Can Quantum Computing Break Bitcoin?

One of the most groundbreaking innovations of Bitcoin is its security. But what if that security was compromised?

This morning over breakfast, my wife posed the question to me about the future of quantum computing, and what effect it would have on the world of blockchain. I began digging into the question to see what experts were saying.

The first alarmingheadline I found was this: "Is Bitcoin at Risk as Google and IBM Aim for 50-Qubit Quantum Computers?" However, the article itself was written to alleviate fears posed by this potential threat. It cited two reasons why we should not be worried. Firstly, Satoshi Nakamoto, the pseudonymous founder of Bitcoin, knew about the potentially drastic increases in computing power and compensated for this in his protocol. Secondly, the article claimed that governments and companies lack the incentive to hack Bitcoin. The argument basically states that, if a government could hack Bitcoin, why would they, revealing they had the capabilities and spurring their enemies to upgrade their cryptography?

The next article I read quoted the co-founder of a cybersecurity firm called Post Quantum, Andersen Cheng, as saying, "Bitcoin will expire the very day the first quantum computer appears." If I had a satoshi for every time somebody said Bitcoin was dead or dying...

This Forbes article alleviated any remaining fears I had. Both a quantum computer expert employed by Google, John Martinis, and two cryptographers in the cryptocurrency spaced seemed unphased. To quote one, "In the grand scheme of risks and threats, it will take 20 to 30 years to be a real threat and by that time, we will have better signature schemes."

This is definitely something to keep an eye on, but not something to worry about.