Researchers at ETH Zurich report that they have created certified “perfect randomness” for the first time using a quantum Bell-test setup with two entangled superconducting chips connected by a 30-meter cooled link. “In the long term, this work could play a similar role in digital security to atomic clocks for timekeeping: a physically certified source of randomness that other systems can rely on,” Phys.org reports.
“Potential applications range from encryption of sensitive communications and digital identities to public randomness services for lottery applications and blockchain.”
From the post:
They call their method randomness enhancement. “This was made possible by an improved, so-called Bell-Test with simultaneously high quality and high data rate,” report Renato Renner and Andreas Wallraff. They and their colleagues use a complex setup consisting of two superconducting chips, which are cooled to very low temperatures close to absolute zero. Each chip represents a quantum bit, or qubit, which can assume the states “0” or “1” or any arbitrary superposition of these states. A 30-meter-long tube, which is also cooled, connects the two chips.
Microwave photons can bounce back and forth between themselves, creating quantum mechanical entanglement. This means that a quantum measurement on one qubit, which randomly yields the values “0” or “1”, automatically and remotely affects whether a “0” or “1” is measured on the second qubit. The 30-meter distance ensures that, during the measurement, even at the speed of light, no information can be exchanged between the qubits, as this would disrupt perfect randomness.
Wallraff and his team chose the exact type of measurement (or “base measurement” in technical terms) on the two qubits based on a random number generator. Renner’s colleagues were then able to further enhance the randomness of the measurement results using a special algorithm.
“The resulting sequence of zeros and ones is now truly perfectly random, and we can even verify that,” Renner says. He likens this result to this: “Technical improvements have allowed us, for the first time, to generate random numbers that will remain perfectly random for all eternity – regardless of the analytical methods used to assess their randomness.”
The findings have been published in the journal Nature.
https://doi.org/10.3929/ethz-c-000797430
Although the press releases will range from very select to rare, I said I'd pass...because sometimes the editors hide.
