Filed under: Misc. GadgetsApparently not content with simply building an invisibility cloak, of sorts, those mad scientists at Duke University's Pratt School of Engineering now say that they've found that a three-dimensional "sound cloak" is also possible, in theory. According to Duke's Steven Cummer, the researchers have come up with a "recipe" for an acoustic material that would "essentially open up a hole in space and make something inside that hole disappear from sound waves." Needless to say, they haven't tested that possibility just yet, but they say it could one day be used to hide submari
