We're getting closer, though—mainly through the use of "metamaterials" designed to reflect various wavelengths. Some of the most recent advances include:
- a "cloak" that masks distortions caused by hidden, cloaked objects, but only at the nanoscale and only from microwaves and infrared (though that's an advance in and of itself; mostly it's just microwaves or infrared). It's three-dimensional, though, so you couldn't peek behind the cloak and see anything.
- silver plated nano-particles in water*, which react to a magnetic field to essentially form a mirror
- a metamaterial** that makes objects impervious to low level magnetic fields
- another metamaterial*** that can make one object appear to be something else, by bending light
- a third material that not only makes something invisible, but also creates an illusion of something else (similar to the above)
- a fabric of tiny gold corkscrews, to bend light****
- a material that can be made to reflect/absorb different wavelengths, and which remembers configurations ****
Yeah, we're not there yet and maybe we never will be, but this advances still have some pretty good fictional potential. For instance, it could be possible to cover a vehicle, even one as big as a space freighter, with that cloak from my first bullet. It wouldn't work at close range, but if you were coming into a planetary system and using infrared to gauge how many enemy ships are there, you'd prefer they weren't using this technology. You'd also want to be using it yourself, so they didn't see you coming.
Being able to make certain objects impervious to magnetic waves could mean new kinds of experiments and new electromagnetic engines, and could even be used for educational toys.
The suspended nanoparticles could fill walls or smaller objects, to hide what was inside. However, you'd need a way of blocking foreign signals, or the invisibility wouldn't work so well—and there'd be all kinds of hijinks involved after someone uses the wrong frequency on the device.
Creating illusions would lend itself well to pranks, of course, but would also supplement holographic media. Imagine a holodeck containing Wii-like objects that "morphed" into whatever the game or simulation demanded. A simple rod could become a gun, a sword, a cane, or an oar, for example. Alternatively, you could create the illusion of having more weapons, more people, bigger weapons, bigger people, or use illusions to lure thieves.
And then, of course, there are the armour possibilities, but those are so obvious I'm going to gloss over them.
Anyone else have ideas?