Podcast Episode Summary
Podcast: Unchained
Episode: Q-Day Is Imminent. Can Bitcoin Survive the Quantum Threat?
Host: Laura Shin
Guest: Alex Pruden, CEO & Co-founder, Project 11
Date: January 18, 2026
Episode Overview
This episode investigates the existential threat quantum computing poses to Bitcoin and the wider crypto ecosystem. Laura Shin is joined by Alex Pruden, CEO of Project 11, a company building tools for post-quantum cryptographic infrastructure. They traverse the technical, social, and cultural challenges presented by quantum advances—exploring the realistic timelines for quantum breakthroughs, what Q-Day (i.e., when quantum computers can break modern cryptography) could look like, how different chains and wallet practices stand up to this risk, and what proactive steps can and should be taken—both by protocol developers and asset holders.
Key Discussion Points & Insights
1. What is Quantum Computing and Why Does it Matter for Crypto?
- Definition and Relevance
- Quantum computing utilizes principles of quantum mechanics (superposition and entanglement) to process information in fundamentally different ways than classical computers ([03:18]).
- Shor's Algorithm: Enables efficient factoring of large numbers—a core vulnerability for cryptographic systems.
- Grover's Algorithm: Speeds up brute-force search attacks, but is less threatening for blockchains in the near term ([09:20]).
- Key Quote:
"Bitcoin and all crypto networks rely on broken cryptographic algorithms and quantum computing can break them. Like we know those things. Just a question of when."
— Alex Pruden [06:52]
2. Quantum Timelines—Is the Threat Urgent?
- Estimates from leading quantum physicists vary drastically, from 2–3 years to 30–50 years for cryptographically relevant quantum computers ([04:55]).
- Recent Developments:
- Google’s ‘Willow’ chip demonstrated that the science problem has been solved; now only an engineering challenge remains ([05:47]).
- Growing “bullishness” among quantum experts suggests timelines may accelerate without public warning, likened to the leap in advances seen with AI.
- Key Concern:
- There’s unlikely to be advance public warning; the first use may be clandestine in espionage ([07:57]).
- Key Quote:
"Whoever has the capability really has no incentive to share it right before they use it...as we get closer and closer...I would fully expect us as a public to know less and less about what is the state of the art."
— Alex Pruden [07:57]
3. How Would Quantum Computers Break Bitcoin & Blockchains?
- Asymmetric Cryptography Attack:
- Shor's algorithm breaks ECC, exposing private keys when public keys are visible ([09:20]).
- Bitcoin is unusual in that public keys are not always directly exposed—addresses are usually hashes.
- Vulnerability:
- ~35-40% of all Bitcoin is exposed today—the public keys have been made visible due to address type, repeated spends, or exchange/bridge infrastructure ([13:47], [15:49]).
- Blockchains are uniquely vulnerable due to on-chain permanence and explicit value tied to keys.
- Key Quote:
"That represents arguably the biggest, you know, cyber security honeypot that's ever existed."
— Alex Pruden [13:47]
Follow-up: Bitcoin’s UTXO Model and Public Key Exposure
- Bitcoin’s standard P2PKH (Pay to Public Key Hash) addresses only reveal public keys upon spend, so many coins are never exposed if unused ([14:13]).
- Other protocols (e.g., Ethereum, Solana) expose public keys almost immediately due to account models or address implementations—making them more vulnerable ([15:43], [18:51]).
4. Risks for Other Blockchains: Technical and Cultural Factors
- Technical:
- Bitcoin: Fewer coins exposed, but most value at risk and migration is hard.
- Ethereum: Accounts, not UTXOs; most public keys are exposed.
- Solana: Addresses are raw public keys; 100% of supply is vulnerable ([18:51]).
- Cultural:
- Solana and similar chains may be able to coordinate a response due to centralized foundations.
- Bitcoin has deep decentralization, making coordinated upgrades slow and difficult.
- Migration Challenge:
- No precedent exists; all assets, contracts, wallets, and protocols need “full lift and shift” migrations ([21:42]).
- Key Quote:
"This is by far the biggest effort, the most significant upgrade any of these things will ever undergo...protocols all have to add support for new post quantum cryptography. And there's consequences to that."
— Alex Pruden [18:51]
5. Project 11’s Role and the Path to Quantum Resilience
- Migration Tools:
- Built “Yellow Pages”—a public registry where users can attest control of assets with post-quantum cryptographic signatures, serving as a proof-of-concept bridge between classical and future quantum-safe protocols ([23:15]).
- Major challenge: protocol support is needed, especially in Bitcoin; other chains may enable quantum-secure wallets/contracts sooner ([26:09]).
