Google achieved the world's first "verifiable Quantum Supremacy," setting another milestone in quantum computing. Quantum Supremacy refers to the ability of a quantum computer to solve problems that conventional supercomputers cannot solve within a realistic time.
On the 22nd (local time), Google said it achieved this result through the algorithm "Quantum Echoes," implemented with its in-house quantum chip Willow. The study was published the same day in the international journal Nature.
Conventional computers represent the absence or presence of an electron as 0 and 1, that is, in units of 1 bit. By contrast, the unit of a quantum computer is the Qubit, in which the states 0 and 1 are superposed. If a general computer has 2 bits, it becomes one of four states—00, 01, 10, 11—but 2 Qubits can realize all four simultaneously. If there are 300 Qubits, 2 to the 300th power states—more than the number of atoms in the universe—are possible, drastically boosting computing power.
Google had already said last year that Willow performed in 5 minutes a calculation that would take Frontier, the fastest supercomputer, 10 to the 24th power years (10 septillion years). This time, the key is that the capability has advanced to a level that can be verified.
According to Google, Quantum Echoes showed a computation speed 13,000 times faster than the classical algorithm run by the world's highest-performing supercomputer. In particular, this algorithm is significant in that it secured verifiability that allows the results to be reproduced on other quantum systems.
When Google first announced in 2019 that it had achieved Quantum Supremacy, there was the limitation that it could not be verified, but this time it emphasized that it accurately reproduced the data with an error rate below 0.1%. Google added that it secured the results through a verification test equivalent to 10 researchers testing for one year and more than 1 trillion measurements.
Google said the study goes beyond a simple theoretical achievement and suggests the potential for real-world applications in areas such as new drug development, new materials research, and fusion energy. It is expected to open a path to solving hard problems that conventional supercomputers have not been able to crack in drug discovery, batteries, and new materials design.
Google said, "Within the next five years, real application cases that are only possible with quantum computers will emerge," adding, "We will scale up to large-scale error-corrected quantum computers and maximize practicality."
Kwon Seok-jun, a professor in the School of Chemical Engineering at Sungkyunkwan University, said, "It is significant in that it signals a shift in direction from the physical Qubit scale-up trend that companies like Google and IBM have been competing in," adding, "Based on this, it can also be expected that Google will concentrate more research and development resources not only on expanding physical Qubits going forward, but also on more fundamental issues—namely, the practical efficiency of quantum error correction."
References
Nature (2025), DOI: https://doi.org/10.1038/s41586-025-09526-6