Saturday, March 7, 2009

Scientists closer to making invisibility cloak a reality

http://seshdotcom.files.wordpress.com/2008/10/invisible-cloak.jpgJ.K. Rowling may not have realized just how close Harry Potter s invisibility cloak was to becoming a reality when she introduced it in the first book of her best-selling fictional series in 1998. Scientists however have made huge strides in the past few years in the rapidly developing field of cloaking. Ranked the number five breakthrough of the year by Science magazine in 2006 cloaking involves making an object invisible or undetectable to electromagnetic waves. A paper published in the March 2009 issue of SIAM Review "Cloaking Devices Electromagnetic Wormholes and Transformation Optics " presents an overview of the theoretical developments in cloaking from a mathematical perspective. One method involves light waves bending around a region or object and emerging on the other side as if the waves had passed through empty space creating an "invisible" region which is cloaked. For this to happen however the object or region has to be concealed using a cloaking device which must be undetectable to electromagnetic waves. Manmade devices called metamaterials use structures having cellular architectures designed to create combinations of material parameters not available in nature.  ... The cloaking version of a wormhole allows for an invisible tunnel between two points in space through which electromagnetic waves can be transmitted. Some possible applications for cloaking via electromagnetic wormholes include the creation of invisible fiber optic cables for example for security devices and scopes for MRI-assisted medical procedures for which metal tools would otherwise interfere with the magnetic resonance images. The invisible optical fibers could even make three-dimensional television screens possible in the distant future. The effectiveness and implementation of cloaking devices in practice however are dependent on future developments in the design investigation and production of metamaterials. The "muggle" world will have to wait on further scientific research before Harry Potter s invisibility cloak can become a reality.

via Scientists closer to making invisibility cloak a reality.

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