On Mon, Mar 23, 2015 at 10:09:22AM -0400, Jeffrey Schwartz wrote:
> http://www.engadget.com/2015/03/23/boeing-plasma-shield/
>
> So, I'm wondering...
> Can one use a plasma rifle with computer targeting to counter-blast the
> wave front of really big explosions ?

The idea behind the patent there is not so much to prevent a shock
front from hitting, as to refract it so that the pressure increase
isn't one very sharp pulse of high pressure in a fraction of a
millisecond, but a mess of increases adding up to about the same
pressure over many milliseconds.  It doesn't reduce the energy at all
(actually adds to it slightly), but reduces the brisance ("shattering
capability").

The main effects of a really big explosion will all still be there.
Just one particular effect might be reduced.  So for the rifle idea,
almost certainly not, unless your rifle has a setting for "wide area
close range blast".  Even then, it would be of limited usefulness.  If
you do it wrong it could actually make things worse, by focussing and
intensifying the shock front instead.

- Tim