Announcing our $6M seed round to build a quantum-ready future - read more here.
Quantum x Blockchain 101
You may have heard both of these statements, but which one is closer to the truth? And should you even care about this issue? Here are the facts:
Blockchain Security = "This math is too hard… for now"
What secures every Bitcoin and cryptocurrency asset is just math that assumes factoring big integers, solving discrete-log problems, or searching massive lists is impossible in any sort of reasonable time. Today, it's trivial to turn a private key into a public key, but completely infeasible to go from a public key back to its private key. Forward is easy; backward is assumed to be impossible. These hardness assumptions are the only wall between a thief and your coins.
Quantum turns a one-way function into a two-way function
Shor's algorithm would enable a large, fault-tolerant quantum computer to derive a private key from its public key. Grover's algorithm halves the complexity for brute forcing large search spaces like passwords. The one-way mirror that secures your private key becomes clear glass once a powerful enough quantum computer exists.
Blockchains share this single point of failure
Bitcoin, Ethereum, Solana, etc. rely on these assumptions, namely via their reliance on elliptic curve cryptography (ECC). Break these algorithms once and any wallet can be drained or spent. No 51% attack needed.
Regulators have scheduled the sunset
The United States National Institute of Standards and Technology (NIST) has set deadlines to deprecate these public key cryptosystems by 2030 and disallow them by 2035. Custodians, exchanges, and critical infrastructure will need to upgrade to post-quantum schemes before then to stay compliant and insurable.
Quantum hardware is being funded aggressively
After Q-Day, the day a powerful enough quantum computer exists, we cannot trust the signatures used to spend cryptocurrency, and trillions of dollars in value could be wiped out. It is estimated that over $50 billion has been spent to research and build quantum computers*, and the simplest method to recoup a quantum computer investment is by using it to retrieve "lost" cryptocurrency, or conduct a "non-attributional attack" on large, vulnerable holders.
Creating one of these machines has changed from being a science problem to an engineering problem - Don't believe us? Read these.
*It's important to note that much of the progress on quantum computing is non-public. Therefore, we cannot perfectly pinpoint where we are in relation to Q-Day.
Blockchains move really, really slowly
Many blockchain communities move notoriously slowly around contentious upgrades, and rightly so, as upgrades to the core protocol can risk introducing critical bugs and security vulnerabilities. Wallets must upgrade to support post-quantum cryptography, protocols must fork, hardware-wallets need new firmware, and most importantly every single holder must upgrade their keys to suitable post-quantum equivalents. This will not happen overnight.
To answer the original question… Should you care?
Quantum is a well-defined engineering threat on a 3-10 year time horizon. We must act now to propose upgrades, test assumptions, rotate keys, create post-quantum roadmaps, and ensure our security assumptions hold as these machines come online.
If this has piqued your interest and you want to learn more, consider the below resources your perfect beginner's guide to understand:
What is quantum computing?
How does it intersect with blockchains?
What are the leading strategies to secure blockchains in a post-quantum world?
Here are your first resources to get started:
Quantum Computers Explained:
Post-Quantum Blockchains:
Quantum Computers and the Bitcoin Blockchain:
https://www.deloitte.com/nl/en/services/risk-advisory/perspectives/quantum-computers-and-the-bitcoin-blockchain.html
The Risk of Quantum to Classical Cryptography:
https://blog.projecteleven.com/posts/the-risk-of-quantum-to-classical-cryptography
Free E-Book - Quantum Computing for Dummies:
https://github.com/VaradBelwalkar/Books/blob/master/Quantum%20Computing%20For%20Dummies.pdf
Paperback - Quantum Computing for Everyone:
https://www.amazon.co.uk/Quantum-Computing-Everyone-Mit-Press/dp/0262539535
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https://x.com/qdayclock, https://x.com/GoogleQuantumAI, https://x.com/QuantumDaily
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