While heavy metal acts and dubstep upstarts battle over who can make the loudest racket, scientists may have discovered the ‘quietest sound in the universe’. No… it’s not the sound of Madonna lip-synching, but instead something called the quantum phonon.

According to Discover Magazinephysicists have discovered the softest possible sound in the world, a subatomic acoustical wave which can only detected by fine scientific instruments that can detect the smallest difference between silence and audible effects.

A team at Sweden’s Chalmers University of Technology, led by physicist Per Delsing, created such an instrument – a kind of bionic era – to tune into the micro frequencies of the quantum phonon. Delsing’s quantum microphone is built onto of a semiconductor microchip a mere two-tenths of an inch long.

Not only is it tiny, but its freezing, with the minuscule microphone frozen atop the microchip an temperatures of -273 degrees celsius. The freezing is to offset any vibrations which would be detected as noise by the quantum microphone. The barely inaudible quantum phonon sound is then produced by two microscopic aluminium cones that connect via an electrical field that generates extremely faint sound waves that bounce back and forth.

The full description is pretty technical, but essentially Delsing’s microphone is picking up the smallest of wave signals, of “a few quintillionths of a meter high”, with Delsing adding, “that’s much less than the size of a proton!”

Its the first time that phonons have ever been studied in action, but Delsing and his team are hoping to use their research to contribute to future development of computers. Essentially looking at replacing the standard forms of transforming information with the same microscopic sound waves. However, at this stage the Swedish scientific team are unsure what the effect of the barely audible sounds is when it passes through materials.

Of the discovery of the world’s quietest sound, Delsing says enthusiastically, ‘we can detect things that have not been possible to detect before;” adding that the potential for further discovery is possible, “we’ll have to see where that takes us.”

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