Ebook: Computability Theory. An Introduction

This book introduces the major concepts, constructions, and theorems of the elementary theory of computability of recursive functions. It emphasizes the concept of "effective process" early in order to provide a clear, intuitive understanding of effective computability (as related to functions and sets) before proceeding to the rigorous portion of the book. Subsequent chapters present a formal development of the equivalence of Turing machine computability, enumerability, and decidability with other formulations of the concepts, including systems of recursion equations and post's production systems