Purpose. We develop new quantitative methods to estimate the level of speculation and long-term sustainability of Bitcoin and Blockchain. Design/Methodology/Approach. We explore the practical application of speculative bubble models to cryptocurrencies. We then show how the approach can be extended to provide estimated brand values using data from Google Trends. Findings. We con�rm previous �ndings of speculative bubbles in cryptocurrency markets. Relatedly, Google searches for cryptocurrencies seem to be primarily driven by recent price rises. Overall results are su�cient to question the long-term sustainability of Bitcoin with the suggestion that Ethereum, Bitcoin Cash and Ripple may all enjoy technical advantages relative to Bitcoin. Our results also demonstrate that Blockchain has a distinct value and identity beyond cryptocurrencies { providing foundational support for the second generation of academic work on Blockchain. However, a relatively low estimated long-term growth rate suggests that the bene�ts of Blockchain may take a long time to be fully realised. Originality/value. We contribute to an emerging academic literature on Blockchain and to a more established literature exploring the use of Google data within business analytics. Our original contribution is to quantify the business value of Blockchain and related technologies using Google Trends.

中文翻译：

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量化比特币和区块链的可持续性

目的。我们开发了新的量化方法，以评估投机水平和比特币和区块链的长期可持续性。设计/方法论/方法。我们探索投机泡沫模型在加密货币上的实际应用。然后，我们展示如何使用Google趋势中的数据扩展该方法以提供估计的品牌价值。发现。我们确认了加密货币市场上投机泡沫的先前发现。相关地，谷歌搜索加密货币似乎主要是由于最近的价格上涨。总体结果足以质疑以太坊，比特币现金和瑞波币相对于比特币都具有技术优势的比特币的长期可持续性。我们的结果还表明，区块链具有超越加密货币的独特价值和身份{为第二代区块链学术工作提供基础支持。但是，相对较低的估计长期增长率表明，区块链的好处可能需要很长时间才能完全实现。创意/价值。我们为有关区块链的新兴学术文献做出贡献，并为探索在业务分析中使用Google数据的更成熟文献做出贡献。我们最初的贡献是使用Google趋势量化区块链和相关技术的商业价值。创意/价值。我们为有关区块链的新兴学术文献做出贡献，并为探索在业务分析中使用Google数据的更成熟文献做出贡献。我们最初的贡献是使用Google趋势量化区块链和相关技术的商业价值。创意/价值。我们为有关区块链的新兴学术文献做出贡献，并为探索在业务分析中使用Google数据的更成熟文献做出贡献。我们最初的贡献是使用Google趋势量化区块链和相关技术的商业价值。