'Electromagnetic Wormhole' Possible with Invisibility Technology

Oct 12, 2007
'Electromagnetic Wormhole' Possible with Invisibility Technology
One of the views through the "wormhole." Different lengths result in different bending of light. Credit: University of Rochester

The team of mathematicians that first created the mathematics behind the "invisibility cloak" announced by physicists last October has now shown that the same technology could be used to generate an "electromagnetic wormhole."

In the study, which is to appear in the Oct. 12 issue of Physical Review Letters, Allan Greenleaf, professor of mathematics at the University of Rochester, and his coauthors lay out a variation on the theme of cloaking. Their results open the possibility of building a sort of invisible tunnel between two points in space.

"Imagine wrapping Harry Potter's invisibility cloak around a tube," says Greenleaf. "If the material is designed according to our specifications, you could pass an object into one end, watch it disappear as it traveled the length of the tunnel, and then see it reappear out the other end."

Current technology can create objects invisible only to microwave radiation, but the mathematical theory allows for the wormhole effect for electromagnetic waves of all frequencies. With this in mind, Greenleaf and his coauthors propose several possible applications. Endoscopic surgeries where the surgeon is guided by MRI imaging are problematical because the intense magnetic fields generated by the MRI scanner affect the surgeon's tools, and the tools can distort the MRI images. Greenleaf says, however, that passing the tools through an EM wormhole could effectively hide them from the fields, allowing only their tips to be "visible" at work.

To create cloaking technology, Greenleaf and his collaborators use theoretical mathematics to design a device to guide the electromagnetic waves in a useful way. Researchers could then use these blueprints to create layers of specially engineered, light-bending, composite materials called metamaterials.

Last year, David R. Smith, professor of electrical and computer engineering at Duke's Pratt School, and his coauthors engineered an invisibility device as a disk, which allowed microwaves to pass around it. Greenleaf and his coauthors have now employed more elaborate geometry to specify exactly what properties are demanded of a wormhole's metamaterial in order to create the "invisible tunnel" effect. They also calculated what additional optical effects would occur if the inside of the wormhole was coated with a variety of hypothetical metamaterials.

Assuming that your vision was limited to the few frequencies at which the wormhole operates, looking in one end, you'd see a distorted view out the other end, according the simulations by Greenleaf and his coauthors. Depending on the length of the tube and how often the light bounced around inside, you might see just a fisheye view out the other end, or you might see an Escher-like jumble.

Greenleaf and his coauthors speculated on one use of the electromagnetic wormhole that sounds like something out of science fiction. If the metamaterials making up the tube were able to bend all wavelengths of visible light, they could be used to make a 3D television display. Imagine thousands of thin wormholes sticking up out of a box like a tuft of long grass in a vase. The wormholes themselves would be invisible, but their ends could transmit light carried up from below. It would be as if thousands of pixels were simply floating in the air.

But that idea, Greenleaf concedes, is a very long way off. Even though the mathematics now says that it's possible, it's up to engineers to apply these results to create a working prototype.

Greenleaf's coauthors are Matti Lassas, professor of mathematics at the Helsinki University of Technology; Yaroslav Kurylev, professor of mathematics at the University College, London; and Gunther Uhlmann, Walker Family Endowed Professor of Mathematics at the University of Washington.

Source: University of Rochester

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not rated yet Feb 14, 2009
My name is Michael a 41year old male residing in NZ. Please don't treat this as a hoax as I don't talk of my experience to anybody. Approximately 33years ago on my way to school I had a very vivid experience of what I would call a wormhole. I remember the whole experience very clearly and I recall almost precisely what I was doing to create this experience and believe it can be recreated. At the time I don't think there was a publicised theory of wormholes but I remember it as being a bright white tunnel with segments, prior to entering the tunnel there was a purple green film such as a petrol or oil spill in water. When I returned from this wormhole I had walked 20meters unaware I was still walking which suggests time as we know it continues while in a wormhole, but whether or not it is at the same rate I am not sure. The ironic thing is when I became aware that I had just been somewhere I looked down and picked up a worm that was drying out in the sun, I wet it and threw it to the grass. I was very inquisitive and had deep thought as a child, at the time I was trying very hard to figure out what created the beginning of the universe, what created the "Big Bang". So effectively, as this is a genuine experience these factors would have to suggest I was in fact travelling in a wormhole and the existence of such is directly related to the conceptual "universal creation". I am most interested to find out when the name "wormhole" was given and who named it? I have in the last 7years or so had strange types of phenomena occur around me possibly in the form of electromagnetic disturbance and believe with the correct equipment and personnel it will be very easy to observe and will aid in the research of the elusive wormhole.

New Zealand.

May 11, 2009
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