On Tue, Jul 07, 2015 at 09:55:36PM -0400, Kurt Feltenberger wrote:
> What would happen if the intent was to turn it into plasma and then
> use a series of gravity planes (i.e. a "gravitic barrel" if you
> will) to focus and aim it?  Would it theoretically have a much
> greater range (and the longer the range the less damage it would
> do)?

The problem with plasmas compared with solid projectiles is what
happens in the kilometres past the end of the containment (whether
barrel or gravitic focussing).  Plasmas tend to expand extremely
rapidly due to their extreme internal pressures, while solids don't.

A solid projectile in space has a theoretically unlimited range
throughout which it does maximum damage.  The combat effective range
is limited by the target's ability to avoid being hit.

A burst of plasma will generally expand (explode) within milliseconds.
Its range will be determined by how far it can travel in those
milliseconds, before expanding to a uselessly sparse density.

However, this could possibly be extended by technology.  Plasmas are
affected by electromagnetic fields, so in theory it might be possible
to set up electrical currents within the plasma at the time of firing
to confine it in two dimensions while driving it to expand more
rapidly in the third (field laws prevent all three at once).  Unlike
gravitic fields, it's self-sustaining to some degree.  That's still
unstable, but it might last long enough to get some short but useful
range with much more advanced technology than we have.  I don't know
about seconds though -- that's an enormous timescale for dense
plasmas.

- Tim