Wi-Fi was born from a failed search for exploding black holes

The wireless signal in your home traces back to a cosmic hunt that came up empty. In the 1990s, radio astronomer John O’Sullivan and his team at Australia’s national science agency, the CSIRO, were trying to detect the faint radio flashes expected from tiny exploding black holes, hypothetical specks predicted to evaporate in a final burst.

The problem was that radio waves from deep space arrive smeared and tangled, blurred as they cross the cosmos. To clean them up, the team built signal-processing methods around mathematics called fast Fourier transforms, designed to pull a sharp signal out of a mess of noise.

They never bagged a black hole. But O’Sullivan’s group realized the same trick solved a stubborn earthly problem. Indoors, wireless signals bounce off walls and furniture, arriving as a jumble of echoes that scrambles data, exactly the kind of smearing they’d already learned to undo.

“Their solution came from John’s efforts to hear the faint radio whispers of exploding black holes.”

They took those Fourier techniques off the shelf and applied them to wireless networking, unsmearing the signal so data could travel fast and reliably through a cluttered room. In 1996 the US Patent and Trademark Office granted CSIRO a patent that became foundational to modern Wi-Fi. The technology now sits in well over 15 billion devices — phones, laptops, TVs, routers — all running on math meant to catch a dying star.