Concerns that quantum computing could one day crack Bitcoin’s cryptography have sparked fierce debate across the crypto industry.
But Alex Thorn, head of research at Galaxy Digital (GLXY), said claims that Bitcoin isn’t ready or that investors should avoid exposure as a result are exaggerated.
The risk itself is not imaginary. In theory, a sufficiently advanced quantum computer could obtain the private key from the exposed public key, allowing an attacker to forge signatures and steal funds. But Thorne believes that describing this as a looming or unique Bitcoin crisis ignores key context, both about the technology and the work that has begun to address the problem.
“The risk is real, but it’s also recognized,” Thorne told CoinDesk. “The people best positioned to solve this problem are actively working on it.”
Quantum computing is a fundamentally different approach to computing that uses the principles of quantum mechanics rather than classical physics. Rather than using traditional 0 or 1 bits, quantum computers use “qubits,” which can exist in multiple states at once, a property called superposition that allows them to handle multiple possibilities simultaneously.
Combined with another feature called entanglement, this allows quantum machines to solve certain complex problems more efficiently than classical computers, particularly tasks such as factoring large numbers that are the basis of modern cryptography
Analysis by Project Eleven, a security company focused on quantum risks in digital assets, shows that approximately 7 million Bitcoins Valued at approximately $470 billion at recent prices, they may be vulnerable under the definition of “long-term exposure,” meaning their public keys are already exposed on-chain. Other estimates vary widely depending on how exposure is defined.
Importantly, most Bitcoins today are not immediately vulnerable to attacks. Funds are only at risk if the public key is exposed on-chain, either because users reuse addresses, some custodians use operational shortcuts, or because the tokens are in an old address format. Although some estimates suggest that millions of Bitcoins fall into these categories, they are still secure given the currently known quantum capabilities.
This distinction is at the heart of Galaxy’s argument. The conversation has become polarizing, with some arguing that quantum computing is decades away while others warn of imminent dangers. Thorne’s view lies somewhere in between. The likelihood of future threats is high enough to warrant action, but not so urgent that it exceeds Bitcoin’s ability to respond.
This response is already underway.
There is a growing body of technical work dedicated to making Bitcoin “quantum resistant” over time. One of the most prominent efforts involves the introduction of new address types that rely on post-quantum cryptography. These will enable users to move funds out of potentially vulnerable formats, significantly reducing long-term risk.
“There’s a lot more work being done than people realize,” Thorne said. “Developers are actively building ways to upgrade the system.”
Other proposals address edge cases such as dormant coins with permanently exposed public keys. The idea, sometimes called an “hourglass” approach, would gradually limit how these tokens can be used, mitigating systemic risk without outright confiscation or destruction.
More broadly, developers are exploring staged upgrade paths that would allow Bitcoin to adapt to more extreme scenarios, such as a world where quantum systems could quickly break existing encryption schemes. This could include changing the way transactions display public keys in the first place, thus limiting the attack surface entirely.
While these efforts are complex from both a technical and governance perspective, Thorne emphasized that Bitcoin’s open development model is a strength, not a weakness. The ecosystem has the time, talent, and strong incentives to solve problems before they become serious.
Crucially, the number of actors capable of triggering a so-called “Q-day” – when quantum computers break modern cryptography – remains extremely limited. Even optimistic predictions suggest that only a small group of highly specialized researchers will be able to achieve such a breakthrough in the foreseeable future.
Against this backdrop, Thorne believes the rising tide of quantum-related fear, uncertainty and doubt is disproportionate.
“Quantum computing is a powerful and potentially disruptive technology, but that does not mean that all risks are immediate or uncontrollable,” he said.
For investors, the takeaway is simple. Quantum risk should be monitored, but it cannot be used as a blanket reason to avoid Bitcoin exposure. The network has a track record of evolving in response to credible threats, and the foundation for quantum resilience has been laid.
“It’s not certain that quantum is an existential issue for Bitcoin, but its possibility is cause for concern,” Thorne said. “But what is clear today is that Bitcoin developers are not ignoring it. On the contrary, many are actively working on it,” he added.
Read more: Quantum computing is a long-term risk for Bitcoin, not an imminent threat, says Cathie Wood’s Ark Invest