 Another community where many favor the MWI is that of the researchers in quantum information. In quantum computing, the key issue is the parallel processing performed on the same computer; this is very similar to the basic picture of the MWI. Recently the usefulness of the MWI for explaining the speedup of quantum computation has been questioned: Steane 2003, Duwell 2007, Cuffaro 2012, forthcoming. It is not that the quantum computation cannot be understood without the framework of the MWI; rather, it is just easier to think about quantum algorithms as parallel computations performed in parallel worlds, Deutsch and Jozsa 1992. There is no way to use all the information obtained in all parallel computations — the quantum computer algorithm is a method in which the outcomes of all calculations interfere, yielding the desired result. The cluster-state quantum computer also performs parallel computations, although it is harder to see how we get the final result. The criticism follows from identifying the computational worlds with decoherent worlds. A quantum computing process has no decoherence and the preferred basis is chosen to be the computational basis.