QUANTUM COMPUTING AND BLOCKCHAINS

Summary from the TLDR Crypto newsletter

While post-quantum encryption requires immediate deployment due to harvest-now-decrypt-later attacks already underway, blockchains face less urgent timelines for post-quantum signatures since they aren't vulnerable to HNDL and cryptographically relevant quantum computers remain 10+ years away. Most public blockchains like Bitcoin and Ethereum use signatures rather than encryption and thus aren't exposed to current HNDL risks, though privacy chains that encrypt transaction details face immediate vulnerability. Bitcoin presents unique challenges, including slow governance processes and hundreds of billions in abandoned quantum-vulnerable coins, but blockchains should prioritize implementation security over quantum threats in the near term while beginning migration planning.