Science is increasingly hungry for computing power, constantly searching for more advanced tools to tackle its questions. The new frontier is quantum computers, devices that leverage the quantum properties of matter, such as superposition and entanglement, to perform highly complex operations.

A research group led by the Department of Physics at the University of Trento had the opportunity to test some hypotheses related to confinement in ℤ2 lattice gauge theory using quantum supercomputers provided by Google’s Quantum Artificial Intelligence Lab in California. The research was published in Nature Physics.

Gauge theories describe the fundamental forces within the standard model of particle physics and play a key role in condensed matter physics. The constituents of gauge theories—such as charged matter and the electric gauge field—are governed by local constraints that lead to key phenomena that remain partially understood. In this context, quantum simulators offer solutions that traditional computers cannot achieve.

"At the end of 2019," explains Philipp Hauke, professor of Theoretical Physics of Fundamental Interactions at UniTrento and corresponding author of the study, "Google launched a call for projects exploring the potential of quantum computers. The University of Trento was among the eight winners globally, the only institution in the entire European Union."

The team led by Professor Hauke chose to work on a question concerning elementary particles, specifically lattice gauge theory, which posits that continuous spacetime is discretized into a typically hypercubic lattice of points. The question focused on how electrons, positrons, and, potentially, quarks and gluons interact to form particles and matter.

The team developed an algorithm that was sent remotely to Google's powerful quantum computers. These supercomputers, located in Santa Barbara, naturally describe quantum objects using the quantum properties of matter—something that classical "bits," based on the binary opposition between 1 and 0, cannot achieve.

The results of the research were published in Nature Physics.