Up to this point every interstellar propulsion method has assumed that it would be carrying along a large payload of humans, life support and supplies. Because of this every proposal has yeilded ship designs that are several hundred meters long. Project Daedulus, Orion, and the Bussard Ram Jet are all enormous vehicals with huge energy requirments. The antimatter rocket designs were also demanding, with tons of matter and anti-matter required to make it work.
So what if there were no payload requirments? Assuming we have complete nanotechnological control over matter, what is the absolute smallest we can make a self-propelling ship (no outside lasers, etc) that is capable of travelling close to the speed of light and slowing down again at its destination star?
If we exist as uploads requiring the absolute minimum amount of computronium to run on, then the only constraint is the size of the ships components themselves.
Does anyone have a clue what the smallest possible .99c ship that can be constructed using nanotechnology, and the constraints of physics?
Paul Hughes