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How To See Through an Invisibility Cloak
AMESN writes "Ways to bend light around objects and render them invisible are becoming a major field of scientific study and gaining ground. While no actual invisibility cloak exists yet, researchers are also theorizing on how to beat the perfect cloak."
The kind I want to go out with. WooHoo; particle launcher!
Great minds think alike; fools seldom differ.
turn it on?
How about a heartbeat sensor from Modern Warfare 2?
Games are a goldmine for these sorts of wacky ideas which just might work.
And instead of side of weapon, add that to the in-front-of-eye see-through monitor. Why we don't actually have such already? The technology is there. But even US army is testing with things that will actually take away the whole view from your other eye.
No invisibility cloak can hide the fact that it's still a solid object. That or utilize various frequencies of EM as it would be extremely difficult to defeat radar + infared + visible + UV all at the same time.
Sigs are too short to say anything truly profound so read the above post instead.
Just throw a stone at it.
> While no actual invisibility cloak exists yet, researchers are also theorizing on how to beat the perfect cloak."
How about flour and water? This reminds me of a joke...
They have invisibility cloaks now they are looking ways to beat the ones the others sides are useing.
In that scenario aren't you supplying the particle launcher yourself?
I see even classic Slashdot is now pretty much unusable on dial up anymore.
Why make things complicated? Just carpet bomb the region where you might have cloaked dudes running around. They won't stay invisible ;).
512 MB RAM, 20 GB disk, 200 GB transfer, five datacenters. $19.95/month.
And because cloaks that shield longer wavelengths of light are easier to make, first successes came with microwaves — whose radiation can be measured in inches.
Or RADAR?
It's NOT me! It's the meds! I'm on 1000mg of Fukitol.
Just toss my visibility cloak over the suspect and you will be able to see anyone under it.
If you can, it's not perfect.
The real problem isn't detecting it. It's knowing that you need to be trying to detect it in the first place, and approximately when and in what area.
I see even classic Slashdot is now pretty much unusable on dial up anymore.
A laser pointer, the cheap red kind you can find at any corner store.
Vadim Markel of UPenn has shown that negative index of refraction is inconsistant with the second law of thermodynamics:
http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-23-19152
At least that approach makes cloaking impossible. I am not sure why people are being so slow to accept this. Probably since so much funding has gone into negative index of refraction. Note there is also an arxiv paper on this.
But be aware of the tactical insertion perk. Sucks to get killed when you're going to check the place and get shot just because some fucker put his tactical insertion there to spawn again on the same camping spot.
Flamethrower.
Ala Marilyn Monroe in "The Seven Year Itch".
"There is more worth loving than we have strength to love." - Brian Jay Stanley
TFA mentions using charged particles and multiple wavelengths of EM to detect a clocked object. TFA suggests that they were measuring the actual effect on the path of the radiation its self although it should be pointed out that this is quite possibly unnecessary as high energy charged particle entering a solid material undergo an extremely high de-acceleration phase which causes charged particles to emit EM radiation. It's called Bremsstrahlung radiation and could quite possibly be detected.
Sigs are too short to say anything truly profound so read the above post instead.
If those particles are being launched at you, you might want to consider a different girl.
A perfect invisibility cloak is also a perfect blindness cloak. Unless you make i.e. missiles or bullets (dodge that, Neo!) with it, things with a predefined target, could be somewhat useless for most interesting uses. The imperfect are the useful ones.
1. If footprints appear on the ground but you cannot see anyone walking, then throw flour or paint at this spot.
2. Listen for the sound of an invisibility cloak scraping against the floor.
La Forge already discovered this when they did made a tachyon pulse grid to detect if there are any Romulan ship trying to get in to Klingon space while the there was civil unrest in Kronos.
Also, the Jem'Hadar was able to detect the Defiant while on cloak during their first encounter in the Gamma Quadrant by using an anti-proton scan.
