I'm not talking about the time it takes, but the mass of the fuel. Which is more than just doubled.
That is what equations tell you: http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.h... ( scroll to How much fuel is needed? )
That is what equations tell you: http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.h... ( scroll to How much fuel is needed? )
I wonder if you could accelerate the whole way in a giant ship, and only slow down a tiny capsule at your 'destination' - maybe just a tiny self-replicating robot factory and some data storage. Decelerate that, land it, have it build you a new body, some tools, etc., etc.