I discuss private and central-bank-issued digital currencies, summarizing my prior research. I argue that prices of private digital currencies such as bitcoin follow random walks or, more generally, risk-adjusted martingales. For central bank digital currencies, I argue that they enhance the trilemma facing a central bank. Of the three objectives, price stability, efficiency, and monetary trust, the central bak can achieve at most two.

中文翻译：

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关于数字货币

我讨论了私人和央行发行的数字货币，总结了我之前的研究。我认为比特币等私人数字货币的价格遵循随机游走，或者更一般地说，遵循风险调整鞅。对于央行数字货币，我认为它们加剧了央行面临的三难困境。在价格稳定、效率和货币信任这三个目标中，中央银行最多可以实现两个目标。