An "invisibility cloak" these days doesn't just necessarily apply to the visible light spectrum. The cloak could be a thermal or radar "invisibility" cloak, leaving an object perfectly visible to the naked eye, but invisible on other scans. Penetrating thermal invisibility cloaks might end up more important, because camouflage can take care of visible light from overhead, it's the thermal that's the giveaway.
Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
Considering the amount of energy required to emit high energy particles and the short distance they can travel outside a vacuum, shooting electrons and reading the radiation would not be a feasible option. This is not even considering introducing large amounts of radiation to the area which you are scanning. How about a giant fan with a bunch of light weight objects and they will run into the invisibility cloak revealing its position. Either than or non ionizing EM waves...
Thanks, buddy. I suddenly feel much better about myself.
What about using mirror? I could imagine that working as a good weapon against invisibility cloaks....
You can drink a blessed potion of see invisible or eat an invisible stalker's corpse while invisible.
As long as we're talking about things that could never even come close to happening to anyone on this site, why bother with the invisibility cloak? You could just as easily jump out the bedroom window, land on your pegasus, which is floating just outside said window, and fly off to your Fortress of Solitude, which is totally not your parents' basement.
So, standard behaviour then?
Requiem for the American Dream
And you could use it to locate your invisible brain.
This technology is like all others - it won't stop an offended MicroSoftie from feeding the trolls.
It's always nice to notice there actually are a lot bigger nerds in the world than me.
I thought the article was about seeing the outside world from the invisible person's perspective. If visible light is beamed around you, that must mean you get no visible light for yourself, so the invisible man is also the blind man, no?
'cause cloak bends light and make it go a longer distance before reaching the sensor, and phase shift can be detected without a sweat.
Ah but it sure is funny when the guy is dumb enough to stand right next to/on top of his tac insertion, so after you kill him you can just camp there and get another easy kill =D
from TFA : "...but a cloak that perfectly hides objects at all wavelengths of radiation — including AM radio waves, visible light and X-rays — would be extremely difficult to create..."
How about ultrasonic sensors? Or rain, like another message says. Ground pressure or vibration.
I think something with enough sensitivity (like a cloaked object going past a stationary LIDAR gun beam) could see some disturbance that wasn't there before. If the light is bending around an object, it may be invisible but the light would be taking longer to make the trip.
A properly tuned laser beam frequency with matching receiver could probably detect cloaked objects too.
So much of this is by "cloaked to a person" and not to sensors.
Technically the tachyon grid was a trap. They purposely left a hole in the net to catch the Romulans. Of course, in the real world, a sensor array of even interplanetary scale is far beyond our capabilities. The sensitivity needs to be extraordinary to detect somethin the size of a ship at such distances.
Sigs are too short to say anything truly profound so read the above post instead.
I figure I could start research on how to overcome an NMP field, but I figure it really isn't my concern.
Are you being stupid intentionally, or were you just born that way?
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
This got modded informative? This???
Who the hell here doesn't have a set of D&D books?
</fake-nerd-rage>
It is invisible until it is found.
Ahhh, a proper response from a representative from the Pentagon. :)
It's also the same reason aliens will never visit us and say "hi". If you don't understand it (or can't see it), bomb it. :)
Serious? Seriousness is well above my pay grade.
nt
"Kill 'em all and let Root sort 'em out"
A handful of flour - good and covering just about everything within a 10 yard radius!
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
...only the blind shall see.
I'm sure widespread use invisibility cloaks will lead to increased recruitment of blind people to the military. And that blind kid who does echolocation will be recruited to train a new elite force of super-soldiers.
I think he just put on the wrong cloak.
If consumed, best digested with added seasoning to own preference.
A device designed to do one thing (bend light of certain wavelength) turns out cannot do another (bend other particle/wavelength). News at 11.
