If you keep on accelerating with 1g for close to a year, you're so close to the speed of light that you can zap just about anywhere while little subjective time is occuring. So, you can go effectively anywhere in our galaxy in two years subjective time (as you have to decelerate as well).
That raises two questions for me:
1) What is the total amount of mass and energy required to do that
2) Why are reaction engines considered to be most efficient when the exhaust more or less stops dead in space, and why would the speed of the ejection mass set an upper limit to the speed you can accomplish?
I don't get the second point. Because any mass you eject at the back should increase your speed, no matter what. Yes, the faster you go, the less your speed increases by the same amount of thrust, but there should be no lower boundary. As far as I get it.
And what would be the minimum requirements for such a relativistic space ship?
That raises two questions for me:
1) What is the total amount of mass and energy required to do that
2) Why are reaction engines considered to be most efficient when the exhaust more or less stops dead in space, and why would the speed of the ejection mass set an upper limit to the speed you can accomplish?
I don't get the second point. Because any mass you eject at the back should increase your speed, no matter what. Yes, the faster you go, the less your speed increases by the same amount of thrust, but there should be no lower boundary. As far as I get it.
And what would be the minimum requirements for such a relativistic space ship?