Classic simulation of hundreds of qubits challenges quantum supremacy

Published on May 26, 2026 | Translated from Spanish

A team of researchers has managed to simulate a quantum system of hundreds of qubits on classical computers using tensor networks, contradicting a 2025 study that claimed only quantum hardware could perform such a task. The work, published in Science, demonstrates that efficient algorithms on traditional machines can replicate these results, opening new avenues for research without relying on specialized equipment.

photorealistic technical illustration of a classical supercomputer cluster simulating quantum circuits, glowing tensor network pathways connecting hundreds of abstract qubit nodes across multiple server racks, processors actively calculating while red indicator lights flash, data cables transmitting information between computational units, central holographic display showing complex quantum state evolution being replicated by classical algorithms, researchers monitoring the process in background, metallic server chassis with cooling vents, blue and orange energy streams representing data flow, dramatic low-angle lighting emphasizing computational power, cinematic engineering visualization with precise geometric details

Tensor networks: the classical Trojan horse in quantum territory 🧠

The key to the breakthrough lies in tensor networks, a mathematical tool that allows representing complex quantum systems through compact data structures. The researchers optimized these tensors to capture the correlation between qubits without exploding in exponential size. Thus, they managed to run simulations previously considered exclusive to quantum prototypes, using conventional classical hardware. The method not only replicates results but also offers a platform for testing quantum algorithms without expensive equipment.

Spoiler: your old PC can also do quantum things (with a catch) 😅

While the defenders of quantum supremacy were rubbing their hands together with their 2025 study, this team comes along and tells them: Relax, with a good algorithm and an office PC, you can do it too. It's like you bought an F1 car to go around the corner and discover that your bicycle gets there first, just with more effort. The moral: before investing in a nuclear reactor, make sure you can't do the same with a calculator and a lot of patience.