Adam Back, CEO of blockchain infrastructure firm Blockstream, publicly challenged comments by Bitcoin commentator Nick Carter on June 19, disputing claims that quantum computers pose an imminent threat to Bitcoin’s security.
Blockstream CEO Adam Back slams Bitcoiner VC Nic Carter for fueling "uninformed noise" about quantum risks.
Back insists that devs are working on quantum-readiness quietly behind the scenes, without needing to spark public alarm. #Bitcoin pic.twitter.com/voNcvH8zCp
— Conor Kenny (@conorfkenny) December 20, 2025
Responding on X (formerly Twitter), Back criticized Carter’s warnings as “noise driven by a lack of technical understanding,” suggesting they were intended to stir market sentiment rather than reflect realistic risks. Carter has previously disclosed his investment in “Project Eleven,” an initiative focused on developing quantum-resistant cryptographic solutions.
How Real Is the Quantum Threat to Bitcoin?
At the center of the debate is timing, specifically, when quantum computing could realistically compromise Bitcoin’s cryptographic foundations.
Back argued that current quantum computing technology remains highly experimental, with major unresolved physical and engineering challenges. According to him, quantum systems capable of breaking Bitcoin’s encryption do not pose a real risk within the next decade, and any meaningful threat is likely several decades away.
Bitcoiners are in denial about quantum risk so they are accusing me of a conflict of interest.
– Yes CIV invested in Project 11 @qdayclock – more to come on that soon
– This has been clearly disclosed on the Castle Island portfolio page (https://t.co/Q98Lc7TpUd) since we made… pic.twitter.com/lPE3OxU0SK— nic carter (@nic_carter) December 19, 2025
Carter, however, has taken a more urgent stance. He has criticized what he describes as an overly dismissive attitude among Bitcoin developers, arguing that governments are already preparing for a post-quantum era. He warned that Bitcoin could become an attractive “bug bounty–style target” for quantum researchers once capabilities advance.
The concern is not limited to Bitcoin alone. Other major cryptocurrencies, including Ethereum (ETH), rely on similar cryptographic primitives and could face comparable long-term challenges.
Industry Reactions and Diverging Views
The broader crypto industry remains divided. Charles Edwards, founder of Capriole Investments, has suggested that quantum-related risks could materialize within two to nine years, depending on breakthroughs in quantum hardware.
In contrast, prominent Bitcoin advocates such as Michael Saylor have dismissed such timelines as exaggerated, arguing that fears are being overstated relative to the actual state of technology.
Back emphasized that the Bitcoin community understands the necessary mitigation strategies and is actively researching long-term solutions without resorting to panic. He reiterated that no existing quantum computer today is capable of breaking Bitcoin’s cryptography, according to current expert consensus.
While both sides agree on the importance of continued research into post-quantum security, they differ sharply on urgency and how the issue should be communicated to investors and the public.
Implications for Investors
As the debate continues, investors are being encouraged to reassess portfolio-wide risk management rather than focus solely on speculative quantum threats. For now, the consensus among many cryptography experts is that quantum computing remains a long-term consideration, not an immediate existential risk to Bitcoin or the broader crypto market.
