quote:
Originally posted by John Anderton
At 0.99999999*c you would take about 76 or so years to reach the nearest star so excuse me for thinking that travelling at the speed of light won't give us shit.
All we can use (for travelling at v->c) is to travel within the solar system quickly. If you want interstellar travel, you my friend need to travel faster than light. Warp travel 
Gogo Star Trek(ie) 
(
)
Sigh, learn physics
at the speed you quoted it would only take 5.2066272
HOURS - my estimation of a few seconds was under more of an assumption of 0.99999..9 (to many decimal places). But 76 years is absolute rubbish...
You're even wrong in Newtonian Physics, using Newtonian Physics it would only take just over 4.2 years (since the nearest star is 4.2ly and you're almost travelling at the speed of light)
quote:
Originally posted by CookieRevised
This is because time slows down the faster you travel. This has even been proofed IIRC, by sending an atomic clock to space and when it came back it was several thousands of a microsecond further.
Yes you are 100% correct about time dilation and time passing slower in the moving frame of reference (ie. for the person/object that is moving), although the proof wasnt quite as easy. At school they teach that experimental evidence was provided by synchronising 2 atomic clocks and sending one around the world in a plane, when they were returned the one which was moving (on the plane) was noted to be running behind the one which remained grounded, in reality however, gravity also affects time and space and as such the results were not as simply due to Special Relativity alone (it has however since been proven using more complex reasoning).
Another source of evidence was given by radioactive particles which are created when radiation from the sun hits the atmosphere (or something like that), whilst these particles (cant remember the name of the specific particles which are most often noticed) have a half-life of about 2 microseconds and as such many are not expected to reach anywhere near the surface of the earth before they decay, however, their extremely high velocities result in them reaching the surface in a greater quantity than would be predicted indicating that time for these particles has advanced slower, and hence it has taken longer for them to decay relative to us on the ground.
/ 
