Quantum Physics Offers New Way to Generate Random Numbers

Encryption systems rely heavily on random numbers, which are vital for securing digital information. However, conventional computers struggle to generate truly random numbers. New research suggests that quantum physics might provide a solution.

The project conducted at ETH Zurich involved the use of two connected cryostats to cool superconducting units known as qubits. These qubits function based on the principles of quantum mechanics. The researchers in Switzerland spent a decade working on this project, with a budget of $12 million. Their findings were published in Nature last month, highlighting the generation of genuinely random numbers.

Random numbers are crucial for digital information security. Data traversing the internet relies on public and private keys. Private keys consist of hundreds of bits—zeros or ones—that encode extremely large numbers. While computers can approximate true randomness, they inherently follow specific processes, making true unpredictability elusive.

“If you knew what the computer was calculating, you would be able to predict it exactly,” explained Morgan W. Mitchell, a quantum physicist at the Institute of Photonic Sciences in Barcelona. Such predictability poses a risk; hackers often exploit mathematical weaknesses in encrypted systems to uncover random vulnerabilities and gain access to private keys.

The Swiss research team addressed this challenge through randomness amplification. This method enhances lower-grade random numbers using quantum physics, resulting in numbers that Dr. Mitchell described as “effectively perfect.” Although Dr. Mitchell was not part of the Swiss team, he praised their achievement.

While other researchers have recently achieved considerable advancements in random number generation, they have predominantly relied on computational methods. The Swiss experiment distinguishes itself by providing validation independent of processing power, showcasing a fundamental trust in physics.

According to Roger Colbeck, a professor of quantum information theory at King’s College London and an expert in quantum randomness, the paper from ETH Zurich presents the most compelling evidence that high-quality randomness can be derived from quantum processes. This research represents a significant milestone in the quest for secure encryption systems.