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hours by 2010 [Coles et al., 2006]. To handle this flood of information efficiently it
will need to be met with a continuing dramatic increase in information processing
power.
1.1.2 Moore’s Law
For the past 40 years, the performance of computing devices has doubled
roughly every 18 months. This trend is commonly referred to as “Moore’s Law”,
inspired by an article written in 1965 by Intel co-founder Gordon Moore [Moore,
1965]. Despite the fact that Moore’s Law is expected to hold for at least another
decade, it is important to prepare for the longer term future when transistors on
silicon will have been pushed to their limits.
1.1.3 Church-Turing Thesis
The Church-Turing Thesis makes this even more pressing. Alan Turing in 1938
described a universal logic machine [Turing, 1938] that can efficiently, i.e. in polynomial
time, simulate any other computing system. This logic machine is simple
enough to allow any classical computer to simulate it efficiently as well. Therefore,
any classical computer can simulate any other computing system efficiently. This
implies that problems that are intractable, i.e. not solvable in polynomial time,
on current computers will remain intractable on all future computers. Examples
2