Prophet710 wrote:

it creates a field around it when charged that dramatically reduces the mass constant allowing the "bubble" to be accelerated using less energy.

First things first: it doesn't reduce mass, it reduces inertia. Otherwise you would need to explain where the mass-energy went, which is troublesome. Generally, trying to explain magical physics is risky, since your explanation could open enormous loopholes. It is better to have a somewhat plausible sounding technobabble or even "nobody understands it" - less risk of the players coming up with a method of blowing up stars with it. My approach is to start with physics related to the issue, look up a bit of theory, and then spin a handwavey "explanation" that it is related to some aspect of it. So, how would I "explain" an inertia damper? Well, there are several physical theories about the origin of inertia, and we are in luck - there is no agreement on which is true, if any. Perhaps the coolest thing would be that the effect is related to Mach's principle: inertia is due to all the other mass in the universe, affecting the local objects through something like the Lense-Thirring effect. So the material just shields the nearby objects by some field that reduces this effect. Now, this might be enough, but we could spin this a bit further. Checking the LT effect you see that it relates to rapidly spinning objects like black holes. Now, what if the material was partially *made* of quantum black holes? This is not as crazy as it sounds, since there are theories about quantum black holes that could sit stably inside atoms - or, if they are charged, act as atomic nuclei. Now imagine that the material is just a lot of lightweight spinning black holes, and by charging it up or putting it in a magnetic field you change their rotation. Handwave, handwave, and this produces a counter-field that reduces the Mach effect inertia. "Dr Zhang, you are telling me the stuff contains black holes?!" "No, it is almost completely black holes. Just a sprinkling of electrons to keep it neutral. The rest is a lattice of black holes held in place by what I think is an analogue of ferromagnetism, but using Hawking radiation." "I have no idea what that is." "Fine, that makes two of us. I can only tell me what my sensors and AIs tell me. The really weird part is how the angular momentum - which is incidentally why you cannot turn blocks of the stuff around - interacts with electromagnetic fields..." Another take on what inertia is, is that it is due to interaction with vaccuum fluctuations of the quantum fields. Particles are surrounded by clouds of virtual particles that affect their motion. So the material affects vacuum structure, perhaps by something like the Casimir effect, and this is enough to reduce inertia. "My dear Leaping Hydrogen Salmon, this material is a natural resonator. It is not just organized on the nanoscale, I think there are elements of gluonic strings that turn it into something like an optical crystal on the femtoscale. Except that this crystal changes the background quantum fields when you tune the lattice size. Allow me to demonstrate..." A third take on it is that the material is actually a hack, and reality is simulated on a computer. What is truly going on is something like a cheat code. This means that the material might allow you to do all sorts of magical things... and have a trans-cosmic GM, virus killer or operating system stamp you out when it catches you. "OK, the composition is utterly normal: it is ytterbium deuteride with some small inclusions of gadolinium. There is nothing chemical or physical that can explain the effect. However, I think the secret lies in the inclusions: see how they form a Thue-Morse sequence? To me, it suggests a *computational* meaning. The material is some kind of code..." A fourth take: normal matter is full of bound dark matter, and is actually lighter than one would think. The material can emit a force on the dark matter that repels it, turning nearby matter light. When you turn it off, the matter returns to normal quickly by absorbing ambient matter. "Ladies, gentlemen and gentlethings, I think I got it: neutralinos. The material is composed of stable superheavy elements with toroidal nuclei that are just the right size and mass to resonate with the super-symmetry field. When you do *this* you create a field gradient, and the neutralinos bound to your atoms slip away. There is no need to thank me, I will wait for my Nobel Prize in humble contemplation when we get home." Note that a real inertial reducer would have nasty effects on a lot of things. A normal heart contraction would make your blood move much faster, and indeed sounds and almost everything would speed up a lot. I suspect the melting and boiling points of materials would go down. And so on. Best not to think about it.