- For fans of the fictional Harry Potter, US and British scientists have demonstrated a working "invisibility cloak" that could, in time, make wearers disappear.
Initial tests focused on making objects invisible to microwaves, but the scientists said the same principles could theoretically apply to visible frequencies, making a true invisibility cloak like storybook hero Potter's possible. ...
... The material is designed to distort space so that microwaves are not reflected back, but are instead bent around the cloaked object, whatever its shape, and allowed to flow on as if it didn't exist.
The result is that the beams are deflected like water flowing around a rock in a river, without noticeably interrupting the main current.
"By incorporating complex material properties, our cloak allows a concealed volume, plus the cloak, to appear to have properties similar to free space when viewed externally," said Duke scientist David Smith.
"The cloak reduces both an object's reflection and its shadow, either of which would enable its detection." (full story)
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