By Devin Powell
A new cloak that hides objects from sound could really confuse a bat trying to echolocate in a cave. Sound waves striking a bump covered by the cloak bounce back as if they hit a flat wall instead.
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This sound-bending trick could smooth out the acoustics of concert hall walls. If adapted for water, it might also be useful for hiding submarines from sonar.
“The successful demonstration of a cloak that works for sound waves in air is a triumph,” says Che Ting Chan, a physicist at the Hong Kong University of Science and Technology, who was not involved in the research.