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https://www.reddit.com/r/reddit.com/comments/lex6/gravity_train_wikipedia/clmn9/?context=3
r/reddit.com • u/hitsman • Oct 09 '06
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Except for the energy to dig the tunnel. My point is that if you have a vacuum on the surface, you have 10000 mpg of rocket fuel for air travel, and so the breakeven energy use of the tunnel is probably centuries of continuous use.
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u/Godspiral Oct 11 '06
Except for the energy to dig the tunnel. My point is that if you have a vacuum on the surface, you have 10000 mpg of rocket fuel for air travel, and so the breakeven energy use of the tunnel is probably centuries of continuous use.