Watch Out Bitcoin: Cryptography-Breaking Quantum Computers May Be Closer Than Expected, Says Caltech

New research from the California Institute of Technology (Caltech) suggests that quantum computers capable of breaking modern cryptography might require significantly fewer qubits than previously estimated. The study, conducted in collaboration with quantum computing startup Oratomic, outlines a novel error-correction approach for neutral-atom quantum computers that could accelerate the development of machines powerful enough to run Shor’s algorithm.

Key Developments in Quantum Computing

The Caltech and Oratomic research proposes a neutral-atom system where atoms are controlled by lasers to act as qubits. This method could enable a fault-tolerant quantum computer to execute Shor’s algorithm using as few as 10,000 reconfigurable atomic qubits. This is a substantial reduction from earlier estimates, which often cited up to a billion qubits.

Dolev Bluvstein, co-founder and CEO of Oratomic, highlighted the rapid progress in quantum computing. He noted that while quantum computers were once considered a decade away, the best estimates for running Shor’s algorithm have drastically decreased from one billion qubits to potentially 10,000, especially considering the advancements in lab systems that now approach or exceed 6,000 physical qubits.

Implications for Cryptography and Security

The advance could hasten the arrival of quantum computers capable of deriving private keys from public keys used in widely adopted cryptography, such as Bitcoin's elliptic-curve cryptography. This development increases the urgency for migrating to quantum-resistant cryptography.

Current error-correction systems typically require approximately 1,000 physical qubits for a single logical qubit, pushing estimates for practical fault-tolerant systems into the millions. However, the new neutral-atom approach appears to reduce this overhead significantly. Bluvstein mentioned that achieving 10,000 physical qubits could be feasible within a year, though building a functional quantum computer remains a complex engineering challenge.

This research follows recent findings from Google researchers, also suggesting that future quantum computers could break elliptic curve cryptography with fewer resources than anticipated. Bluvstein emphasized that the threat posed by quantum computers extends beyond blockchain networks to encompass the entire global digital infrastructure, including IoT devices, internet communication, routers, and satellites.

Despite the engineering hurdles, Bluvstein believes a practical quantum computer could emerge before the end of the decade, underscoring the need for a broad transition to post-quantum cryptography across various sectors.