The speed of light varies, depending on the medium. Albert Einstein stated that light is the fastest moving thing in a vacuum, with its speed being roughly 186,000 miles per second. In water for instance, the speed of light slows down to 140,000 miles per second. Its speed is 124,000 per second in glass. In a diamond, the speed of light is 77,500 miles per second. The speed of light through vacuum is said to go as fast as it gets.
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However;
Three quasars and one galaxy possess structures that apparently expand faster than light. The sizes of the three Quasars were measured over periods of time by Very Long Baseline Interferometers (VLBIs). In the case of quasar 3C279, the apparent velocity of expansion was ten times (!) that of light. The quasars all have rather large redshifts, indicating great distances from earth, but the lone galaxy displaying "superluminal" expansion has a redshift of only 0.032. This fact suggests that superluminal velocities cannot be employed as arguments against redshifts being cosmological; that is, measures of distances from earth. Therefore, if the redshift is truly a measure of distance (as it seems to be), some astronomical structures (perhaps not matter itself) seem to grow faster than the velocity of light.
(Cohen, M.H., et al; "Radio Sources with Superluminal Velocities," Nature, 268:405, 1977.)
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Already scientists are inventing faster than light particles.
A tachyon (pronounced /ˈtækiˌɒn/; Greek: ταχύς, takhus, "swift" + English: -on "elementary particle") is a hypothetical subatomic particle that travels faster than the speed of light. In the language of special relativity, a tachyon is a particle with space-like four-momentum and imaginary proper time. A tachyon is constrained to the space-like portion of the energy-momentum graph. Therefore, it cannot even slow down to subluminal speeds.
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-Speed-of-light
experiments give baffling
result at Cern. -
Puzzling results from Cern, home of the LHC, have confounded physicists -
because it appears subatomic
particles have exceeded the
speed of light.
Neutrinos sent through the ground from Cern toward the Gran Sasso
laboratory 732km away seemed to show up a tiny fraction of a second early.
BBC News 09/22/2011
This isn’t an isolated anomaly, but has been going on for years. The team has now measured some 15,000 batches of neutrinos coming across that distance, and they say they’ve reached a point where the statistical significance is such that, were they trying to prove anything else, it would count as as formal scientific discovery. But try as they might, they can’t explain what’s happening. popsci.com 09/22/2011
The transfer of information between twin particles seems to go faster than light as well.
Or maybe it is all part of the illusion.