Turing's famous 1936 paper introduced a formal definition of a computing machine a Turing machine This model led to both the development of actual computers & to computability theory the study of what machines can & cannot compute This book presents classical computability theory from Turing & Post to current results & methods & their use in studying the information content of algebraic structures models & their relation to Peano arithmetic The author presents the subject as an art to be practiced & an art in the aesthetic sense of inherent beauty which all mathematicians recognize in their subject Part I gives a thorough development of the foundations of computability from the definition of Turing machines up to finite injury priority arguments Key topics include relative computability & computably enumerable sets those which can be effectively listed but not necessarily effectively decided such as the theorems of Peano arithmetic Part II
Includes:: the study of computably open & closed sets of reals & basis & nonbasis theorems for effectively closed sets Part III covers minimal Turing degrees Part IV is an introduction to games & their use in proving theorems Finally Part V offers a short history of computability theory The author has honed the content over decades according to feedback from students lecturers & researchers around the world Most chapters include exercises & the material is carefully structured according to importance & difficulty The book is suitable for advanced undergraduate & graduate students in computer science & mathematics & researchers engaged with computability & mathematical logic