(PhysicsWorld) A new and very efficient protocol for assessing the correctness of quantum computations has been created by researchers at the University of Warwick. The conventional way of checking quantum computations is to do the calculation on a conventional computer and then compare the results. While this is possible for simple computations, even the most powerful supercomputers will not be able to check the work of future quantum computers. Indeed, using huge amounts of conventional computing power to do this defeats the purpose of developing quantum computers.
The team is now collaborating with experimental physicists to evaluate the protocol on nascent quantum processors.
Quantum Computations Disrupted by Environmental Noise
Quantum computations can easily be disrupted by environmental noise, which destroys quantum information in a process called decoherence. As a result, it is crucial to ensure that a quantum computer has done the required calculation and has not fallen prey to decoherence.