Is the quantum computer capable of cracking Bitcoin starting to take action? Nvidia-backed PsiQuantum aims to go commercial next year.

PsiQuantum’s million-qubit quantum facility in Chicago is under construction, expected to be operational around 2028. Is this a bigger threat to Bitcoin?
(Background: The quantum computer prelude! Vitalik unveils Ethereum’s full quantum resistance roadmap: tackling four major vulnerabilities one by one)
(Additional context: Quantum computing won’t kill cryptocurrencies; it will make them stronger)

Table of Contents

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• How real is the quantum threat?
• Physical qubits ≠ Logical qubits
• Research progress is accelerating
• How the Bitcoin community is responding

PsiQuantum co-founder Peter Shadbolt posted a photo of the Chicago site on X last night, announcing that the world’s first million-qubit quantum computer is under construction, reigniting discussions about whether it can crack Bitcoin’s encryption.

Time to build really big quantum computers. Five hundred tons of steel up in six days. Cryoplant delivery date breathing down our neck. Grateful to the many hundreds of people locked in to this mission pic.twitter.com/eqSwsESusK

— Pete Shadbolt (@PeteShadbolt) March 5, 2026

Funding-wise, in September 2025, PsiQuantum completed a $1 billion funding round led by NVIDIA’s NVentures. Combined with Illinois’ $850 million tax incentives, $500 million state grants, and Blue Owl Capital’s $75 million, total public-private investment exceeded $1 billion.

Technologically, PsiQuantum is betting on silicon photonics, using GlobalFoundries’ Omega chip set based on standard semiconductor manufacturing. The goal is fault-tolerant quantum computing, meaning the system can operate correctly even with errors during computation.

How real is the quantum threat?

Theoretically, quantum computers could use Shor’s algorithm to crack ECDSA and Schnorr signatures used by Bitcoin.

The most vulnerable addresses are “Satoshi-era” P2PK addresses, where the public key is directly exposed on the blockchain. Modern Bitcoin address formats like P2PKH, P2SH, and Taproot protect the public key until spent, making exposure much less likely. In other words, unless you spend those coins, attackers can’t even access your public key.

According to CoinShares research, about 10,230 Bitcoin—worth roughly $728 million—are vulnerable to quantum attacks. CoinShares believes that even if these coins are sold off, the impact would be similar to routine trading and unlikely to cause systemic market disruption.

Physical qubits ≠ Logical qubits

More critically, there’s the computational threshold. Breaking Bitcoin’s signatures would require roughly 2,330 logical qubits, but current systems only have about 100 physical qubits, and none reliably function as logical qubits for cryptographic attacks.

Because qubits are extremely fragile and error-prone, approximately 1,000 physical qubits are needed to produce one reliable logical qubit.

Therefore, with 1 million physical qubits and current error correction techniques, only about 1,000 logical qubits can be generated—still short of the 2,330 needed.

Research progress is accelerating

However, Google AI researcher Craig Gidney’s latest paper shows that the quantum resources needed to break widely used RSA encryption could be 20 times less than previously thought. He estimates that a quantum computer with fewer than 1 million noisy qubits could factor a 2048-bit RSA integer in less than a week—down from his 2019 estimate of 20 million qubits.

While Bitcoin uses elliptic curve cryptography (ECC) rather than RSA, ECC can also be broken by Shor’s algorithm, and the trend of improved efficiency likely applies to both.

How the Bitcoin community is responding

Good news: Bitcoin developers have proposed multiple solutions to enhance quantum resistance. The most well-known is BIP-360, which introduces a new address type allowing Taproot addresses to be immune to remote attacks. Additionally, the U.S. National Institute of Standards and Technology (NIST) has approved three post-quantum signature schemes.

It’s also worth noting that the Federal Reserve’s research warns of the “harvesting and decrypting” risk—attackers could collect encrypted data now and decrypt it later when quantum computers are available. Since Bitcoin’s transaction history is public and permanent, this creates a risk of irreversible exposure of historical data.

In summary, the quantum threat to Bitcoin is more like a manageable upgrade than an imminent apocalypse. There is ample time to observe, plan, and deploy defenses. However, as error correction and algorithms continue to improve, industry experts believe the mid-2030s may be a critical window to take serious action.