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Science
Mathematics
Foundations
Foundations
Mathematical logic
Set theory
Axiomatic systems
Computability theory
Model theory
Category theory
Adjoint functors
Relationship between two functors abstracting many common constructions
Aleph number
Infinite cardinal number
Amalgamation property
Property of a class of models in universal algebra and model theory
Analytical hierarchy
Concept in mathematical logic and set theory
Arithmetical hierarchy
Hierarchy of complexity classes for formulas defining sets
Atomic formula
Mathematical logic concept
Axiom
Statement that is taken to be true
Axiom of choice
Axiom of set theory
Axiom of extensionality
Concept of axiomatic set theory.
Axiom of infinity
Axiom of the Zermelo-Fraenkel set theory
Axiom of pairing
Concept in axiomatic set theory
Axiom of power set
Concept in axiomatic set theory
Axiom of regularity
Axiom of set theory
Axiom of union
Concept in axiomatic set theory
Axiom schema
A formula in the metalanguage of an axiomatic system in which one or more schematic variables appear
Axiom schema of replacement
Concept in set theory
Axiom schema of specification
Concept in axiomatic set theory
Axiomatic system
Mathematical term; concerning axioms used to derive theorems
Banach–Tarski paradox
Taking apart an object and constructing two identical copies of it from the pieces
Binary relation
Relationship between two sets, defined by a set of ordered pairs
Boolean algebra
Manipulation of variables taking only "true" and "false" as values
Cantor's diagonal argument
Proof in set theory
Cantor's theorem
Theorem in set theory
Cardinality
Size of a set in mathematics
Cardinality of the continuum
Cardinality of the set of real numbers
Cartesian closed category
Type of category in category theory
Cartesian product
Mathematical set formed from two given sets
Church–Turing thesis
Thesis on the nature of computability
Class (set theory)
Collection of sets in mathematics that can be defined based on a property of its members
Combinatory logic
Logical formalism using combinators instead of variables
Comma category
Mathematics construct
Commutative diagram
Collection of maps which give the same result
Compactness theorem
Theorem
Complement (set theory)
Set theory concept
Computability theory
Branch of mathematical logic, computer science, and the theory of computation studying computable functions and Turing degrees
Computable function
Mathematical function that can be computed by a program
Computable set
Set where an algorithm can take a number as an input and can decide whether the number belongs to the set
Computably enumerable set
Mathematical logic concept
Computably inseparable
Concept in computability theory
Concrete category
Category equipped with a faithful functor to the category of sets
Continuum hypothesis
Proposition in mathematical logic
Contraposition
Inference that says that a conditional statement is logically equivalent to its contrapositive
Coproduct
Category-theoretic construction
Decision problem
Yes/no problem in computer science
Element (mathematics)
Any one of the distinct objects that make up a set in set theory
Elementary equivalence
Concept in model theory
Empty set
Mathematical set containing no elements
Entscheidungsproblem
Impossible task in computing
Equivalence relation
Mathematical concept for comparing objects
Existential quantification
Logical quantification stating that a statement holds for at least one object
First-order logic
Type of logical system
Five lemma
Lemma in category theory about commutative diagrams
Forcing (mathematics)
Technique invented by Paul Cohen for proving consistency and independence results
Forgetful functor
Drops some or all of the input's structure or properties
Foundations of mathematics
Study of the basic mathematical concepts
Free object
Value of a left adjoint functor to a forgetful functor
Free variables and bound variables
Classification of variables in a logic formula based on whether or not they are inside the scope of a quantifier
Functor
Mapping between categories in mathematical category theory
General recursive function
One of several equivalent definitions of a computable function
Gödel numbering
Function in mathematical logic
Gödel's completeness theorem
Fundamental theorem in mathematical logic
Gödel's incompleteness theorems
Limitative results in mathematical logic
Halting problem
Problem of determining whether a given program will finish running or continue forever
Higher-order logic
Form of predicate logic that is distinguished from first-order logic by additional quantifiers and, sometimes, stronger semantics
Hilbert's axioms
Formal system
Hom functor
Functor mapping hom objects to an underlying category
If and only if
Logical connective
Indexed family
Collection of objects, each associated with an element from some index set
Initial and terminal objects
Special objects used in (mathematical) category theory
Interpretation (model theory)
Concept in model theory
Intersection (set theory)
Concept in mathematics specific to the field of set theory
Intuitionistic logic
Various systems of symbolic logic
Kan extension
Category theory constructs
Karnaugh map
Graphical method to simplify Boolean expressions
Lambda calculus
Formal mathematical logic system centered on function abstractions and applications
Limit (category theory)
Terminology used in theoretical mathematics involving categories.
