Thread: Invisibility

  1. #1
    ¡Amo fútbol!
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    Invisibility

    How realistic is this? Basically, if a material were able to absorb all light waves at it, it would be a big black whatever, kind of like how stealth planes absorb radar waves. However, if it were able to emit light waves similar to the area around it, it would be invisible. Is this possible?

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    Just one more wrong move. -KEN-'s Avatar
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    ::coughs:: The philadelphia project. The truth is out there...!!!

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    TransparentMember correlcj's Avatar
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    Re: Invisibility

    Originally posted by golfinguy4
    How realistic is this? Basically, if a material were able to absorb all light waves at it, it would be a big black whatever, kind of like how stealth planes absorb radar waves. However, if it were able to emit light waves similar to the area around it, it would be invisible. Is this possible?
    The government has that type of nanotechnolgy...they are called chamelon suits. They built that type of suit technology after the movie predator, which was a great movie BTW. i dont completely understand if it emits, refracts and bends light in anyway but the technogy is real. They keep that like Operation Hush! Hush! But cool huh? BTW, whats your fav futbol team?
    "Be formless, shapeless, like water... You put water into a cup, it becomes the cup, you put water into a bottle, it becomes the bottle, you put it in a teapot, it becomes the teapot... Now water can flow, or it can crash, be water my friend."
    -Bruce Lee

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    Banal internet user
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    yes, I heard of this too... they've tested it in counter-terrorism scenarios so that a group of people can sneak up on a compound without being seen... from what I saw it wasn't perfect, but it made them VERY hard to see!

  5. #5
    ¡Amo fútbol!
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    Re: Re: Invisibility

    Originally posted by correlcj
    BTW, whats your fav futbol team?
    For the MLS, the Revolution.
    National teams: USA
    Euro League Teams: Real Madrid (they are definately stacked and fun to watch, especially since Ronaldo signed)

    I wish I could see more Euro league games. They are so much better than MLS. The only problem is you have to get special cable packages in the US to even get a few of them.

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    Refugee face_master's Avatar
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    ::coughs:: The philadelphia project. The truth is out there...!!!

    ::Gets dragged off::
    Cool, someone else knows about this. Is a really cool story. Its in one of my conspiracy books. Here's some info


    :: Gets dragged off ::

  7. #7
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    Did you read about the bank robber in Iran (no kidding true story, Iread it on www.abc.com.au under news)

    He was sold some 'spells' to make himself invisible. Pinned them on his arms and went into a bank and took money out of peoples hands.

    Was overpowered quickly.

    The police are now looking for the 'sorcerer' who sold him the 'spells'.




    Any body want to buy a used stealth suit?
    "Man alone suffers so excruciatingly in the world that he was compelled to invent laughter."
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    It's full of stars adrianxw's Avatar
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    >>>
    However, if it were able to emit light waves similar to the area around it, it would be invisible.
    <<<

    Such a scheme could only work if either the viewing angle was fixed, or the background against which the object was present was an unbroken solid colour which could be matched.

    In general, their have been schemes to render objects less visible. I remember seeing a demonstration whereby a tank was covered in electric light bulbs. When upon the ridge of a hill or similar, the light emitted tended to make the tank disappear into the sky, however, as soon as it was viewed against the ground, it looked, of course, like a ridiculous christmas tree.
    Wave upon wave of demented avengers march cheerfully out of obscurity unto the dream.

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    I saw a news post on /. about MIT being paid to research a new project for the US Military: biosuits for soldiers. The article stated that the aim of the project was to make footmen run faster and longer and jump higher and farther etc, and it could also bend light around it, rendering it nearly invisible

    http://slashdot.org/article.pl?sid=0...thread&tid=126

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    Registered User hk_mp5kpdw's Avatar
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    An excerpt of something I found that relates to this topic and is something I remembered hearing about years ago:

    There was a secret stealth design placed on the anti-submarine aircraft or World War 2. These aircraft would search for submarines by flying patterns at low levels over sectors of the ocean, the enemy sub lookouts would be able to see the airplanes up to fifteen miles away. This may sound strange, but the solution was to place landing lights all along the leading edge of the wings and turn the lights on. This would hide the airplane by matching the amount of light emissions from the airplane to the amount of light from the normal background brightness. Instead of having the submarine lookouts see a dark object on the horizon at fifteen miles, the approaching airplane would not be visible until it was three to five miles away. With this short range of detection, the submarine was not able to dive before the airplane was on top of the sub.
    Last edited by hk_mp5kpdw; 11-12-2002 at 03:05 PM.
    "Owners of dogs will have noticed that, if you provide them with food and water and shelter and affection, they will think you are god. Whereas owners of cats are compelled to realize that, if you provide them with food and water and shelter and affection, they draw the conclusion that they are gods."
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  11. #11
    A Banana Yoshi's Avatar
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    You'll need very good tech / electric bills to achieve invisibility.

    700 posts!! In 1 year that is
    Yoshi

  12. #12
    Much older and wiser Fountain's Avatar
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    Of course, how fantastic would it be to have the power to become invisible at will?

    Get working on it guys.
    Such is life.

  13. #13
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    My impression of the matter is that a covering that mimiced the coloration of the background would only work at a fixed angle of sight. for example...

    Code:
      (Blue stuff)              (White stuff)
                   \                   /
                     \              / 
                       \         /
                         \     /
                         Bob
                         /   \
                      /        \
                    /             \
                 /                   \
              /                         \
           Phil                       Steve
    Wiith Bob being invisible, the bottom of bob would have to be botth blue and white, or else either phil or steve would be able to see him.

    As for "light bending" you have other consequences. Something that is transparent to photons would not create disturbances in the electromagnetic spectrum, and therefore be invisible. This would be good.

    BUT

    Our eyes require that our retinas absorb photons. Without this we would not be able to see. This would be bad. Any other spectra of electromagnetic waves we were transparent to would cause problems as well, because we rely on many of them to operate.

    A more practical form of "invisibility" which does work is to simply absorb all photons that you are not backlit by. For example, wearing tan in the desert or wearing black at night.

  14. #14
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    im invisble! well pretty close
    Silent to All
    -Those who live by the sword get shot by those who don't.

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    It would get quite complicated, as you can see from my diagram. The other side of Bob's invisibility suit would have to produce rays going in the exact same direction, amplitude and frequency as every ray which struck the opposite side of him. (blue rays represent artificial rays) Mr Y would be in bob's shadow if the invisibility suit didn't work and mr x and mr z wouldnt be able to see him. Mr Z should be able to see mr X, etc.

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