The only possible interpretation of any research whatever in the 'social sciences' is: some do, some don't
Thanks! Haven't had such a good laugh in slashdot for a while. =)
Everyone knows firing short, repeated bursts of tachyons between a 3 dimensional grid made up of Federation star ships is the most effective way to detect invisible, cloaked objects.
Fact: Everything I say is fiction.
This has always been something that's bothered me about Star Trek. It's well-established that "cloaked" objects, including people, still exist as solid matter and therefore displace whatever space they're occupying. I would think a foolproof means of tracking cloaked objects would simply be to concentrate on whatever it is they're displacing, and look for the telltale starship/person-shaped contour of gaps of nothingness where displacement is occurring. Take the interior decks of a Federation starship for example - authorized moving displacements signifying crew (tagged by their commbadges) if they simply ever thought to track the density and movement of the air they're pumping into each and every deck. Space is much the same way - it's not a perfect vacuum, and you can't tell me that Federation sensors aren't powerful enough to pick up damn near everything in their immediate surroundings.
This also bothered me in Stargate: Atlantis the multiple times Atlantis was cloaked to hide it from orbiting Wraith vessels. They know what Atlantis looks like, can't they just scan the ocean's surface and look for the telltale snowflake shape of water displaced by the city?
Point is: a cloaked object in a perfect vacuum (absence of everything) would be impossible to track using displacement, but a perfect vacuum exists only in hypothesis. Cloaked objects are always going to have to displace something, so rather than trying to pick up the cloaked object directly, why not concentrate on what you can see and look for gaps which shouldn't be there?
"There is much pleasure to be gained from useless knowledge." - Bertrand Russell.
You could just get a magical eye like Mad-Eye Moody....
I bet they turned on their prototype and lost it.
Hit it with something. Seriously, the obvious solution is to spam your environment with small projectiles, track them, see what bounces off something. Or blow on it it: tracking motion of air/turbulence as air movement in the environment is changed by the objects presence.
Point is if you have a object perfectly cloaked to a good swathe of the electromagnetic spectrum there are still other ways it impinges on it's environment. Accoustics, sound waves (although they may be easy to cloak also) etc.
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
Presumably, sensors that can penetrate cloaking would be very useful for the operators of the cloaked vehicle, because if no one can see you, you can't see anyone either. In order to see something, light has to be absorbed by the sensors inside the cloak. Since a cloak bends light around the vehicle, the vehicle is flying blind.
Not sure what the fuss is about--sonar should work fine.
We're getting a bit too excited here. If you read TFA you'll realize how limited this thing is. Many of these designs can only work at one frequency, usually microwave, in one direction, over a very small area, in 2D, and with considerable scattering and attenuation.
That's a heck of a long way from a usable cloaking device. The problems of scattering and attenuation are going to be particularly intractable.
It's unlikely that every one of the many shortcomings can each be improved by the needed factor of 100 or so.
Just use gas-seeking proton torpedoes to seek the emissions of the impulse drive.
Didn't they watch "Star Trek: The Undiscovered Country"?
Scotty [from Star Trek] already thought of this.
Everything releases "emissions" of some sort, be they EM Radiation, Gas, etc.
If the wearer is a person, just gotta look for some "emissions" ie: farts.
To quote Scotty, "it's gotta have a tail-pipe"
If the people who can see through your invisibility technology aren't the people you're warring with or hiding something from, then your invisibility solution doesn't need to be foolproof. A solution can be perfect for a given situation even if it's not academically or technically perfect.
Use a scrying spell, obviously.
I agree... this is definitely putting a proverbial cart before the proverbial horse^D^D^D^D^D unicorn
Evolution - Est. 4500000000 B.C. Don't piss in the gene pool.
This technology is like all others - it won't stop an offended MicroSoftie from feeding the trolls.
