Computability of discontinuous functions-Towards its paradigm

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In studying computability of some real functions which are discontinuous with respect to the Euclidean metric, the most useful and natural METHOD is uniformization of the domain of a function by isolating the discontinuous points. A general theory of the effective uniform space, especially the space of Fine metric, has been clarified. For the computability problem of a function sequence whose functions have different discontinuity points, a theory of the effective sequence of uniformities and its limit has been developed. Admitting limiting recursive functions in characterizing the image of a computable sequence of elements by a discontinuous function is another theory. In a natural setting, these two theories are equivalent. We can claim that the theory of the effective uniformity (the sequence of effective uniformities) is the fundamental method for the computability of some discontinuous functions. Limiting recursion is equivalent with Sigma^0_1 excluded middle. The relative strength between Sigma^0_1 excluded middle and other semi-constructive principles have been worked out. As for functional analysis, effectivization of various theorems, mainly on the Banach space, has made progress. A representation of real numbers in terms of {0,1,Bottom},characterizing the computability of real numbers has been studied. Some counter-examples have been constructed :a function sequence which is sequentially computable but has no effectively continuous points and a function which is Banach-Mazur computable but is not Markov computable. In applications, dynamics of double rotation maps, description of the inverse problem in multi-sectorial growth theory, the computability problem of fractals with infinitely many contraction maps, reorganization of hardware and software for discovery of non-trivial knots have been studied.