What does quantum physics tell us about computation?

As computers become faster they must become smaller because of the finiteness of the speed of light. If computers are to continue to become smaller, new, quantum technology must replace or supplement what we have now, but it turns out that quantum physics can offer much more than smaller and faster microprocessors. It can support entirely new modes of computation, with new quantum algorithms that do not have classical analogues. Moreover, recent progress in the quantum theory of computation forces us to question the classical view of computation as a purely logical notion independent of that of computation as a physical process. We provide a brief overview of these new developments which may lead to a significant revision of our understanding of the nature of computation.