It also won't stop non-MS-fans who just think the comment was too dumb to even be used on SNL.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
I don't get it, microscopes can't see invisible things. And an invisible penis would be kinda cool, you could go to the beach naked.... though I worry what the cut off point would look like... I think it'd be a bit scary if people saw like the internal workings of my groin. Though you could use it to scare the shit out of people... I think it'd end up looking a lot like that censored jpns hentai with the invisible penises....
I get the feeling I gave this more thought than it was warranted.
What good would come from having an invisible brain? I mean I don't show off my brain in everyday life. Really, I'd be quite concerned for my health if anyone to see my brain.
I don't know, I've never seen one.
Sewage Treatment Facilities - "Our duty is clear."
Unlike pingpong balls, charged particles can move through an object, leaving telltale radiation in their wake.
They must not be doing it right.
I switch to infrared. Duh.
In C++, your friends can see your privates.
Scientists testing the technology to detect the 'perfect' invisibility cloak, have discovered that aliens do in fact actually walk among us...
How can you detect? put some yelling powder on the floor!
New Economic Perspectives
http://www.youtube.com/watch?v=JKPVQal851U/url and you know they have things better than what is shown on youtube. Which is probably why they are looking for something to see invisibility.
Doctors do Massage in Longview WA now, who knew?
Time of flight cameras such as the one in natal should be able to detect perfect cloaks due to the fact that light has to travel a longer distance, it would show up as a dent in the wall behind it.
Interferometry would also work as well by changing the interference patterns
- "There is nothing quite like an ineffective solution to an nonexistant problem"
Cloaking technology would be pretty damn cool...
... and lack thereof in the atmosphere around you away?
Just spray a firehose around the area, and watch the water bounce off the person or thing with the invisibility cloak? Obviously the water, unlike light, won't warp around the person or thing because it is matter and not photons.
I remember D&D scenarios trying to find an invisible person or thing:
#1 Look for footprints, spread some paint or dust around and let the person step in them and leave a trail.
#2 Throw water, dust, or paint around the room and eventually it will hit the invisible person.
#3 The person can still be detected by smell, using dogs or some other animal to sniff them out.
Remember, Slashdot does not have a -1 disagree moderation, and no, troll, flamebait, and overrated are not substitutes.
Well, the easiest way is to have Pyros that Spycheck, or just bump into the Spy by accident.
Wait, you don't mean in Team Fortress 2?
GLaDOS for President 2016! "Well here we are again. It's always such a pleasure." -- GLaDOS, 2011
Science Fiction has had the easy answer to this for a long time. Dirt, water, paint, anything solid or liquid that can spread out. I don't see how a particle beam can beat that. Why carry around a special weapon, when you can just get a firehose? Or pick up a handful of dirt? The main problem would be knowing that there's an invisible man in front of you.
The one case it might be useful is like a security camera, if you don't want invisible people sneaking into a building. But, the beam would have to be cheap enough to be on a LOT more often than necessary-an assassin could sneak in two days early.
I'm not sure what the name of that medical condition is, but it must be fucking fantastic.
Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
No, no, no! You have to nuke it from orbit--it's the only way to be sure.
Unity? Screw that: XFCE. Slashdot Beta? Screw that: SoylentNews. Australis? Screw that: Pale Moon. UX developers DIAF
Spray and pray in the direction from which an invisible enemy might approach. Where there's a blood spray, shoot some more.
Invisible this, bitch!
Warning: This signature may offend some viewers.
If they're going to be directing high volumes of charged particles at, say, a check point in some super secret facility, I pity the poor bastard in the cloak...
Evil Genius: "Muah ha ha! They'll never see me steal (insert object of power)! Now as I just slip past this gaurd booth and....ohh...ohh dear, my body body feels a bit tingly and..ohh GOOD GOD!! MY SKIN IS ON FIRE!!!!!"
Security Gaurd 1: "Huh? You say somethin Bob?"
Security Gaurd 2: "Nah. *sniff* You bring a bacon sandwich for lunch again?"
I thin it was Commander Data that did this.
