{"rewrite":{"id":"r_1e2f2c0c224632a386cdf009","clusterId":"c_31a0af2408d307c3657d331e","slug":"google-demonstrates-magic-state-cultivation-on-willow-quantum-processor","model":"deepseek-v4-1-flash","headline":"Google Demonstrates Magic State Cultivation On Willow Quantum Processor","summary":"Google Quantum AI reported that it carried out magic state cultivation on the Willow quantum processor and reduced the probability of error to about 1/40 of the uncultivated case. Fidelity, the measure of how close the produced state is to the ideal target, reached about 99.99%. The method prepares an imperfect magic state and discards trials where measurement detects a problem.","whyItMatters":"Magic states are the resource that lets a corrected quantum computer run operations beyond error correction alone, and a method that cuts their error rate by roughly 40 times with 99.99% fidelity on existing hardware attacks the step that has been consuming the largest share of processing capacity.","webCardHtml":"\u003cp\u003eThe method comes from a 2024 proposal by Craig Gidney and colleagues at Google Quantum AI. Instead of trying to build a perfect magic state from the start, it prepares a magic state containing errors in a small region of the processor, then examines it through measurements on multiple qubits. Trials where an error is detected are discarded, and only clean results are kept.\u003c/p\u003e\u003cp\u003eGenerating high-quality magic states is expensive: as much as 95% of a quantum computer\u0026#39;s processing capacity may go to producing them, and because they are consumed during use, they have to be regenerated as calculations proceed.\u003c/p\u003e","blueskyPost":"Google Quantum AI ran magic state cultivation on the Willow processor and cut error probability to about 1/40 of the uncultivated case, with fidelity of about 99.99%. The method discards trials where measurement finds a fault and keeps the clean ones.","twitterPost":"Google Quantum AI demonstrated magic state cultivation on Willow: error probability about 1/40 of the uncultivated case, fidelity about 99.99%. The method prepares an imperfect magic state, measures it, and discards bad trials.","threadsPost":null,"newsletterBlurb":"Google Quantum AI has demonstrated magic state cultivation on its Willow processor, reporting error probability about 1/40 of the uncultivated case and fidelity around 99.99%. The technique was proposed by Craig Gidney and colleagues in 2024 and works by preparing an imperfect magic state and discarding trials where measurement finds a fault. Magic states are consumed as computations run, so they must be generated again as needed.","attributionJson":"[{\"source\":\"GIGAZINE\",\"url\":\"https://gigazine.net/news/20261016-google-quantum-ai-magic-state-cultivation/\",\"title\":\"Google Demonstrates \\\"Magic State Cultivation\\\" on Quantum Processor \\\"Willow,\\\" Succeeds in Reducing Qubit Errors to About 1/40\"}]","lintFlagsJson":null,"lintHits":0,"costUsd":0,"inputTokens":4586,"outputTokens":609,"status":"published","repairAttempts":0,"nextRepairAt":null,"factsAttemptedAt":1792155140,"createdAt":"2026-10-16T12:48:33.000Z","publishedAt":"2026-10-16T12:51:10.000Z","updatedAt":"2026-10-16T12:51:10.000Z"},"cluster":{"id":"c_31a0af2408d307c3657d331e","canonicalTitle":"Googleが「魔法状態の培養」を量子プロセッサ「Willow」で実証、量子ビットのエラーを約40分の1に減らすことに成功","representativeArticleId":"a_f894169c7b827b5bb2424974","sourceCount":1,"writtenSourceCount":1,"writeAttempts":0,"isSolo":true,"entitiesJson":"{\"anime_titles\":[],\"manga_titles\":[],\"work_titles\":[],\"studios\":[],\"people\":[],\"type\":\"news\",\"domain\":\"other\",\"is_roundup\":false}","contentType":"news","status":"published","firstSeenAt":"2026-10-16T11:50:00.000Z","lastSeenAt":"2026-10-16T11:50:00.000Z","updatedAt":"2026-10-16T12:51:06.000Z"},"attribution":[{"source":"GIGAZINE","url":"https://gigazine.net/news/20261016-google-quantum-ai-magic-state-cultivation/","title":"Googleが「魔法状態の培養」を量子プロセッサ「Willow」で実証、量子ビットのエラーを約40分の1に減らすことに成功"}],"entities":{"anime_titles":[],"manga_titles":[],"work_titles":[],"studios":[],"people":[],"type":"news","domain":"other","is_roundup":false},"keyFacts":null}