IBM has managed to dramatically reduce the number of quantum bits, or qubits, required to prevent errors in a quantum computer. Its latest approach to quantum error correction should bring down the number of qubits needed to build a useful quantum machine.
The biggest problem with today’s quantum computers is that they are noisy, meaning they have error rates around 1 in 1000, whereas classical error rates tend to be around 1 in 1 billion billion. …