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Constructive analysis, types and exact real numbers

  • HERMAN GEUVERS (a1), MILAD NIQUI (a1), BAS SPITTERS (a1) and FREEK WIEDIJK (a1)
Abstract

In this paper we will discuss various aspects of computable/constructive analysis, namely semantics, proofs and computations. We will present some of the problems and solutions of exact real arithmetic varying from concrete implementations, representation and algorithms to various models for real computation. We then put these models in a uniform framework using realisability, which opens the door to the use of type theoretic and coalgebraic constructions both in computing and reasoning about these computations. We will indicate that it is often natural to use constructive logic to reason about these computations.

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