Harry Potter's Magic Used by Scientists

The cloak of invisibility is not just for Harry Potter anymore. Physicists now have the mathematical equations to make objects invisible by bending light.

Engineers at Purdue University in Indiana have created a device using those calculations. Very soon, the device should be able to make objects large or small disappear. The theory of the design uses tiny metal needles that are fitted into a cone, which is somewhat round in shape like a hairbrush at specific angles that force light to go around the cloak, thus bending the light. Everything that is inside the cone will appear to have vanished since the light will not be reflecting off it.

Vladimir Shalaey, professor of electrical and computer engineering at Purdue says, "I realize it looks like fiction, however it does agree with the laws of physics." Shalaey continued to say, "Since there will hardly any metal in it the device will not be as heavy as Harry Potter's cloak."

The design although still in theory is to be published this month in Nature Photonics.

Shaleay will need two to three years to develop a working prototype and is currently working on securing funding for the project.

There is one major limitation with the design; it currently can only bend the light of a single color. It cannot bend light of the full visible spectrum at one time. To develop a device to work with all visible light colors is going to be a huge technical challenge. According to Shalaey, the device is still possible and the principle is doable.

Shaleay said that there are still useful applications for the device even when blocking a single frequency. The device could be used in the military to protect the soldiers from night vision goggles, which use a single frequency. The military could also use the device to hide objects from laser designators used to light up a target.

The design can cloak objects large or small in the light range visible to humans.

All materials have their own specific range of light refraction that is used to determine how light bends. A good example of light refraction is placing a stick or similar object into a glass of water and notice how the stick looks bent when looking through the outside of the glass.

The materials that are used to make the tiny needles are currently being used to make nanotech devices.

Sources:
http://news.yahoo.com/s/afp/20070406/sc_afp/ussciencephysicsinvisibility;_ylt=AqzJv7AbmCXR9NeichSy_KsPLBIF