Fusion

Tim Day wrote that 4 H -> He doesn't work, i.e., that you must have D or T in
the reaction.  Since when is it graven in stone that ordinary Hydrogen doesn't
work in fusion?  After all, our Sun does it that way (if you dare to disagree
with me on that point, I would be more than happy to discuss stellar physics
with you).  I see no problem with extrapolating a future technology which
allows fusion of ordinary hydrogen through some heretofore unknown exotic
process.

This means that Mr. Day's interpretation of fuel refining as extraction of
heavy isotopes from lighter ones (of hydrogen, that is) is WRONG.  As I
understand fuel refining, the difference between refined and unrefined fuels is
that unrefined fuels contain hydrogen in combination with other atoms (i.e.,
the fuel contains methane and water and other shit in addition to pure H).
This seems to be echoed by other physics-minded refs I've spoken to.  Military
craft are often fitted to use unrefined fuels, and presumably can refuel at a
gas giant or on a water world -- and this fits the general scheme of things.

Robert P. Poole                       [email removed]
[address removed]                     MIT Course VIII
311B Bexley Hall                      "We make Idols of our concepts, but
[address removed]                      wisdom is born of wonder."
                                         -- St. Gregory the Illuminator