Discovery in Quantum Theory Could Solve Baryon Asymmetry Problem

Quantum theorists looking to solve one of the field's persisting problems found something that benefits other fields of physics instead.

One of the longstanding "errors" in the field of quantum computing is in quantum annealing: in order to operate properly, these computers have to run at a relatively slow rate. While examining the behavior of quantum annealing computers at speeds faster than those required for operation, they found something unexpected - a previously undiscovered phenomenon that could help explain the perceived imbalance between matter and antimatter in the Universe and could also guide a new approach for isolating isotopes.

Qubit Asymmetry Leading to Other Discoveries

"Although our discovery did not cure the annealing time restriction, it brought a class of new physics problems that can now be studied with quantum annealers without requiring they be too slow," shared Nikolai Sinitsyn, a theoretical physicist from the Los Alamos National Laboratory (LANL) and one of the authors of the study. Together with his colleagues and co-authors Bin Yan and Wojciech Zurek, also from LANL, and Vladimir Chernyak from Wayne State University, they led a report appearing in the journal Physical Review Letters.

While the new discovery does not immediately advance quantum computing, it hints at solving other scientific problems.

"We believe that small modifications to recent experiments with quantum annealing of interacting qubits made of ultracold atoms across phase transitions will be sufficient to demonstrate our effect," Sinitsyn added.

Solving the Matter - Antimatter Imbalance

In physics and physical cosmology, this imbalance is known as the baryon asymmetry problem, where there is a large perceived difference between baryonic matter - which refers to those we perceive with our senses in everyday life - and antibaryonic matter, or simply antimatter. Both materials are widely accepted to have been created at the start of the Universe.

Researchers were able to break through the perceived symmetry between matter and antimatter interaction, albeit on a very small scale. It remains unclear how the minute discrepancy translates to larger scales, as in the amount of both materials in the entire Universe.

In the qubit observation, the effect demonstrates physical evidence of an asymmetry between baryonic matter and its antibaryonic counterpart. This asymmetry has been observed when large quantum systems pass through a phase transition or when their quantum states undergo sharp rearrangements. Under this phenomenon, strong but symmetric interactions more or less compensate for each other. However, subtle differences have been found to exist.

Slowing Down Quantum Annealers

Quantum annealing computers are particularly designed for solving complex mathematical and optimization-related problems, associating and storing values in qubits - or quantum bits. Whereas the classical bits in conventional computers only have two states - one and zero - qubits have other values aside from these two, made possible by a phenomenon known as quantum superposition. This allows quantum computers to have potentially exponential computing powers compared to their traditional counterparts.

In operation, these qubits are first prepared in their basic energy state through a strong external magnetic field. The external magnetic field is slowly reduced, eventually turned off, all the while qubit interactions are gradually ramped up.