Physicists at the Nanyang Technological University in Singapore have published a new paper which lays the theoretical foundation for how submarines, with a special coating, could deflect sound.
This means submarines would be completely undetectable by sonar.
Authored by physicist Baile Zhang and his colleagues, the paper, published in Physical Review Letters, proposes that the same technique could apply to any 3D object. Normally, sonar waves hit the hull of a submarine and the sound scatters, which creates an echo, revealing the location of the sub.
Under Zhang’s system, sound waves sent out by sonar would hit a special material called a phononic crystal. This material is acoustically tuned and would manipulate the sound waves, such that they would bounce off and on the submarine in a loop, until finally the submarines passes through undetected.
For now, the coating is just a theory. But unlike other more fantastical proposals, Zhang says he and his team will get right to designing the coating in just a few months, as the project is very feasible.