Quantum computers outperform classical ones, with results you can trust

AI 中文解读

IBM在量子计算领域取得突破，宣布成功演示了三种「量子优势」——这意味着量子计算机在特定任务上干得比传统计算机更好，而且结果还经得起验证。这对一直困扰学界的问题给出了令人信服的答案：现阶段的量子计算机虽然硬件不完美、容易出错，但终于能跑出传统电脑无法复现的正确结果了。所谓量子优势，过去只在理论算法中存在：量子计算机理论上能算得快得离谱，但实际机器要么根本跑不了这些算法，要么只能跑简化版，以至于传统电脑也能轻松搞定。更头疼的是，如果你真算出一个传统电脑无法验证的结果，连科学家都很难确认你算对了没有。IBM这次用三种不同的纠错和验证方法，让量子计算机的运算结果变得「可信」。首席科学家说得很直白：当你能用传统模拟来验证时，可信不重要；当传统模拟已经无能为力了，可信就至关重要。对普通人来说，这次进步短期内不会让你马上用上量子手机，但它意味着量子计算正在从理论走向实用。未来药物研发、新材料设计、金融风险模拟这些需要海量计算的领域，可能会因此加速。就像当年第一台电子计算机诞生一样，虽然普通人无法直接使用，但时代的车轮已经开始转动。

There are many algorithms for which it has been mathematically proven that a quantum computer can generate results that would take a classical computer an unreasonable amount of time to generate. Unfortunately, today's quantum computers either can't run those algorithms or can only run simplified versions that classical computers can also handle. This has left the field facing a challenging question: Can we demonstrate the promise of quantum computers on today's noisy, limited hardware? That's a more difficult question than it may first appear. If you generate a result that's out of reach of today's regular computers, it may not be possible to verify that you got the right result. And given that today's quantum computers are somewhat error-prone, getting the wrong result is a distinct possibility. Further, in the absence of a mathematical proof of the capabilities of quantum hardware, it's possible that a better classical algorithm could outperform the quantum hardware. These issues inspired IBM to launch a quantum advantage tracker. On Thursday, the company announced three new entries that it says clearly show a quantum advantage, each using a different approach to overcoming errors and validating quantum results. "Trusted computing when you can do classical simulations is irrelevant," IBM's Jay Gambetta told Ars. "Trusted computing when you can't do classical simulations is a big deal."Read full article Comments