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Re:Scientists Capture a “Sonic Boom” of Light by whatshisface on Monday January 23, 2017 @11:07PM (#13468724)
No, there's no (experimentally supported) theory that would work at all with an object going faster than light. It just isn't in the geometry - asking for a hyperbolic rotation that stretches your motion's vector past c is like trying to turn an apple around in your hand in a way that makes it twice as big.

What they're doing here is based on the fact that you can make light move at under c if you force it to travel through a dielectric material. The c in E=mc^2 is the speed of light in a vacuum: not necessarily through a carefully designed atomic obstacle course.

Re:Scientists Capture a “Sonic Boom” of Light by ianai on Tuesday January 24, 2017 @02:33AM (#13469500)
Light always travels at c. It may appear to an observer to travel slower than c if it is being absorbed and emitted through media along the way.
Re:Scientists Capture a “Sonic Boom” of Light by snarfy on Tuesday January 24, 2017 @10:05AM (#13471834)
It's not due to absorption/re-emission. The vacuum permittivity and permeability of free space is different than a medium.

https://en.wikipedia.org/wiki/Vacuum_permittivity

https://en.wikipedia.org/wiki/Vacuum_permeability

Free space has an electrical resistance of about 376 ohms.

https://en.wikipedia.org/wiki/Impedance_of_free_space

Re:Scientists Capture a “Sonic Boom” of Light by passwd on Wednesday January 25, 2017 @06:15AM (#13480467)
>Free space has an electrical resistance of about 376 ohms.

Impedance, to be precise. If free space had electrical resistance of 376 ohms, our world would be much stranger place than it is now.