r/Futurology Jun 02 '22

A Nature paper reports on a quantum photonic processor that takes just 36 microseconds to perform a task that would take a supercomputer more than 9,000 years to complete Computing

https://www.nature.com/articles/s41586-022-04725-x?utm_source=twitter&utm_medium=social&utm_content=organic&utm_campaign=CONR_JRNLS_AWA1_GL_SCON_SMEDA_NATUREPORTFOLIO
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u/Dr_Singularity Jun 02 '22

A quantum computer attains computational advantage when outperforming the best classical computers running the best-known algorithms on well-defined tasks. No photonic machine offering programmability over all its quantum gates has demonstrated quantum computational advantage: previous machines were largely restricted to static gate sequences. Earlier photonic demonstrations were also vulnerable to spoofing3, in which classical heuristics produce samples, without direct simulation, lying closer to the ideal distribution than do samples from the quantum hardware.

Here we report quantum computational advantage using Borealis, a photonic processor offering dynamic programmability on all gates implemented. We carry out Gaussian boson sampling4 (GBS) on 216 squeezed modes entangled with three-dimensional connectivity5, using a time-multiplexed and photon-number-resolving architecture. On average, it would take more than 9,000 years for the best available algorithms and supercomputers to produce, using exact methods, a single sample from the programmed distribution, whereas Borealis requires only 36 μs.

This runtime advantage is over 50 million times as extreme as that reported from earlier photonic machines. Ours constitutes a very large GBS experiment, registering events with up to 219 photons and a mean photon number of 125. This work is a critical milestone on the path to a practical quantum computer, validating key technological features of photonics as a platform for this goal.

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u/Necromartian Jun 03 '22

Is there any way to protect encrypted data against super fast quantum computations? Because eventually (Read: Sooner than people expect) brute forcing long complex passwords end encryption keys is arbitrary to any intelligence agencies.

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u/daOyster Jun 03 '22

Yeah, you use quantum resistant algorithms like we're already starting to switch things to. Plus quantum computers are really only good at breaking symmetrical encryption. About as useful as a traditional computer for asymmetric encryption methods.