In the darkness, Firenze could almost make out the bobbing heads. In a way, he felt a little guilty. He wasn't truly accurate with his descriptions, just 'true-enough' to get his points across. He'd imagine an actual n-matter expert would probably want to strangle him for this degree of simplification, but then again, how many physics classes started with the phrase, 'assume a uniform object'? Courteous lying was sometimes part of teaching.
Firenze explained, "Negative matter, in keeping with its inverse nature, behaves the opposite way. It releases energy as it gains negative mass, and then removes energy it as it negates."
"What?" A voice asked.
Firenze agreed, sympathetically, "I know! It's weird. As negative matter - let's call it n-matter - is formed, it releases energy as if an inverse amount of normal matter had been annihilated. Mass and energy are linked, but n-matter perverts the normal equivalence. This is why Bergman got ignored for so long. Now, after his work with Indra Singh, there was no denying that this stuff could exist, because it did, but it's still not something our monkey-brains want to deal with. If you make two kilograms of n-matter, you get a yield of energy - mostly heat and light - as if you'd just annihilated two equal kilograms of matter."
A voice he didn't know asked, "So, what's the issue? We've got reactors. We can do security."
"The problem is that this seems to violate thermodynamics. The laws of the universe say that you can't get free energy and mass. But don't worry, despite being weird, n-matter is also conscientious, so it resolves that paradox for us! At the risk of anthropomorphizing it-"
"What?" That northern-accented voice belonged to one of the engineers, Gerdoux.
Firenze defined his term, "Making it seem human."
"Okay. Go on."
"At the risk of making it seem human, maybe it knows that it's wrong for our universe, and tries to slide out the back door." Firenze half-joked, then explained, "Again, inverse. Normal matter decays, releasing radiation. N-matter 'negates' - it starts pulling in energy, and rapidly. It's highly reactive, massively endothermic. Everything around it gets drained: heat, light, electromagnetism, even bonds in ordinary matter get harvested for energy, and as the n-matter gains energy levels, it sheds mass, returns to equilibrium, and it removes all the 'extra' energy injected into the system at its creation. Think of it as a big pit that needs to be filled before it vanishes."
Firenze saw the heads bobbing in the darkness, caught in the neon flashes of the projector.
He continued, "So, yeah, it's hazardous. The theory is that in extreme situations at the edges of the universe, the negative matter is produced - but only as particles - which negate themselves against their surroundings, and never in enough mass to have a noticeable effect. Bergman provided a means to harness it in substantial terrestrial quantities - enough to lift vehicles, even cities. We're dealing with a substance that is ridiculously difficult to handle, which emits tons of energy when produced, and then tries to negate itself back into oblivion. It's completely unique and whole a lot of fun." For most people, that last statement might have been sarcasm, but most people weren't Grant Firenze.
Lieutenant Poole interjected, "So the Greens weren't kidding when they said my car was toxic?"
Firenze hadn't noticed any officers sneaking in. He tried to act natural, as if this didn't add any stress, and answered, "Correct, but not in the way most mean it. The Bergman drive produces an absolutely absurd amount of energy. Read that as 'heat' for most purposes, but there are some kinds of radiation that have to be shielded, hence the size of most lift casings. Remember, the n-mass is being used to lift the vehicle. Now, on something like a car, that's a small amount of energy from the sump, maybe equivalent to, I don't know, a rather large nuclear bomb."
Firenze heard the shocked whistle from that stinger, and he tipped his safety-cup over the projector in acknowledgment. He said, "Consider that, the next time you take it for a spin. You're harnessing a nuke to fly. Now scale up for something like the Plymouth, and the energy is somewhere closer to a not-insignificant fraction of solar output. That's world ending."
That got some whispers, including an indistinct, "That's insane!"
He explained, "It's not crazy, it's just... let's say you have to build for safety and take advantage of n-matter's natural properties. Remember how I said it negates itself? It absorbs energy from its environment? This can be harnessed. You start small, generate a few negative particles, then a few more. You let the newly-released energy of the new particles get absorbed by the very-slightly older ones as they negate. Each cycle, you make little more, until you've got atoms. Keep increasing the n-mass, slowly but surely, until you have a few micrograms. Then kilograms. Then tons. Now you're riding on the chariot of the gods. The occlusion cycle keeps the system stable, as energy gets poured out and sucked away.
"When it's time to lower down, you just dial it back, produce a little less n-mass than the last iteration. Slow is the key here. You make a little less each time until all you have left are the particles. There's a reason these engines take so long to spin up and down. Now, there's always waste, even in a precision juggling act like this. You know the huge radiators on any lift vehicle? Those are for the tiny, tiny fractions of stupendous heat being lost. The armored belts of variable density shielding materials? For the even smaller loss of cute little rays - like gamma. And the power plants, the giant fusion reactors on the airship? Those are to pump energy into a negative matter buildup, to give them something 'easy' to chew on."
There was a moment of quiet, until Rutman asked, "And we're going to break this thing? On purpose?"
"Well, fortunately, the systems
