starship-design: Stellar drive?

[Steve VanDevender <stevev@efn.org>]

[description of reactionless drive deleted]

No one has ever built a _working_ reactionless drive that would work in
zero-g and a vacuum.  People have built gizmos that depend on the
presence of air or friction to cause the appearance of a reactionless
drive, but these gizmos only work when sitting on tables.

The problem with a reactionless drive is that it would violate a lot of
principles that physicists are pretty attached to, like conservation of
momentum.  A lot of the specious reasoning used in the explanation of
so-called reactionless drives tends to ignore things like the momentum
of electromagnetic radiation or the finite speed of light.