"terrifying yet unambiguously newsworthy apocalypse incident"
Chinese scientists have stunned the world of boffinry by fashioning an artificial "black hole" generator out of copper-coated circuit boards. Disappointingly this is not a black hole in the normal sense of a universe-wrackingly dense lump of hypercompressed matter, exerting a gravitational pull so fearsome that not even light …
Sounds like this would make good radiation sheilding for a trip to mars.
As the size of the features which do the absorbing will be realted tot he wavelength of the incident photons, and the dangerous space radiation kind have energies many orders of magnitude higher than microwaves, thus wavelengths smaller than these features can be made.
Another big danger in space is the cosmic rays, charged particles that can do a hell of a lot more damage to tissue than microwaves. It sounds like the EM this would stop could also be blocked by cheaper/lighter shielding.
I'm sure this stuff will have many interesting applications but whether any will be practical is unknown. Still cool
Sounds fascinating, but 'microwave' covers a pretty broad chunk of electromagnetic spectrum. Would be interested to know over what band of frequencies this device works efficiently.
Just need to point out that not all us know what a 'metamaterial' is, tho copper doesn't seem to fit the Star Trek connotations. Does this meta-ness confer the healing properties associated with copper wrist bands in the Pagan mind for instance? Someone help me out here?
The wikifiddlers have this one covered:
See how easy enlightenment can be?
...and fools seldom differ.
Can you stick one of these in your car and not trigger a speed camera?
But why stop there? I intend to put mine on the roof of my house so I don't have to pay council tax!
I even took it with me to McDonald's where they said I could eat for free.
When I first got it from china, I was made out of wood and string, now I'm a real boy!
driving below the speed limit will.
"Possible visual-spectrum successors would appear as a black blob to the human eye rather than being invisible."
I believe a coating with similar properties used to be popular for manufacturing wall-mounted writing surfaces once used in school classrooms. Its stealth properties could be modified by the application of calcium carbonate pressed into stick form.
Crank up the power of the radar emitter and burn the suckers, that's what I would say.
Then hit them with a Sidewinder or other heat tracker!
"It also seems worth noting that a device able to convert visible light into heat with high efficiency might seriously improve the performance of solar power apparatus."
What, you mean like black paint?
except black paint would absorb the light across it's entire surface which means the heat at any given point isn't going to be that much higher than ambient temperature.
This device would take all the light hitting the surface, and delivery to a small point in the center where it is converted to heat. It's the same amount energy as the black paint object, but the temperature gradient with the ambient temperature would be higher and so useful for doing work , such as with a Stirling Engine.
So lots of mirrors and a tiny spec of black paint then? See the "power tower" on wikipedia:
but without the gurt big tower and frangible mirrors
«except black paint would absorb the light across it's entire surface which means the heat at any given point isn't going to be that much higher than ambient temperature.»
On a sunny days you can boil water using only black paint and insulation. Very simple really. Take a clear glass bottle, paint half of it in black (along the height), lay it in a box of sand, half-burried, black half at the bottom. Cover with a glass plate, place in the sun a 3 pm, your water will be ready for the proverbial 5 o'clock.
I tried it back in the days of my innocent youth. Naver made any tea that way though, for 2 reasons. I was too young to drink tea, and I never found a bottle that didn't burst open under the pressure. Even the cider bottle caps popped, and these can take a lot of pressure. Back then sandy tea was not desirable. Nowadays, given the carbon-conscious fashion, you could maybe get people to actually drink it if you emphasize the "green" side enough.
... that a black hole genuinely exists, until such time as I can see it with my own eyes.
a Playmobil re-construction then?
We have them already, shirley? - otherwise known as walls or cunningly fasioned fabrics (or cloaks) designed to absorb light, no?
I'll get my visual-spectrum successor.
USS Eldridge, 1943?
No the USS Eldridge was testing Degaussing to stop magnetic mines
Should work on Gatso cameras if I covered my car in it....
Make a cloak out of it and it'll help when the husband gets home and i'm sneaking through the back garden, yes he'll see a black blob running across the garden but it sure beats a naked man.
Or bum off of the nearest FM tower or something. This is 99% efficiency, man.
A spy plane that absorbs all microwave radiation and converts it to heat might get a little problematic :)
Unless, of course, the vehicle used some of that energy for propulsion, internal power (to compensate for smaller batteries), stored chemically for weapons systems, etc.
If you have a high enough differential, there's all sorts of uses for excess heat energy. ;)
Paris, because she knows all about generating focused heat to an internal core.
This would, in fact, most likely be worse than nothing for radiation shielding against solar and cosmic radiation.
Why? Because most of that is not in the form of photons, but in the form of really fast moving charged particles. Which have the highly annoying tendency of producing hard X-rays when they impact on anything metal.
The best way to stop them is something with lots of hydrogen in it, like water, certain plastics and ceramics.
The worst way to stop them is anything metallic.
So fast-moving charged particles strike a metal surface (which is tuned to absorb the EM range associated with hard X-rays), and produce hard X-rays, all the incident ones of which are absorbed by the surface and converted to heat, which is then likely to be emitted as IR.
