Quantum Computers and Blockchain: A Race Against Time

Charles Hoskinson shares insights on the quantum computing threat to blockchain, emphasizing timing as the main challenge.

Existing Solutions vs. Timing Issues

• Post-quantum standards released by the U.S. National Institute of Standards and Technology (2024).
• Potential inefficiencies in new protocols could slow down blockchain throughput.

When Will Quantum Computers Be a Threat?

• Debate ongoing: Estimates range from a few years to over a decade.
• DARPA's Quantum Benchmarking Initiative aims to assess utility-scale quantum computing by 2033.

Vulnerabilities in Major Blockchains

• Bitcoin, Ethereum, Solana use elliptic-curve cryptography, vulnerable to Shor's algorithm.
• Two main approaches to mitigate risk:
  1. Hash-based cryptography (simple, conservative, mainly for signing).
  2. Lattice-based cryptography (supports advanced tools, better for post-quantum world).

Staged Mitigation Approach

• No immediate switch to one method.
• Post-quantum-signed checkpoints for Cardano's ledger using Mithril and Midnight sidechain.
• Trade-offs:
• Moving from instant finality to probabilistic finality (long-term consequences).