Skip to main content

2024 | Buch

An Invitation to Mathematical Logic

insite
SUCHEN

Über dieses Buch

In addition to covering the essentials, the author’s intention in writing this text is to entice the reader to further study mathematical logic. There is no current “standard text” for a first graduate course in mathematical logic and this book will fill that gap. While there is more material than could be covered in a traditional one semester course, an instructor can cover the basics and still have the flexibility to choose several weeks’ worth of interesting advanced topics that have been introduced. The text can and will be used by people in various courses with different sorts of perspectives. This versatility is one of the many appealing aspects of this book. A list of suggested portions to be covered in a single course is provided as well as a useful chart which maps chapter dependencies. Additionally, a motivated student will have ample material for further reading.

New definitions, formalism, and syntax have been streamlined to engage thereader quickly into the heart of logic and to more sophisticated topics. Part I and Part IV center on foundational questions, while Part III establishes the fundamentals of computability. Part II develops model theory, highlighting the model theory of the fields of real and complex numbers. The interplay between logic and other areas of mathematics, notably algebra, number theory, and combinatorics, are illustrated in Chapters 5, 6, 8, 14, and 16. For most of the text, the only prerequisite is mathematical maturity. The material should be accessible to first year graduate students or advanced undergraduates in mathematics, graduate students in philosophy with a solid math background, or students in computer science who want a mathematical introduction to logic. Prior exposure to logic is helpful but not assumed.

Inhaltsverzeichnis

Frontmatter

Truth and Proof

Frontmatter
Chapter 1. Languages, Structures, and Theories
Abstract
We introduce the fundamental concepts of mathematical logic: languages, structures, satisfaction, theories, logical consequences, and definable sets.
David Marker
Chapter 2. Embeddings and Substructures
Abstract
We study embeddings of structures and how the truth of formulas is preserved under embeddings. Elementary embeddings are introduced and the Tarski–Vaught test for elementary embeddings and the Downward Löwenheim–Skolem Theorem are proved.
David Marker
Chapter 3. Formal Proofs
Abstract
A formal proof system is introduced and deductions in this system are studied.
David Marker
Chapter 4. Gödel’s Completeness Theorem
Abstract
Using the ideas of Henkin, Gödel’s Completeness Theorem is proved, showing that our proof system completely captures the notion of logical consequence.
David Marker

Elements of Model Theory

Frontmatter
Chapter 5. Compactness and Complete Theories
Abstract
The Compactness theorem and some of its consequences are studied. The Upward Löwenheim–Skolem is proved and used to deduce Vaught’s result on the completeness of categorical theories. We show that the full theory of the field of complex numbers is axiomatized as the theory of algebraically closed fields of characteristic zero and give several consequences. Countable categoricity allows us to study dense linear orders and random graphs.
David Marker
Chapter 6. Ultraproducts
Abstract
The ultraproduct construction is introduced and used to give an alternative proof of the Compactness Theorem.
David Marker
Chapter 7. Quantifier Elimination
Abstract
A test for eliminating quantifiers is given and applied it to further study the model theory of algebraically closed fields.
David Marker
Chapter 8. Model Theory of the Real Field
Abstract
We study the model theory of the real field, proving Tarski’s quantifier elimination and decidability results and studying its consequences. We include a brief discussion on more recent work on o-minimal expansions of the real field and exponentiation.
David Marker

Computability

Frontmatter
Chapter 9. Models of Computation
Abstract
Register machines are introduced as a machine-based model of computation. We show that register machines compute exactly the class of general recursive functions and formulate the Church–Turing thesis that this is exactly the collection of computable functions.
David Marker
Chapter 10. Universal Machines and Undecidability
Abstract
Turing’s universal machine is constructed and used to prove the undecidability of the Halting Problem and the undecidability of validity in first-order logic. We include a brief discussion of the Recursion Theorem.
David Marker
Chapter 11. Computably Enumerable and Arithmetic Sets
Abstract
We introduce the computably enumerable sets and the arithmetic sets and show that the form a hierarchy. These results, and the existence of computably inseparable computably enumerably sets, will be used in our approach to the Incompleteness Theorem. We briefly study Kolmogorov randomness as another avatar of incompleteness phenomena.
David Marker
Chapter 12. Turing Reducibility
Abstract
Turing reducibility is introduced as a notion of relative complexity and we study the relationship between the arithmetic hierarchy and the jump operator. Several advanced constructions in computability are surveyed, including the construction of incomparable sets, minimal degrees, and an incomplete non-computable computably enumerable set.
David Marker

Arithmetic and Incompleteness

Frontmatter
Chapter 13. Gödel’s Incompleteness Theorems
Abstract
Gödel’s Incompleteness Theorems are proved. We show that the sets definable in the natural numbers are exactly the arithmetic sets. The Arithmetized Completeness Theorem is used to give an alternative proof of the Second Incompleteness Theorem.
David Marker
Chapter 14. Hilbert’s Tenth Problem
Abstract
We discus parts of the negative solution to Hilbert’s tenth Problem, showing that there is no algorithm to decide if a Diophantine equation has an integer solution.
David Marker
Chapter 15. Peano Arithmetic and
Abstract
We bound the growth rate of computable functions provably total in Peano Arithmetic. This is applied to show the independence of Goodstein’s number theoretic result. Proof theoretic methods, including cut-elimination, are introduced to prove the main result.
David Marker
Chapter 16. Models of Arithmetic and Independence Results
Abstract
The Paris–Harrington variant of Ramsey’s Theorem is proved independent of Peano Arithmetic by model theoretic methods. As a warm-up, we give model theoretic arguments bounding the growth rates of provably total computable functions in weak fragments of arithmetic. We conclude with a brief survey of some of the core results on models of arithmetic.
David Marker
Backmatter
Metadaten
Titel
An Invitation to Mathematical Logic
verfasst von
David Marker
Copyright-Jahr
2024
Electronic ISBN
978-3-031-55368-4
Print ISBN
978-3-031-55367-7
DOI
https://doi.org/10.1007/978-3-031-55368-4

Premium Partner