Google has officially announced that it’s achieved quantum supremacy in a new article published in the scientific journal Nature. The announcement comes exactly one month after it initially leaked, when Google’s paper was accidentally published early. Now, however, it’s official, meaning the full details of the research are public, and the broader scientific community can fully scrutinize what Google says it’s achieved.

Google says that its 54-qubit Sycamore processor was able to perform a calculation in 200 seconds that would have taken the world’s most powerful supercomputer 10,000 years. That would mean the calculation, which involved generated random numbers, is essentially impossible on a traditional, non-quantum computer.

Unsurprisingly, IBM, the company that operates the supercomputer that Google claims to have beaten, and a key quantum computer competitor, is disputing Google’s claims. In a blog post published pre-emptively on Monday, the company said that the same task could be performed on a classical system in just 2.5 days, rather than the 10,000 years that Google is claiming. IBM says that Google “failed to fully account for plentiful disk storage” when estimating how long its traditional supercomputer would take to perform the calculation.

Despite IBM’s attempts to downplay Google’s achievement, many in the research community welcomed the news, with scientists quoted by The New York Times likening Google’s breakthrough to the Wright brothers’ first plane flight in 1903. We may still be years away from having quantum computers that are useful for practical tasks, but Google’s findings could finally have provided proof that such a future is possible in the first place.