Researchers are saying new materials, which they call "metamaterials", can change the way light and other forms of radiation bend around an object and this may offer a method to make objects invisible.
Harry Potter's cloak or The Invisible Man of films and fiction might be a bit harder to emulate, however, because the materials must be used in a thick shell.
The concept begins with refraction - a quality of light in which the electromagnetic waves take the quickest, but not necessarily the shortest, route.
This accounts for the illusion that a pencil immersed in a glass of water appears broken, for instance.
"Imagine a situation where a medium guides light around a hole in it," physicist Ulf Leonhardt of Britain's University of St Andrews, wrote in one of the reports, published in Friday's issue of the journal Science.
The light rays end up behind the object as if they had travelled in a straight line.
"Any object placed in the hole would be hidden from sight. The medium would create the ultimate optical illusion: invisibility," Mr Leonhardt wrote.
"Such devices may be possible. The method developed here can be also applied to escape detection by other electromagnetic waves or sound."
The theory is different from that used on modern "stealth" bombers, for example, which bounce radar off their surfaces so they cannot be seen.
Instead, an object would be encased in a shell of metamaterials and they would create an illusion akin to a mirage, said David Schurig of Duke University in North Carolina, who worked on the second report.
Metamaterials are composite structures that deliberately resemble nothing found in nature. They are engineered to have unusual properties, such as the ability to bend light in unique ways.
Like all physics, the invisibility idea requires a little imagination.
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