to have a right hand twist, and 2.
c, the speed of light had to follow the following equation,
c = 1/square root of (permeability of medium and permittivity of medium). Until 1999, permeability and permittivity were considered constants, requiring the speed of light to be a constant.
In 1999, a team at Cal San Diego found a way to create a resonance (at microwave length) that allows both permeability and permittivity to be changed and made negative. Experiments with this resonance (nicknamed left-handed materials), have shown a complete inversion of the Laws of Optics, such as Snell's Law. In addition, the first boundary condition of Maxwell's Equation, the right hand twist, became a left-hand twist, with the appearance the while the beam was moving towards the target, the propagation form seemed to be moving backward.
The second boundary condition implies that as the permeability and permittivity approach zero, the speed of light should approach infinity. For some reason, this boundary condition has not been tested. One test was done in 2003, by using mis-aligned surfaces over a short distance (45 nanometers) to mimick the field condition, which shown no change in
c. Unfortunately, surface effects are not field effects. The question remains open...
If you can speed up light in a field with low permeability and permittivity, that would break the classic [I]c[/]. This would not violate both Relativities, merely expand the defintion of
c in them into a variable rather that a constant. If you can't, then you've busted Maxwell's Equations. Either way, an interesting experiment.
Of course, making it apply across all wavelengths with be an interesting piece of engineering....