No Second Best - A Bitcoin Podcast Bitcoin's Quantum Problem: Decades Away or Imminent Danger?
Feb 19, 2026
Brandon Black, a software engineer and Bitcoin developer who implemented Taproot multisig and MuSig2, offers a technical take on quantum threats. He explains Shor's attack, contrasts SHA-256 and ECDSA risks, and discusses address hygiene, qubit scaling challenges, and the timeline for any cryptographic migration.
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Carter's 2028 Projection And Context
- Nick Carter estimated a quantum-capable computer by 2028 and has invested in a quantum defense startup.
- Hurley notes Carter's financial context as relevant to interpreting his timeline claims.
Institutions Are Both Risk And Defense
- Institutional holders have the strongest incentives to prevent quantum compromise and could drive upgrades.
- The same institutions that could pressure change are also motivated to keep Bitcoin secure, aligning incentives toward resilience.
Two Crypto Layers, Two Threat Levels
- SHA-256 faces only a modest quantum speedup via Grover's algorithm and can be mitigated by increasing key size.
- ECDSA faces the real quantum threat because Shor's algorithm could derive private keys from public keys.