RE: starship-design: scoops and sails and something to push against.

["L. Parker" <lparker@cacaphony.net>]

Zenon,


> Statically probably yes.
> Hence Kevin wrote about pulsing the fields in some way.
> That might work, like the similar trick with pulsing
> magnetic fields in electric motors.

I read somewhere once about a stardrive that relied upon pulsed magnetic
fields created by air-core magnets. The idea was to switch them on and off
in such a way that the fields were not conserved locally, but were conserved
globally so there was no violation of physics involved...I also seem to
remember a column by John Cramer explaining why it wouldn't work.

I'm no physicist, but I don't think it will work. This is an excellent
example of why they want to create or find a magnetic monopole. Steve or
David can probably give you a better explanation than I can.

I'm afraid the best we can hope for in the time frame we are discussing is a
first or second generation fusion engine or hybrid antimatter/fusion engine.
In truth, we can design a ship around a drive that can get a small vessel up
to 0.3 c. It won't be as fancy as Kelly's Explorer, but we should be able to
put a crew of 5 to 10 people on Alpha Centauri after a 12 year flight. Kind
of long, but doable. Tau Ceti of course would take longer, probably at least
thirty years one way. We would have to put a crew of twenty year old
astronauts aboard and expect them to get back when they were eighty!

Lee