Quantum-Computing

In 1935, Schrödinger introduced the cat as a reductio ad absurdum of quantum superposition. Ninety years later, “cat states” — superpositions of coherent states with opposite phases — are a practical tool in quantum computing. Bosonic cat qubits have bit-flip times exceeding minutes, scaling exponentially with photon number, and are among the leading architectures for fault-tolerant quantum computation. The cat is no longer a paradox. It is a qubit.

In December 2024, Google published a Nature paper announcing that their Willow chip demonstrated quantum error correction below the threshold — the point at which larger codes become more reliable, not less. The headline about “10^25 years of classical computation” was technically true and mostly a distraction. The real result is more important and less flashy: for the first time, a quantum processor demonstrated that logical error rates decrease exponentially as the code grows. This is what scalable quantum computing looks like at its first credible step.