 Quantum threshold theorem

In quantum computing, the (quantum) threshold theorem (or quantum fault-tolerance theorem), proved by Michael Ben-Or and Dorit Aharonov (along with other groups), states that a quantum computer with a physical error rate below a certain threshold can, through application of quantum error correction schemes, suppress the logical error rate to arbitrarily low levels.Current estimates put the threshold for the surface code on the order of 1%, though estimates range widely and are difficult to calculate due to the exponential difficulty of simulating large quantum systems.