> “At 99.999% C, the traveler would take ~11,000 years to arrive to Andromeda.”
So presumably this means 11k years from an earth point of view? But the traveler would still be alive and a very short time would have passed for him?
So presumably this means 11k years from an earth point of view? But the traveler would still be alive and a very short time would have passed for him?
At 1g of constant acceleration you can reach Andromeda in just under 15 years of experienced time. An observer on Earth will perceive you as having taken a hair over 2,500,000 years to get there. You can get there arbitrarily quickly; at 10g it would take a 1 year 9 months. But an external observer on either planet will see you taking closer and closer to 2,500,000 years to make it the full distance.
Whereas a constant 1g acceleration would far exceed that fraction and thus shorten the time significantly.
When you say constant 1g acceleration, do you mean acceleration well past the speed of light? I thought we were talking about all speeds less than the speed of light.
The Lorentz factor, which governs time dilation and length contraction, is calculated as (1 / sqrt(1 - v^2 / c^2)), where v is the relative velocity of the object and c is the speed of light. You can replace (v^2 / c^2) with the factor beta^2, where beta is the ratio of v to c, e.g. 0.99999 in this case. Since (1 / sqrt (1 - 0.999...)) grows without bound in the limit as beta approaches (but doesn't reach) 1, if you keep accelerating, the time dilation keeps getting larger, without limits. It just takes a LOT of energy to do so.
I was still at a loss for the answer to how it could take 11k vs 28 years or so. I asked AI. lol
The thing I didn’t realize is the massive difference between 99.999% vs 99.9999% of the speed of light. I took 99.999% to mean "effectively the speed of light.” Relativity is weird.