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The Turing machine, an abstract computer conceived half a century ago as a test of what might be computable, has been overtaken by an idealized quantum computer, which also has drawbacks.
Recent data on the comparative scientific performance of different nations suggest that the decline in British basic science apparent during the 1970s began to level off at the start of the 1980s. However, rather than heralding the beginning of a revival, the evidence suggests that this is merely a temporary halt to the long-term slide.
