Proof-of-Work (PoW) is a fundamental underlying technology behind most major blockchain cryptocurrencies. It has been previously pointed out that quantum devices provide a computational advantage in performing PoW in the context of Bitcoin. Here we make the case that this quantum advantage extends not only to all existing PoW mechanisms, but to any possible PoW as well. This has strong consequences regarding both quantum-based attacks on the integrity of the entirety of the blockchain, as well as more legitimate uses of quantum computation for the purpose of mining Bitcoin and other cryptocurrencies. For the first case, we estimate when these quantum attacks will become feasible, for various cryptocurrencies, and discuss the impact of such attacks. For the latter, we derive a precise formula to calculate the economic incentive for switching to quantum-based cryptocurrency miners. Using this formula, we analyze several test scenarios, and conclude that investing in quantum hardware for cryptocurrency mining has the potential to pay off immensely.
翻译:工作验证(PoW)是大多数主要链链加密背后的一个基本基础技术。 此前曾指出量子装置为Bitcoin在Bitcoin背景下执行PoW提供了计算优势。 在这里,我们证明这个量子优势不仅扩展到所有现有的PoW机制,而且扩大到任何可能的PoW。 这对基于量的对整个链的完整性的攻击,以及对为开采Bitcoin和其他加密目的更合理地使用量子计算进行量子计算,都具有强烈的后果。 首先,我们估计这些量子攻击何时将变得可行,对于各种加密来说,并讨论这种攻击的影响。 对于后者,我们想出一个精确的公式来计算向量子加密货币采矿者转变的经济激励。我们用这个公式分析了若干试验情景,并得出结论,对加密货币采矿的量子硬件投资有可能获得巨大回报。