Silence.

The most silent place on Earth at the moment seems to be a room in Minneapolis- an anechoic chamber at Orfield Labs. The anechoic chambers are rooms which are completely isolated from outside noise and are designed in a way that they absorb sound without reflecting any back into the room. There are many anechoic chambers in the world but what makes the one at Orfield Labs "the quietest" is the fact that the noise level measured in the anechoic chambers is usually around 10 dBA and in the one in Minneapolis is -9,4 dBA. The human ear detects sounds above 0 dBA.

© Orfield Labs

When one spends some time in this room, one would expect to experience the absolute silence. But although one experiences the total absence of sound outside the body, one becomes extremely aware of the sounds inside our bodies- the heart beat, the sound of lungs as you inflate and deflate, the pulse of blood through veins and arteries. These sounds become so disturbing that no person so far could stand to be in this room for more than 45 minutes. People usually experience disorientation and visual and auditory hallucinations.

It is exactly this experience - the visit to one of the anechoic chambers, that made John Cage write the famous piece 4'33". His search for "nothingness", for the absolute silence, for Zen in music, led him to the anechoic room where he was utterly surprised to hear sounds, realizing those were the sounds of his own body. This experience had such a profound effect on Cage, helping him understand that "there's no such thing as silence".

“There is no such thing as an empty space or an empty time. There is always something to see, something to hear. In fact, try as we may to make a silence, we cannot.”
~John Cage