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View Full Version : How A Laser Appears To Move Faster Than Light (And Why It Really Isnít)



Fraser
2014-Feb-07, 06:00 PM
We at Universe Today often hear theories purporting that Einstein is wrong, and perhaps one of the most common things cited is the speed limit for light*used in his relativity theories. In a vacuum, light goes close to 300,000 km/s (roughly 186,000 miles a second). Using a bit of geometry, however, isn’t there a way […]

More... (http://www.universetoday.com/109147/how-a-laser-appears-to-move-faster-than-light-and-why-it-really-isnt/)

swampyankee
2014-Feb-07, 08:37 PM
There's something called, iirc, phase speed in a wave guide, which can exceed the speed of light. Since it can't carry information, there's no SR violation. Obviously, if there was an SR violation, something would have to be done.