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Scientists Make Item Invisible to Microwaves
Vicissidude writes "A team of American and British researchers has made a cloak of invisibility. In their experiment the scientists used microwaves to try and detect a copper cylinder. Like light and radar waves, microwaves bounce off objects making them visible and creating a shadow, though it has to be detected with instruments. If you can hide something from microwaves, you can hide it from radar and visible light. In effect the device, made of metamaterials — engineered mixtures of metal and circuit board materials, which could include ceramic, Teflon or fiber composite materials — channels the microwaves around the object being hidden. When water flows around a rock, co-author David R. Smith explained, the water recombines after it passes the rock and people looking at the water downstream would never know it had passed a rock. The first working cloak was in only two dimensions and did cast a small shadow, Smith acknowledged. The next step is to go for three dimensions and to eliminate any shadow."
..from my ass, so to speak, but I imagine you could leave certain frequencies uncloaked, enough to slip in, say, remote video from a drone flying nearby or surveillance cameras in the area or GPS satellites in the case of bots. Perhaps a super-advanced version could shift cloaked frequencies on the fly in order to prevent jamming/detection of the video source even. I dunno, if this works in the first place it seems like there should be ways around the "blindness."
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This was already addressed to some degree in the SciFi book "The Last Mortal Man". The reasoning for making them illegal was that the criminal element used them to evade law enforcement. I'm sure the DHS would have alot to say about this.
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
I'll go out on a limb on a series of "ifs" (and maybe a bag of physics naivetes), but let's say we perfect this manner of imperceptibly "derefracting" light. And let's say we also complete the ambitious work identifying and manipulating gravitons, still hypothetical. Could we "cloak" spaces and matter from any interaction with our universe, not just electromagnetic? Maybe the Stong and Weak Forces would remain for interaction, but practically, outside the tiny diameter of a nucleus, could anyone notice?
Could a "gravity cloak" create subspaces operating as independent universes? Could we contain matter too highly interactive for current use safely? Like a tiny black hole conveniently near a device it's powering, or a pair coupled into a wormhole for "faster than light" travel through custom-folded space? Vast amounts of stuff crammed into pocketsized spaces.
Maybe the old playground philosphers choosing between "teleportation or invisibility superpowers" will finally have a lab to figure out which is really better.
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make install -not war
Yes, I know - this won't do that much against baryonic radiation, but for e/m . . .
If you bend the lightwaves around yourself so that they can continue moving past you, what light waves can enter your eyes, exactly? You'd be in pitch darkness, unable to see a damn thing because the light can't get to you because it's being bent around you. If you choose to allow some light through so you can see, then other people would see blackness there because there's light that's not getting reflected by anything... again, useless.
File under 'M' for 'Manic ranting'
Can you say boost and split? No reason why the light can't be routed and diverted.
Point. Let me clarify. Mathematically, they are the same thing. The principle of least action applies in both cases, just the path the minimizes the particular Lagrangian (T - V) (or Hamiltonian (T + V), if you prefer) differs depending on the potential energy. (Both methods are applications of the Calculus of Variations. ) Either way, it is a minimization problem and the same techniques apply. So, as far as I'm concerned, they tend to blend together.