- Overall Approach:
- Focus on building infrastructure for user asset migration and eventual integration at the protocol layer.
- Need for "cryptographic agility": the ability to rapidly migrate to new schemes if new vulnerabilities are discovered ([28:03]).
- Key Quote:
"There needs to be a new island we all go to...there needs to be a bridge or a path or a migration protocol to get you there."
— Alex Pruden [23:15] "The infrastructure...needs to be what is termed agile. Right. So you need to be able to switch quickly and we need to build in these pathways."
— Alex Pruden [28:03]
6. Unresolved and Contentious Issues: The Case of Satoshi’s Bitcoins
- Est. $150 Billion in Satoshi’s coins have exposed public keys and are prime targets for post-Q-Day theft ([36:03]).
- Dilemmas:
- Let quantum attackers claim the coins.
- Proactively burn the coins.
- Reallocate (e.g., to future mining rewards).
- Potential Fallout:
- Any action (or inaction) could lead to a contentious "civil war" level fork, given the deep philosophical differences in Bitcoin’s community about property rights and code sanctity ([39:03]).
- Key Quotes:
"My personal belief is, unless this is resolved, there will be a fork over these two things because I think these are very different views of what bitcoin should be."
— Alex Pruden [39:03] "[The block size war] will look like child's play compared to this..."
— Laura Shin [39:03]
7. State of Quantum Response in Crypto Ecosystem
- Ethereum:
- Recognizes the threat; plans to integrate quantum resilience into long-term roadmap ([30:16]).
- Solana:
- Engagement is picking up.
- Bitcoin:
- Most decentralized, slowest to adapt, but securing the most value—making lack of action particularly dangerous.
Notable Quotes & Memorable Moments (with Timestamps)
- "There's not a guarantee that this doesn't actually happen sooner than people expect...the possibility that these are decentralized systems that secure an enormous amount of value that entirely rely upon this cryptography, that will be broken." — Alex Pruden [06:52]
- "Whoever has the capability really has no incentive to share it right before they use it…and I would fully expect us as a public to know less and less about what is the state of the art." — Alex Pruden [07:57]
- "That represents arguably the biggest...cyber security honeypot that's ever existed." — Alex Pruden [13:47]
- "Protocols all have to add support for new post quantum cryptography. And there's consequences to that…every asset, every smart contract, every custody solution, it all has to turn over." — Alex Pruden [18:51, 33:50]
- "There will be a fork over these two things because I think these are very different views of what bitcoin should be…this is what you see [in contentious blockchains]." — Alex Pruden [39:03]
- "That will look like child's play compared to this because...the community is even bigger and more diverse with people who have wildly different philosophies involved." — Laura Shin [39:03]
- "At the very least now, by framing the issues, thinking through the implications, having the conversation...is better than just pretending it's not real." — Alex Pruden [39:40]
Important Timestamps
- [03:18] — What is quantum computing? How is it relevant?
- [04:46] — Timelines: How soon is the quantum threat?
- [09:20] — Quantum attack vectors on Bitcoin
- [13:47] — How much Bitcoin is vulnerable? Why not all is at risk
- [15:43] — UTXO model vs account model chain vulnerabilities
- [18:51] — Risk profiles for different blockchains (technical and cultural)
- [21:42] — Scale and unprecedence of the potential migration
- [23:15] — Project 11’s Yellow Pages and vision for quantum-safe migration
- [28:03] — Philosophical issues: How can “quantum-safe” be validated?
- [30:16] — Are any chains better positioned?
- [33:53] — Alex Pruden’s founding story for Project 11
- [36:03] — Satoshi’s coins: Burn, reallocate, or risk quantum theft?
- [39:03] — Cultural and social implications: Bitcoin's future fork?
- [39:40] — Importance of preparing for quantum, rather than denial
Closing Thoughts
This episode is a clarion call for the crypto community, especially Bitcoin stakeholders, to take quantum computing seriously—not just as a speculative threat but an impending reality. The conversation highlights that the problem is both deeply technical and sociopolitical: massive coordinated migrations will be necessary and, for the “big chains,” resolving these questions could spark conflicts surpassing past blockchain governance crises.
For Listeners Who Haven’t Tuned In
If you’re in crypto—developer, holder, or skeptic—this episode makes it clear: quantum computing isn’t science fiction, and ignoring it puts entire market ecosystems at risk. Alex Pruden compellingly outlines why, when, and how all holders must prepare—not just with protocol innovation but also cultural consensus—to cross the Q-Day chasm safely.
