From the perspective of technical analysis, profit-taking near all-time highs and the need for a retest of lower support levels are normal processes for most cryptocurrencies. In fact, a quick glance over discussions by many analysts and traders on Twitter shows that most expected BTC to revisit lower support levels at $64,000 and below before recapturing bullish momentum and moving higher.
Blocks are linked together by cryptography – complex mathematics and computer science. Any attempt to alter data disrupts the cryptographic links between blocks, and can quickly be identified as fraudulent by computers in the network.

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Long term relationships also strengthen, to some extent, around areas indicated as bubbles. The previously observed long term relationship between Google Trends and Bitcoin price [8] can also be seen here, between late 2012 and 2014 (period band 64–256). With the benefit of extra data it can be observed that the relationship disappears around 2014 (for lower period bands) and 2015 (for higher period bands), before the relationships start occurring more consistently in 2016 and 2017 (a region with a number of bubbles identified). The previously observed relationship between Wikipedia views and Bitcoin observed in 2013 (64–128 band), disappears before again returning in mid-2016 and 2017.