Don't see the issue myself, you could use one as interplanetary shielding without too much faffing about, as long as the sizing for X-ray absorbers doesn't cause it's own problems :)
in a terrifying yet unambiguously newsworthy apocalypse incident
in a terrifying yet unambiguously newsworthy apocalyptic incident
This won't happen anyway as everyone who has an education will be privy to the fact that the world will end in December 2012. Which is also the reason I don't understand everyone getting so upset and over excited about the cost of the Olympics. The world will not be around so the cost won't matter.
IS the end of the world?
Another fiction becoming reality?
So we have a meta-material substance that absorbs all light ground into a fine power.
Anyway this substance already exists, its called black photocopier toner.
"Another fiction becoming reality?" ... Anonymous Coward Posted Thursday 3rd June 2010 13:36 GMT
That got me thinking further, AC.
If there were no words printed, would reality be totally different, ..... ergo is reality scripted for thoughts to follow and create/reverse engineer what is in essence and physicality/actuality, Virtual Reality, ....... for take away everything artificial/man-made/machine built, and one is as naked as a JBird in a Natural Paradise ..... Perfumed Garden of Eden, and one can then build everything again with Beta Imaginanation Shared in Words.
For a Second Chance ..... Knowing what's Coming.
I'm a little concerned that any radar-guided shed-seeking missiles might have a heat-seeker backup. Now the thermal signature of my kettle should be quite hard to lock onto, but once the targetting radar has started heating up my shed's copper coating - then I'm going to stand out like a sore thumb on infra-red...
Can a bonfire be used as some sort of missile decoy?
Visual camouflage is the least of one's worries. All you have to do is not mow the lawn for a few years, and the shed will magically disappear.
Obviously an underground volcano would be better, but a grass-covered stealth-shed is surely the next best thing.
Surely with all this heat generated (including from ambient microwave radiation we are bombarded with all the time) this heat might be stored for just such an occasion?
Most missile systems (the missile itself, usually) don't do well when bombarded with concentrated IR radiation, and at a certain point and beyond you burn out the detector. ;)
...or did an expensive circuit just go "fphhhut!" and they needed a really good excuse to explain why?
Microwave-absorbing materials may do wonders against active radar installations (since they lose their return signals, but isn't there increasing research into the realm of multistatic passive radars that work by tracking occlusion (and thus would cause radar-absorbing craft like stealth planes to stick out on the imagers like...like black holes)?
Black just got blacker. Can I get a leather jacket that does this?
the darkest optical thing I ever saw was the batch hydrising furnace for surface modification , pre-final sharpening of about a billion razor blades. The blades were vertically & horizontally stacked sharp edge pointing outwards and had a very low albedo. This system was being built in Hope in the wilds of Derbyshire.
This is obviously a perfect, cheap, all weather conditions heating element. Even in the worst weather (cloudy, rainy, etc.) infrared radiation still exists in abundance and so one of these absorbing energy and then pumping it into a house could be a very cheap way to heat the house with no reliance on fossil fuels.
Obviously depends on size, heat output, scalability, etc, but why go all complex with radar invisbility when theres a simple problem that this could be the solution too. Plus being a "green" technology, its sure to get billions in government funds to pursue...
lol. Especially in virtual apposition to the no longer detectable church on the hill.
when I was young and the world was new, we used microwave lenses as parts of antenna systems. Some of these used large chunks of dielectric material (perspex was a good one at the time) shaped like a lens to focus a plane wave onto a point (usually a small horn). Others used a number of anular metal plates of different lengths to focus a plane wave to a point. Antennas like this could also be used as passive repeaters. It is always a good idea with things like this to ensure a good match between the system and free space so as to capture the max amount of energy. Used at 2GHz, these things stood out like a sore thumb at light frequencies but, at 2GHz, would look like a black hole.
There is nothing new about the basic idea here. The main change is that as the frequency increases, things get a bit smaller. Bandwidth of things like this is a bit of a problem, but then, designing anything to work from DC to light is not simple.
...the description in the article, the word "antenna" immediately popped into my coffee-logged brain.
I guess you had the same flash, Stewart. Thanks for your post. While the mentioned device may demonstrate advanced engineering, it is hardly an invention.
It's just acting as an omni direction antenna with a gain of -0.04dB with a resistive load on the output. The gain figure's pretty good, 0dB being the theoretical maximum for a truly omni directional antenna. If it could be turned in to a small enough design working at about 900MHz then it would be a pretty good antenna for mobile phones, but looking at the paper it would seem to be too large for that.
So then, invisible to everything unless you look at the infrared.
Exactly how long can this shed stealther run before the shed's occupants are incinerated?
Can't we simply cover aircraft with frozen chickens to make them invisible?
Every time I stick a frozen chicken in my microwave oven it absorbs the microwaves which then get converted into heat and the chicken cooks from the inside. Sounds similar to this metamaterial stuff
Seems to me that frozen chickens would be an alternative to all this hi-tech malarky of creating black holes.
Sticking frozen chickens on the outside of bombers will also have the added benefit of having a meal ready for the pilots when they get back from their mission. In fact I think we could go the whole way and have a complete 3 course meal attached to the outside.
Since this is truly true, I hope this means I will have a cold fusion (which is true too) home power generator soon. ha
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