I will probably damage my reputation by saying that I enjoyed last year’s top-grossing movie Avatar on many levels. Even the science, while highly popularised, did not contravene too many known laws of physics and facts of biology. Except for one thing, and that one thing has bugged me ever since. In hindsight, it’s quite amazing how long I allow stupid trivialities to bug me.
Anyway, Unobtainium.
I mean, seriously? Which script editor worth their salt would leave such an obvious ersatz-name in the finished product? What on Earth were they thinking?
As writers do when the going gets tough, I googled it. Apparently, Unobtainium, also spelled Unobtanium, is jokingly referred to in engineering when there is a need for a material that doesn’t (yet) exist. The term is also used to indicate materials that are extremely rare. In the movie, it’s a MacGuffin. What it does is not important. Only that it is rare and very valuable and thus is the reason for the hero’s quest.
Fine by me. I just wish they called it something else.
But it keeps nagging. There is that scene in the movie, you know, where the evil and hapless company director whose name I’ve already forgotten, picks up the sample that floats above a hollow dish. It makes me wonder what this stuff is. It looks metallic, and it floats. By what mechanism and what would people do with it?
First up, why does it float? It seems to me that it needs the dish to stay up in the air. That would suggest a magnetic field. Aside from the fact that I’m unsure that a bowl-shaped dish would emit the right shape magnetic field to keep an object afloat (I’m thinking it would need to be horseshoe-shaped), I’m wondering what the benefits of such material would be. Given a magnetic field strong enough, many materials could be made to float. Maglev trains work on this principle. The floating capacity would depend on the density of the material, the size of the sample and the strength of the field, and two of these can be varied by the observer. Creating a stronger magnetic field just requires more electricity, negating the value of the material. The repelling force that holds the sample in the air can only be as strong as that induced by the magnetic field, so to stay up, the sample must be very light. It could be a very light-weight, strong material. OK, but is that really valuable enough to raze an entire planet?
Secondly, it could be some sort of anti-gravity material. I’ve thought about how this could work, but am drawing blanks. If, for example, the material consisted of atoms of negative matter, each of these atoms would repel each other (as opposed to attracting each other, which is what regular atoms do), and the material wouldn’t stay together in a clump (hint: this is why we haven’t found any negative matter). But let’s suppose some sort of property existed that rendered the material inert to gravity.
Fine, but why stop at gravity? It’s nothing but a force (actually, it’s an acceleration, but let’s not get too technical). A material cannot know if a force applied to it is the result of gravity or something else. Would this type of Unobtainium resist being pushed or picked up? Ah, but it would only be moved if physically in contact with the object doing the pushing or pulling.
Fine. We have just established that Unobtainium would be an excellent material for making heavy lift, single stage to orbit space ships. Stuff that negates gravity. Woo-hoo!
Except now we’re in orbit. How do we come down in a space ship that wants to go the other way? Er…?
So what about you? What do you think would make an element exceedingly valuable?
P.S. I’m sure there is a short story in some of this. Somewhere.