[sub]THE ABOVE LINK WAS COPYWRITTED W/OUT EXPRESSED WRITTEN CONSENT AND TOTALLY PLAGERIZED FROM AN OUTSIDE SOURCE. THE OPINIONS ARE THAT TOTALLY OF THE AUTHOR AND NOT NECESSARILY OF THE SDMB, THE CHICAGO READER AND/OR ITS MEMBERS, ESPECIALLY ME[/sub]
A Google search turned up this page from the University of Texas at Austin about transparent skin, with pictures: http://www.ece.utexas.edu/bell/xprojects/tissueOptProp/main.htm
And the first person to ask how you can take pictures of transparent skin gets experimented upon.
To the OP: I recall reading somewhere (I believe it was in a book titled The Flying Circus of Physics) that invisibility would work if you could find a way to give the retinas an imaginary index of refraction. Good luck.
That link has nothing to do with temperatures lower than absolute zero. At absolute zero, as pointed out before, all motion, including spin, stops.
Peeweee’s posts have little to do with actual facts. Many of his errors have already been pointed out, especially by glee. One that hasn’t is that carbon dating is very accurate. The problem with it is that it can only date so far back, perhaps 3 or 4 thousand years, if that far. That’s why radioactive dating is needed for older material.
Also, as not pointed out before, there is only one phenomenon known as a black hole, but the size of this hole can vary tremendously. (The “size” referring to the area within which light is trapped and not the singularity itself.)
As bup pointed out, peewee has no idea what a supernova is, and since this thread is not about astronomical phenomenon I am not going to edify him here.
[hijack to end the hijack]
There is a meaning to negative temperature, of sorts. It’s just that the temperature scale starts at 0, goes up to infinity, becomes negative infinity, and then moves up to approach zero from the right. But it’s mostly a mathematical construct.
At absolute zero, motion only stops if you ignore quantum mechanics; there’s another thread around here today discussing this which I am to lazy to link to.
There are multiple types of black holes. The basic ones have only mass, but you can add electric charge and angular momentum (and also magnetic charge, if that exists), and it will change the nature of the black hole.
[/hijack]
I don’t see why it’s not possible in principle to make something invisble to certain portions of the spectrum (say, visible light), but I don’t see how you could ever hope to make anything invisible to all light. I suppose you could put on an invisibility suit of some sort like that described here, but I agree with Mangetout that it probably would never be able to make you completely invisible. I mean, suppose someone shines light at you from the front. It hits you in the chest and now has to be routed around your body and emitted from your back, so there’s some extra time delay with that, right? So couldn’t you just make a sensor that’s sensitive enough to notice this (really really tiny) effect? (The eye, I suspect, would never know, but…)
Fnord, fnord, fnord.
See, it works! Most of you unenlightened readers are now wondering why there is a blank space above this paragraph, aren’t you. Mwhahaha.
This is getting more into the philosophy of technology than the OP per se, and I don’t want to be snide, but your inability to imagine a solution probably will not constrain the rest of humanity. Alexander Graham Bell was a smart dude, but he could not have conceived of a Cisco router, much less a modern switching station.
It’s very practical to look at what can be done today, with given resources and technology, to solve a problem or say that it cannot be solved at this point, but to say that something will never happen is foolish. You and I are simply not equipped to conceive of what will be possible in a hundred years, and the technical details of this project may be commonplace by then. That doesn’t help Superdude much, but I think his “physically possible” question can be answered if you permit a little what-if.
I think it was Arthur C. Clarke who said something like “If an old and venerated scientist says something can be done they are almost always right, but if they say it cannot they are very often proven wrong.”
micco: Any sufficiently advanced technology may be indistinguishable from magic, but the converse does not logically follow. Any form of magic need not be achievable by sufficiently advanced technology. Just because we think that (say) a FTL drive would be really, really cool doesn’t mean Mother Nature will let us have one.
Believing that everything must be possible is a modern form of superstition. It’s based on faith, not science.
Nice strawman. You’ve twisted my words just enough to refute them.
I never said everything must be possible. I was discussing a particular device which another poster said was impossible and would never be possible. I believe his impossibilities are mere technical difficulties which could be worked out.
I never said that everything was possible. I simply wanted to point out that predicting that something would never be possible is often foolish. The same has been said of planes, trains, and automobiles. Practically every technological advance was solemnly proclaimed to be impossible at some point. Luckily, creative people keep open minds.
I’ll return you to your regularly scheduled thread and let you have the last word, as long as you don’t twist mine again.
Let’s get back to the OP, now strap yourselves in for some wild ass speculation.
We have all seen how heated air can bend light. We have also seen how stage magicians can make themselves “invisible”. Now imagine a device that can excite the air around it creating a “bubble” of excited/ heated/ ionized air, creating a system of lenses that would difract light around the device. Not too different from Predator, which was mentioned earlier
It really wouldn’t be much different in principle to what stage magicians do. The key difference is that the device would be using lenses made of the surounding air instead of mirrors. A suit wouldn’t be necesary because the user of the device would be inside the bubble.
As to the problem of how the user could see out, I can think of two solutions. The first is a two way mirror effect. I am not sure sure how this would work in the system described, but hey, this is speculation. The second would be goggles that read light of a different wavelength, like infrared.
Might work.
When you finished building them, I’ll take one. I’ve always wanted a heated bubble of invisibility with 2-way capability.
DaLovin’ Dj
micco: I’m still waiting to hear where I can buy a flying carpet and a lightning wand. Maybe you could recommend a catalog?
Anybody hear about the new cammies the Marines were just issued? They are custom fitted to each individual.
Supposedly a Predator type of camouflage.
jimpatro, do you have any more information on these things. I thought the were more akin to “gillie” suits than to anything even remotely high tech.
Sorry, only sketchy details(oxymoron?). I caught it on a network news story. The only thing else I remember is that no one was being allowed to see or photograph them.
Maybe it wasn’t that the weren’t allowed to, maybe it was because they **couldn’t…[sub]ooooooh.
SAW that one coming.