Concepts from gauge theory could lead to a more efficient way to perform fault-tolerant quantum computation by reducing the number of qubits required for key operations – according to work done by Dominic Williamson and Theodore Yoder at IBM Quantum in the US. By adapting ideas from gauge theory, the researchers show how quantum information spread-out across a machine can be measured using only local checks, significantly lowering computing overhead. Their approach works for a wide class of quantum error-correction codes and could help accelerate the development of practical quantum computers. One importance difference between quantum computers and ordinary computers is how information is stored. Instead of bits, which can be either 0 or 1, quantum computers use qubits, which can exist in a combination of both states at once. Qubits can also be entangled and it is these and other quantum effects that can be harnessed to solve some problems much fast than conventional computers.…