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Duke University's underwater invisibility cloak stills troubled waters

Everyone's jumping on the invisibility cloaking bandwagon these days, but no one's quite managed to fully deliver on the promise. The same goes for two Duke University researchers who believe their mesh casing could grant the gift of concealment to underwater craft -- submarines, anyone? According to the proposed model, a specially designed shell punctuated by complex patterns of permeability and millimeter-sized pumps would eliminate the drag and turbulent wake caused by an object as it moves through the water. Utilizing the penetrable gaps in the case, water would at first accelerate, and then decelerate to its original speed before exiting -- rendering the fluid around the object virtually undisturbed. Now for the bad news: the design doesn't quite work for large-scale, real-world implementations -- hello again, submarines -- since the tech can only cloak small structures, like "a vehicle one centimetre across... [moving] at speeds of less than one centimetre per second." It's a massive bummer, we know, but we're getting there folks -- you just won't see it when it actually happens.