WASHINGTON - The creation of an invisibility cloak like the one used by Harry Potter in J.K. Rowling's books is theoretically possible, scientists said in two studies published this week by the online Science Express journal.
The key to making an object invisible is to surround it with a cloak made of "metamaterials" that are engineered to bend light around an object, continuing on the other side in the same direction as before, according to Ulf Leonhardt, author of one of the studies.
Sound waves, which have a longer wavelength than light, can be distorted in such a way, and light bends naturally.
"All one has to do is enhance this bending effect and control it better," said Leonhardt, professor of theoretical physics at the University of St. Andrews in Scotland. "We've given recipes of how to do this. You have to control structures that are smaller than the wavelength of light - less than half a micrometer," he said. A micrometer is a millionth of a meter.
The authors of the papers set out mathematical requirements for a theoretical metamaterial, that could achieve invisibility.
The applications for such a device include protecting structures from vibrations, improving wireless communications, seeing through obstructions, and hiding objects, David Schurig, a scientist at Duke University, and co-author of the second paper, said.
Two Duke scientists are now working on building the proposed "metamaterial," and the first device would be a few millimeters across, according to Imperial College in London.
When built, a final theoretical device would have the same effects as the magical cloak in Rowling's magical books, the British school said.
"Just as in the Harry Potter film, nobody would be able to see an object if it was cloaked, as it's in a spacewarp, and that's exactly what our stuff would do," said John Pendry, a professor at Imperial College and co-author of one of the papers.
Such a cloak does not yet exist, but early versions that could mask microwaves and other forms of electromagnetic radiation could be as close as 18 months away, Pendry said. He said the studies were "an invitation to come and play with these new ideas."
"We will have a cloak after not too long," he said.
The Pentagon's Defense Advanced Research Projects Agency supported the research, given the obvious military applications of such stealthy technology.
While Harry Potter could wear his cloak to skulk around Hogwarts, a real-world version probably would not be something just to be thrown on, Pendry said.
"To be realistic, it's going to be fairly thick. Cloak is a misnomer. "Shield' might be more appropriate," he said.
The Science Express is the online advance publication of the journal Science.
ado patta neda...
The key to making an object invisible is to surround it with a cloak made of "metamaterials" that are engineered to bend light around an object, continuing on the other side in the same direction as before, according to Ulf Leonhardt, author of one of the studies.
Sound waves, which have a longer wavelength than light, can be distorted in such a way, and light bends naturally.
"All one has to do is enhance this bending effect and control it better," said Leonhardt, professor of theoretical physics at the University of St. Andrews in Scotland. "We've given recipes of how to do this. You have to control structures that are smaller than the wavelength of light - less than half a micrometer," he said. A micrometer is a millionth of a meter.
The authors of the papers set out mathematical requirements for a theoretical metamaterial, that could achieve invisibility.
The applications for such a device include protecting structures from vibrations, improving wireless communications, seeing through obstructions, and hiding objects, David Schurig, a scientist at Duke University, and co-author of the second paper, said.
Two Duke scientists are now working on building the proposed "metamaterial," and the first device would be a few millimeters across, according to Imperial College in London.
When built, a final theoretical device would have the same effects as the magical cloak in Rowling's magical books, the British school said.
"Just as in the Harry Potter film, nobody would be able to see an object if it was cloaked, as it's in a spacewarp, and that's exactly what our stuff would do," said John Pendry, a professor at Imperial College and co-author of one of the papers.
Such a cloak does not yet exist, but early versions that could mask microwaves and other forms of electromagnetic radiation could be as close as 18 months away, Pendry said. He said the studies were "an invitation to come and play with these new ideas."
"We will have a cloak after not too long," he said.
The Pentagon's Defense Advanced Research Projects Agency supported the research, given the obvious military applications of such stealthy technology.
While Harry Potter could wear his cloak to skulk around Hogwarts, a real-world version probably would not be something just to be thrown on, Pendry said.
"To be realistic, it's going to be fairly thick. Cloak is a misnomer. "Shield' might be more appropriate," he said.
The Science Express is the online advance publication of the journal Science.
ado patta neda...
