These disturbances can cause some of the information necessary for the computation to leak out of the processor, a situation known as decoherence.
That said, useful computations are possible only on quantum machines with a huge number of qubits, and those do not yet exist. What’s more, qubits and their interactions must be robust against errors introduced through the effects of thermal vibrations, cosmic rays, electromagnetic interference and other sources of noise. These disturbances can cause some of the information necessary for the computation to leak out of the processor, a situation known as decoherence. That can mean dedicating a large proportion of the qubits to error-correction routines that keep a computation on track.