Logical connective
Symbol connecting sentential formulas in logic
Löwenheim–Skolem theorem
Mathematical theorem
Many-one reduction
Type of Turing reduction
Material conditional
Logical connective
Mathematical induction
Form of mathematical proof
Mathematical logic
Subfield of mathematics
Model complete theory
Concept in model theory
Model of computation
Mathematical model describing how an output of a function is computed given an input
Model theory
Area of mathematical logic
Modus ponens
Rule of logical inference
Modus tollens
Rule of logical inference
Monad (category theory)
Operation in algebra and mathematics
Morphism
Map (arrow) between two objects of a category
Multiset
Mathematical set with repetitions allowed
Naive set theory
Informal set theories
Natural transformation
Central object of study in category theory
New Foundations
Axiomatic set theory devised by W.V.O. Quine
Nine lemma
Category theory lemma about commutative diagrams
Opposite category
Category constructed from another category C, whose objects are the same as those of C, whose morphisms from X to Y are the same as the morphisms in C from Y to X
Oracle machine
Abstract machine used to study decision problems
Ordered pair
Pair of mathematical objects
Ordinal number
Order type of a well-ordered set
Partition of a set
Mathematical ways to group elements of a set
Peano axioms
Axioms for the natural numbers
Pointed set
A set equipped with a choice of a specific element
Post's theorem
Theorem in computability theory
Power set
Mathematical set containing all subsets of a given set
Prenex normal form
First-order formula consisting of a string of quantifiers and bound variables followed by a quantifier-free part
Primitive recursive function
Function that can be computed with loops of bounded length
Principle of explosion
Theorem which states that any statement can be proven from a contradiction
Product (category theory)
Generalized object in category theory
Proof by contradiction
Form of indirect proof that establishes the truth or validity of a proposition
Propositional calculus
Logical study of propositions (whether they are true or false) that are formed by other propositions with the use of logical connectives
Pullback (category theory)
Most general completion of a commutative square given two morphisms with same codomain
Pushout (category theory)
Category-theoretic colimit of a diagram of the form 𝑋←𝑍→𝑌
Quantifier (logic)
Mathematical use of "for all" and "there exists"
Quantifier elimination
Technique to simplify formulas
Reduct
Omission of operations and relations of a structure
Reflexive relation
A binary relation over a set in which every element is related to itself
Rice's theorem
Theorem in computability theory
Rule of inference
Method of deriving conclusions
Russell's paradox
Paradox in the foundations of mathematics
Saturated model
Model for mathematical theories
Set (mathematics)
Collection of mathematical objects
Set theory
Branch of mathematics that studies sets
Sheffer stroke
Logical operation
Signature (logic)
Description of non-logical symbols
Skolem normal form
Formalism of first-order logic
Skolem's paradox
Mathematical logic concept
Snake lemma
Tool used in mathematics
Stable theory
Concerned with the notion of stability in model theory
Structure (mathematical logic)
Mapping of mathematical formulas to a particular meaning, in universal algebra and in model theory
Subcategory
Category whose objects and morphisms are inside a bigger category
Subset
Mathematical set contained in another set
Symmetric relation
Type of binary relation
Tarski's axioms
First-order axiomatization of a fragment of Euclidean geometry
Theory (mathematical logic)
Set of sentences in a formal language
Transfer principle
That all statements of some language that are true for some structure are true for another structure
Transfinite induction
Mathematical concept
Transitive relation
Type of binary relation
Truth table
Mathematical table used in logic
Tuple
Finite ordered list of elements
Turing degree
Measurement for the level of algorithmic unsolvability of a set
Turing machine
Computation model defining an abstract machine
Turing reduction
Concept in computability theory
Turing's proof
Proof by Alan Turing
Type (model theory)
Term in model theory and related areas of mathematics
Type theory
Concept in mathematical logic
Ultraproduct
Mathematical construction
Union (set theory)
Mathematical operation where sets combine or relate
Universal property
Central object of study in category theory
Universal quantification
Mathematical use of "for all"
Universal Turing machine
Type of Turing machine
Universe (mathematics)
Collection that contains all the entities one wishes to consider in a given situation in mathematics
UTM theorem
Affirms the existence of a computable universal function
Venn diagram
Diagram that shows all possible logical relations between a collection of sets
Von Neumann universe
Set theory concept
Well-formed formula
Finite sequence of symbols from a given alphabet that is part of a formal language
Well-ordering theorem
Theoretic principle in mathematics stating every set can be well-ordered.
Yoneda lemma
Theorem in category theory
Zermelo–Fraenkel set theory
Standard system of axiomatic set theory
Zorn's lemma
Mathematical proposition equivalent to the axiom of choice
μ operator
Concept in computability theory