Overview
- Anthropic announced Friday that its Claude Mythos 5 model autonomously designed and refined quantum circuits in a 53-hour STEM Fellows experiment led by Andi Gu.
- Claude improved on published designs in seven of eight benchmark tasks, with a modular inversion circuit using up to 17 times fewer Toffoli-style gates in one variant.
- The 17× gate reduction came with a qubit tradeoff in that variant, using about 12 percent more qubits than the smallest prior design to avoid storing full branching histories.
- The process used a generator–judge loop: Claude proposed circuits from plain-language specs, an automated evaluator checked correctness and scored gate and qubit costs, and designs were validated by simulations and formal proofs in Lean.
- Results are task-limited and hardware-dependent, so gains do not remove the need for better error correction and more robust qubits, but the approach could let researchers explore many more circuit designs and speed engineering choices as hardware improves.