Does light always travel at c relative to any observer or object?

[devious_]

If a spaceship is traveling at c and a beam of light is emitted through it. The beam of light would be traveling at c relative to the object. Correct?

How about if there's an observer, what would the speed of the beam of light be relative to him. c?

And if the spaceship was instead traveling at 0.6c, would the speed of light relative to it still be c?

 

[Doc Al]

Yes to all: The speed of light with respect to any object or observer will be c.

 

[devious_]

Great. Thanks. :)

 

[pervect]

If a spaceship is traveling at c

A spaceship can't travel at c, though it can get arbitrarily close.

 

[pmb_phy]

A spaceship can't travel at c, though it can get arbitrarily close.

Well... there is that whole Alcubierre warp drive thingy.

E.g. see Fundamental limitations on "warp drive" spacetimes, Francisco S. N. Lobo, Matt Visser, Class.Quant.Grav. 21 (2004) 5871-5892

Online at - http://xxx.lanl.gov/abs/gr-qc/0406083

Pete

 

[Doc Al]

If a spaceship is traveling at c

A spaceship can't travel at c, though it can get arbitrarily close.

Oops... I must have missed that statement by devious_ in my quick reading. Good catch, pervect.