Alice & Bob affirme que RSA-2048 pourrait tomber avec 22 593 qubits de chat en environ trois jours, 40 fois moins que l'estimation de 2025

Alice & Bob has published a resource estimate for breaking RSA-2048 on its cat qubit architecture: 22,593 physical qubits running for about 3.14 days, and 29,588 physical qubits for about 62 minutes against a 256 bit elliptic curve discrete logarithm. The company says this is roughly 40 times fewer physical qubits than the estimate Google Quantum AI's Craig Gidney published in 2025, which put RSA-2048 under one million superconducting qubits in under a week. The reduction comes from cat qubits that suppress bit flip errors in hardware, so error correction only has to handle phase flips, together with LDPC cat codes and a redesigned adder.

These are theoretical projections rather than a demonstrated attack, and the hardware to run them does not yet exist. The company itself expects hardware progress and falling resource requirements to converge in the early 2030s. The pattern is the one that matters: each year the published estimate for a cryptographically relevant quantum computer gets smaller, and each year less of the assumed runway remains.

Our take

We treat this as a claim, and we note that every serious estimate for the past three years has moved in the same direction. The data at risk was collected last year: anything recorded today under RSA or elliptic curve key exchange is exposed to whichever estimate proves right. Long lived equipment, long lived secrets. The hardware stays, the keys change, and the work starts with an inventory. Start your Discovery Program.