The mathematics behind nearly every Wi-Fi signal in the world was originally developed to detect exploding black holes. CSIRO, the Australian government's national science agency, developed the algorithm in the early 1990s for use in radio astronomy. By the end of the decade, that same algorithm had also solved the biggest problem in indoor wireless networking. The associated patents brought CSIRO over a billion Australian dollars.

In the early 1990s, John O'Sullivan and a small team at CSIRO were working on a problem in radio astronomy. They wanted to detect very faint radio bursts from primordial black holes — tiny black holes left over from the early universe that, according to a prediction by Stephen Hawking, should evaporate explosively in detectable signals.

The challenge was that radio signals from space arrive at Earth through a noisy atmosphere, scattered and distorted by reflections and interference. To pull a clean signal out, the team developed a combination of a fast Fourier transform with sophisticated correction for multipath interference.

Around the same time, the emerging IEEE 802.11 wireless networking standard was failing badly inside buildings. Wi-Fi signals bounced off walls, furniture, and people, arriving at receivers as overlapping echoes. The multipath problem was the central technical obstacle to indoor Wi-Fi, and no one had a fast or cheap solution.

Australian engineers realized that the same mathematics that cleaned up cosmic radio bursts could clean up bouncing Wi-Fi signals.

CSIRO patented the technique in 1996. Over the next two decades, the agency sued or licensed nearly every major manufacturer of Wi-Fi-enabled devices — Apple, Microsoft, Intel, Hewlett-Packard, Cisco, and many others. The royalties exceeded one billion Australian dollars by the time the core patents expired.

The exploding black holes Hawking predicted were never observed. The Wi-Fi worked.