Quote Originally Posted by Khendraja'aro View Post
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That can't be right. C=299,792,458 m/s, 1g=9.8m/s^2, so to get to .5c dividing it would take 1.53E07 seconds = 2.55E05 minutes = 4.25E03 hours = 177 days = ~.5 years to reach that speed. Since you can cover the distance in 20 years at that speed, it can't possibly take 8 trillion years to get there.

edit: I did the math myself, using an equation I stole from here and came out with ~12 years assuming constant 1g acceleration & deceleration. I assumed I screwed something up because it's such a small number, but from the above calculation it actually seems believable. If it's right though, that still sidesteps the issue of where the hell we're going to get that much energy.