The hiss of a radio between stations is more than just interference. A significant part of this noise is born from the quantum vacuum itself — the invisible fabric of the world, which is far from empty. This trembling arises whenever something changes: for example, an electric current in a wire disturbs the vacuum, and it responds with a vibration, like a taut string. Each change leaves its imprint, and these imprints accumulate into audible noise.

This mechanism also operates on cosmic scales. In its infancy, the Universe underwent a sudden inflation — and the vacuum noise froze into gravitational ripples, which we now detect as echoes of the Big Bang. Most surprisingly, part of the familiar radio hiss is a direct legacy of that era, stretched by expansion into radio waves.

Quantum fuzziness, where a particle can exist in multiple states at once, fades over time — this is called decoherence. The vacuum simply 'forgets' its previous forms, and the world settles into everyday stability. In this way, radio noise, the birth of galaxies, and even dark matter are linked. Alan Guth, Rainer Weiss, and Wojciech Zurek showed that wave function collapse during measurement, the expansion of the universe, and gravity are all parts of a single picture painted by an ever-trembling vacuum.