'Q-Day Bounty' controversy spreads... Google researcher criticizes "Quantum attacks are meaningless"

Based on elliptic curve cryptography(ECC) such as Bitcoin(BTC) assets face the “quantum computing threat,” but the “1 BTC Q-Day Prize” competition initiated by Project Eleven has evolved into a debate about the legitimacy of the contest.

Google(Google) quantum computing team researcher Craig Gidney(Craig Gidney) criticized in his blog post “QDay Prize’s Predictability Failure” on April 25( local time) that the winning results did not demonstrate progress toward “cryptographically meaningful quantum attacks,” and pointed out that the premise of the competition used benchmarks unsuitable for current quantum computers.

While the “cracking” of 15 ECC keys by the results expanded market information,

Project Eleven previously announced on April 24 that Giancarlo Lelli(Giancarlo Lelli) successfully cracked 15-bit elliptic curve keys using publicly accessible quantum hardware and awarded him the Q-Day Prize. The project defined this as “the largest-scale ECC quantum attack in history,” emphasizing that compared to previous demonstrations of 6 bits, this represents a 512-fold leap.

The issue is that the publicity of this achievement is linked to the long-term security assumptions of digital assets worth approximately $2.5 trillion(about 3.675 quadrillion Korean won, with an exchange rate of 1 USD = 1470.20 KRW), protected by ECC, including Bitcoin(BTC) and Ethereum(ETH). Depending on how seriously the quantum threat level is regarded as “real,” market anxiety and response speed may also change, making the way it is expressed a sensitive issue.

“Without error correction, it’s meaningless”… Claiming that “luck” created the results

Gidney’s core controversy is that, for Shor’s algorithm(Shor’s algorithm) to reach a “cryptographically meaningful” scale, quantum error correction(quantum error correction) is necessary. He emphasizes: “Currently, quantum computers experience about one error per 1,000 gates, but cryptographically meaningful Shor’s algorithm requires billions of gates,” and the only known way to bridge this gap is through error correction, which is still ongoing.

He also pointed out that small-scale Shor-type problems may “appear successful” even if quantum hardware makes no substantial contribution. He relates this to a satirical paper he published in SIGBOVIK 2025(on the possibility of reproducing the same results through randomness), explaining it as a “Falling With Style” problem, and cites GitHub user Yuval Adam(Yuval Adam) who noted that even if the quantum calls in the winning submission are replaced with random calls, the results are “indistinguishable.”

Project Eleven “Benchmarks are imperfect, but guiding open experiments remains necessary”

Project Eleven interprets this result as a “practical demonstration” of a threat type that could attack Bitcoin(BTC) and Ethereum(ETH). CEO Alex Pruden(Alex Pruden) argues that, because the experiment used publicly accessible cloud hardware, the barrier to entry is lowering, which signals that the resource requirements for such attacks are decreasing.

However, Pruden also partially accepted Gidney’s point on “small factorization problems being an extremely imperfect measure of Q-Day,” and expressed the need for a mechanism to bridge the gap between the accelerated awareness in quantum research circles and the “strong evidence” demanded by cryptography and Bitcoin developers. Gidney did not deny the quantum risks faced by cryptographic assets, but he pointed out that if results that can be randomly reproduced spread widely, it might not be a warning but rather “ammunition” for skeptics. Therefore, benchmark design becomes a variable in assessing the credibility of quantum threat information. As of press time, Bitcoin(BTC) trading price is $77,750.