blike Posted July 20, 2002 Share Posted July 20, 2002 Hubble's law states that there is a linear relationship between distance and recessional velocity, correct? Following this line of thought, wouldn't there be very distant galaxies that are traveling faster than light? How is this not a violation of special relativity? Link to comment Share on other sites More sharing options...
fafalone Posted July 20, 2002 Share Posted July 20, 2002 Light is the same speed for all observers. Two beams of light going in the opposite direction wouldn't appear to be twice as fast as light normally does. Very weird stuff :/ Link to comment Share on other sites More sharing options...
Radical Edward Posted July 20, 2002 Share Posted July 20, 2002 I think he means you should be able to see the galaxies whizzing away at velocities >c this would play havoc with red shift. I can't say really, I'm not sure, as I was never so big on cosmology. Link to comment Share on other sites More sharing options...
fafalone Posted July 20, 2002 Share Posted July 20, 2002 That's what my post addressed, you wouldn't see that. Link to comment Share on other sites More sharing options...
blike Posted July 20, 2002 Author Share Posted July 20, 2002 Not that faf Hubbles law explains that the further away a galaxy is, the faster it is moving away from us. Hubbles law: V=H0r H0 is the hubble constant, and r is the distance (in mpc) Now, if r(being distance) > (c / h0) then V > c, which means the galaxy is moving away from us faster than light. Galaxies which have a distance greater than c/H0 are moving away from us faster than the speed of light; how is this not a violation of known laws.. Link to comment Share on other sites More sharing options...
blike Posted July 21, 2002 Author Share Posted July 21, 2002 I'm gonna bump this up. Link to comment Share on other sites More sharing options...
fafalone Posted July 21, 2002 Share Posted July 21, 2002 if v = h0 * d, with v in km/sec (h0=km/sec/mpc, d = mpc... using h0 = 75), then in order for v =< c, d>=39,997,232,773 parsecs = 130,375,098,531 light years... the universe isn't 130 billion years old according to most models Link to comment Share on other sites More sharing options...
Radical Edward Posted July 21, 2002 Share Posted July 21, 2002 we'll have to wait around for a while then.... Link to comment Share on other sites More sharing options...
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