invisible man

[joshuam168]

i dont know how many of you ever saw that show called the invisible man, im talking about the new....if there there is an older one...? but the idea is that he contains an organ inside his body that secretes a substance called "quicksilver" over his body. now this refracts light in such a way that it makes so that human don't see him, i.e. invisibility. im not asking about the possibiity if have the organ, or to debate the name....i want to know if its scientifically possible for light to refracted in a way that would cause invisibility...and if so is it remotely within possibility of our current technological state?

[iNow]

Here are some neat references:

 

http://news.uns.purdue.edu/x/2007a/070402ShalaevCloaking.html

http://www.seas.rochester.edu/~gresh/math/math_113006.html

http://sciam.com/article.cfm?chanID=sa003&articleID=7BBE5A38-E7F2-99DF-31D7FBB0032C411C

http://news.bbc.co.uk/2/hi/science/nature/6064620.stm

[joshuam168]

oooh...thats kooool. i didnt know they could do that.....but is it possible to have a substance cover your body and refract it? refraction doesnt imply the same thing as does bending light correct?

[Klaynos]

Quick silver implies mercury.... and if you've ever seen anything covered in mirrors in a forrest you'll realise just how well just making something reflective works...

 

As for a substances that you could just paint or similar onto a surface or person to make them invisible. No.

 

We can make metamaterials that are "invisble" at a single wavelenth, but currently only for microwaves. Engineering such substances for broadband or visible are both very difficult and we are no where near to that at current.

[swansont]

refraction doesnt imply the same thing as does bending light correct?

 

Refraction is the bending of light due to a difference in index.

[Wormwood]

 

http://www.military.com/soldiertech/0,14632,Soldiertech_060518_camo,,00.html

[joshuam168]

Refraction is the bending of light due to a difference in index.

 

once again wording fails me...sorry. i meant refraction doesnt imply the bending of light completely around a body does it? i know refraction refers to a certain degree of bending....but does it refer to as high a degree as mentioned in the first link provided by Inow?

[w=f[z]]

Seems like to be invisible, the object in question must be 100% transparent. And then, I suppose it would have to be 100% transparent to all radiation. Oh yeah... and it mustn't emit any radiation.

 

Seems impossible off hand....

 

Cheers

[swansont]

once again wording fails me...sorry. i meant refraction doesnt imply the bending of light completely around a body does it? i know refraction refers to a certain degree of bending....but does it refer to as high a degree as mentioned in the first link provided by Inow?

 

That would depend on geometry. Bending around a certain path seems more of a waveguide effect, which is related (heck, it's optics, so it's all related)

 

"Natural materials typically have refractive indices greater than 1. The new design reduces a refractive index to values gradually varying from zero at the inner surface of the cloak, to 1 at the outer surface of the cloak, which is required to guide light around the cloaked object."

 

So they are able to make a gradient-index material with an index < 1 with this technique. That makes for an interesting waveguide, since your "cladding" material (that has the highest index) can be the air.

[Farsight]

i dont know how many of you ever saw that show called the invisible man, im talking about the new....if there there is an older one...? but the idea is that he contains an organ inside his body that secretes a substance called "quicksilver" over his body. now this refracts light in such a way that it makes so that human don't see him, i.e. invisibility. im not asking about the possibiity if have the organ, or to debate the name....i want to know if its scientifically possible for light to refracted in a way that would cause invisibility

 

No, it isn't. We have plenty of examples of light being refracted, and the result is not invisibility:

 

 

Thus your "quicksilver" man would look like a silvery glassy distorted outline of a human figure. Somewhat disconcerting, and if he remained motionless he might pass notice, but he wouldn't be invisible.

 

...and if so is it remotely within possibility of our current technological state?

 

No. One could make a person more difficult to see, but not invisible.

[Jacques]

http://www.sciencedaily.com/releases/2007/09/070905203843.htm

Theoriticaly possible for all wave length...

[Klaynos]

http://www.sciencedaily.com/releases/2007/09/070905203843.htm

Theoriticaly possible for all wave length...

 

2 things, does that say it's broad band? I have issues with popular science articles and these things, they are normally missguided.

 

and "made to ideal specifications could render an object" that probably means idealised epsilon, which, well good luck finding that!