One idea I had was that you might assemble an artificial molecule with a pair of ferromagnetic atoms either side of a large cavity like the inside of a buckyball. Maybe if you squinted a bit and didn't know enough about organic chemistry this would form an itsy bitsy eeny-teeny Penning trap, just big enough for a pair of positrons in opposite spins w.r.t. the fields of the ferromagnetic atoms. The thing ought to be stable so long as you don't distort it too much (shock) or break down the moleucule (flame, ionisation). When you did, the two positrons would escape, annihilating two electrons to produce four brutal gamma rays. These will be absorbed by the surrounding material, ionising, heating and compressing it and releasing positrons from adjacent molecules. In other words, it would be an explosive.Drooling Iguana wrote:You want a futuristic weapon? Have your civilization figure out how to miniaturise nuclear warheads to the point where you can fit one inside a 9mm round. Or perhaps invent some sort of super-efficient containment system that lets them fill a 9mm bullet with antimatter.
If we say very roughly that the molecule is about C(120)H(120)Fe(2) it would have a molecular weight of about 1672 AMU. Its disassembly would involve a 0.000 014% conversion of mass to heat and shock, or 13 GJ per kg. That isn't anything like the yield-for-mass of atomic weapons, but it is orders of magnitude better than chemical reactions, and it is scalable to much smaller charges than nukes are good for.
A bullet containing a gram of of that stuff would ruin somebody's day.
And then, when technology improves, you can put an anti-proton in place of the two electrons, for 8,500 times the yield. Bang!
And it might be useful as a high-specific-impulse rocket fuel.