I think he just donned the wrong cloak.
and wizard hat.
The actual hiding of a person or an object. I just wanted to point that out, in this respect, this is good news that technology is also being considered to thwart the cloak instead of just have a good invisibility cloak.
The reason I take it this way is... People are always asking, "who is watching the people who are watching us?"
Well after the "perfect" cloak comes out, this question becomes a lot more complicated. It makes me wonder if developing cloaking technology is even a good idea, if it is then who will watch the people(1) who are watching us(2) and watching the people(3) watching them(1) without themselves(1) being able to be fully watched?
Yeah... scary.
So let's see what the Slashdot community has come up so far...hmm, okay, use multiple EM frequencies at once or throw flour at it. Why am I the only one smart enough to know that using high frequency sound ways would work perfectly? Vibrations in the air will bounce off of solid objects regardless of any frequency of radiation cloaking technology. Just use one of those approximate distance sensing sonar thingies that use ultra high frequency and it'll say "Yep, there's an object there." I think they should stop inventing a cloak when a solid method of beating it already exists and can be built with current technology.
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
Technically the tachyon grid was a trap. They purposely left a hole in the net to catch the Romulans. Of course, in the real world, a sensor array of even interplanetary scale is far beyond our capabilities. The sensitivity needs to be extraordinary to detect somethin the size of a ship at such distances.
Wait wait wait, what do you mean "in the real world?"
"If this thing includes a microscope then the average Windows fanboy can use it to locate their invisible penises."
and
"And you could use it to locate your invisible brain."
Don't you just HATE it when the dentist starts drilling before the Novocaine takes effect? When he hits that freaking NERVE, you can't help responding - sometimes violently. I see someone got YOUR NERVE, LMAO
"Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
Strangely enough you can also detect pegasi by throwing rocks at them. True story.
Despite people named Baile Zhang and Bae-Ian Wu are involved they used the word "Chinks" in the article title?
Detecting the presense of an invisibility "cloak" is quite simple in theory. Not much harder for limited areas, but would be difficult for large areas or in highly mobile applications.
Simply put, it's a matter of timing.
If light is being guided around an object then it's taking a longer path than normal. Therefor the amount of time for the light to travel to an item behind the cloaked object would be longer than the time required if the cloak is not there.
As I said. Concept is quite simple.
For limited area's, for instance a hallway, an array of lasers in a frequency being cloaked (I'm guessing visible) would show the timing discrepancy easily.
For larger areas it would be more difficult on an engineering level. Mobile detectors would be even more complicated.
"I can't see you, but I know EXACTLY where you are!"
Ward
. Silence! Be thankful thy species is unpalatable! .
>>Other ways to defeat it? Talcum powder or other particulates (like rain ferinstance).
Yeah, in D&D we'd always carry sacks of flour around for invisible opponents.
It's nice to see that it has real world applicability.
Tag: Flour
Why the hell is the OP modded -1? Should be +5 Funny. If I had any mod points....
Squirters are the best girls, man.
// to do already: insert Jewish joke here
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Who says no actual invisibility cloak exists yet? Read "Into the Fringe," a 1992 book detailing the "alien" abduction accounts of Dr. Karla Turner and her family. Her son detailed one incident which involved what seems like just this sort of technology being used as part of an abduction event. Turner died (her closest friends and family believe she was murdered) by a suspicious fast-acting cancer in 1994. All relevant information is available free at KarlaTurner.org
Would a thermal sight work?
Should do the trick. Even if heat is bent around the target, you would see a pattern.
The question was how to see through an invisibility cloak based on the current research... essentially, bending various wavelengths of light/RF/EM around itself in some way. The "perfect" cloak would be the one to bend all such forms around itself.
So I'd use sonar... I'mn not using any electromagetic energy, but physical waves, not included in the "perfection" of the cloak. And we already know how to build ultrasonic imagers, so it doesn't even take new technology.
-Dave Haynie