On The Brink with Castle Island Weekly Roundup 11/21/25 (Quantum FUD, DAT hangover, stablecoin duration risk) (EP.686)
Nov 21, 2025
This week, the hosts dive into the intriguing worries surrounding quantum computing's potential impact on Bitcoin, sparking sell-offs and market panic. They analyze the ongoing effects of a recent flash crash while exploring whether the U.S. government could seize Satoshi's coins amid quantum risk. The guys also discuss stablecoin duration risks and contemplate a possible bailout for AI. Additionally, they touch on institutional Bitcoin holdings and speculate on the future of NFTs. Get ready for a whirlwind of crypto news and debates!
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Episode notes
Quantum Threat Is Near-Term Plausible
- Scott Aaronson now considers a fault-tolerant quantum computer plausible within a few years and that possibility threatens current cryptography.
- Nic Carter and Matt Walsh argue the Bitcoin community must start upgrade conversations now to mitigate existential risk.
Begin Post‑Quantum Testing Now
- Start testing post-quantum signature schemes immediately rather than rushing an unvetted migration.
- Prefer tried-and-true, thoroughly analyzed algorithms and give users years to migrate their keys.
Post‑Quantum Will Change Bitcoin's Shape
- A Bitcoin upgrade to post‑quantum signatures is an enormous infrastructure change, potentially altering address/key formats and block-space needs.
- Nic warns post‑quantum signatures are much larger, implying blocks or capacity must change.
