Search Results: Undecidable language


Undecidable problem
Selasa, 2026-05-19 20:03:12

In computability theory and computational complexity theory, an undecidable problem is a decision problem for which it is proved to be impossible to construct...

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Undecidable
Senin, 2019-03-04 04:48:41

Look up undecidable or undecidability in Wiktionary, the free dictionary. Undecidable may refer to: Undecidable problem in computer science and mathematical...

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List of undecidable problems
Kamis, 2025-10-02 10:15:31

In computability theory, an undecidable problem is a decision problem for which an effective method (algorithm) to derive the correct answer does not...

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Decidability (logic)
Kamis, 2025-12-04 00:25:35

arbitrary formulas are included in the theory. Many important problems are undecidable, that is, it has been proven that no effective method for determining...

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Gödel's incompleteness theorems
Selasa, 2026-05-19 20:06:12

word undecidable, the term independent is sometimes used instead of undecidable for the "neither provable nor refutable" sense. Undecidability of a statement...

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Algorithm
Minggu, 2026-06-07 09:44:50

JSTOR 2371045. Reprinted in The Undecidable, p. 89ff. The first expression of "Church's Thesis". See in particular page 100 (The Undecidable) where he defines the...

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Halting problem
Minggu, 2026-05-03 15:11:28

run forever. Alan Turing proved in 1937 that the halting problem is undecidable, meaning that no general algorithm exists that can correctly solve the...

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On Formally Undecidable Propositions of Principia Mathematica and Related Systems
Selasa, 2023-10-17 00:17:16

Sätze der Principia Mathematica und verwandter Systeme I" ("On Formally Undecidable Propositions of Principia Mathematica and Related Systems I") is a paper...

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NP-hardness
Rabu, 2026-04-29 22:58:55

in NP. However, the opposite direction is not true: some problems are undecidable, and therefore even more difficult to solve than all problems in NP,...

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Conjecture
Sabtu, 2026-05-09 05:00:11

In mathematics, a conjecture is a proposition that is proffered on a tentative basis without proof. Some conjectures, such as the Riemann hypothesis or...

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Satisfiability modulo theories
Kamis, 2026-05-21 13:44:37

NP-complete, the SMT problem is typically NP-hard, and for many theories it is undecidable. Researchers study which theories or subsets of theories lead to a decidable...

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Decision problem
Kamis, 2026-02-12 07:12:30

accordingly. Some of the most important problems in mathematics are undecidable, e.g. the halting problem. The field of computational complexity theory...

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Robinson arithmetic
Kamis, 2026-03-19 15:20:05

axiomatized fragment of PA that is recursively incompletable and essentially undecidable. The background logic of Q is first-order logic with identity, denoted...

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Context-free grammar
Selasa, 2026-05-19 19:43:04

(do two given context-free grammars generate the same language?) is undecidable. Context-free grammars arise in linguistics where they are used to describe...

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Partially observable Markov decision process
Rabu, 2026-04-29 17:59:04

compressed as possible (to reduce overfitting). Planning in POMDP is undecidable in general. However, some settings have been identified to be decidable...

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List of statements independent of ZFC
Selasa, 2026-04-21 12:15:42

is consistent. A statement is independent of ZFC (sometimes phrased "undecidable in ZFC") if it can neither be proven nor disproven from the axioms of...

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Impossible object
Kamis, 2025-10-02 19:14:55

An impossible object (also known as an impossible figure or an undecidable figure) is a type of optical illusion that consists of a two-dimensional figure...

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Post correspondence problem
Senin, 2025-12-29 21:03:36

The Post correspondence problem is an undecidable decision problem that was introduced by Emil Post in 1946. Because it is simpler than the halting problem...

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Matrix mortality problem
Sabtu, 2025-09-13 01:20:33

The matrix mortality problem is known to be undecidable when n ≥ 3. In fact, it is already undecidable for sets of 6 matrices (or more) when n = 3, for...

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Peano axioms
Kamis, 2026-05-21 18:58:55

of Peano arithmetic or not. Hence, PA is an example of an undecidable theory. Undecidability arises already for the existential sentences of PA, due to...

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Theory of computation
Jumat, 2026-05-08 11:05:36

states that for all non-trivial properties of partial functions, it is undecidable whether a Turing machine computes a partial function with that property...

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Decidability of first-order theories of the real numbers
Jumat, 2024-04-26 06:15:46

is undecidable since this allows encoding of the undecidable theory of integers (see Richardson's theorem). Still, one can handle the undecidable case...

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Whitehead problem
Kamis, 2025-12-25 00:04:01

the existence of undecidable statements had been known since Gödel's incompleteness theorem of 1931, previous examples of undecidable statements (such...

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Mathematical logic
Rabu, 2026-05-20 01:16:56

dominant logic used by mathematicians. In 1931, Gödel published On Formally Undecidable Propositions of Principia Mathematica and Related Systems, which proved...

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Turing machine
Selasa, 2026-06-02 00:07:57

Computing Machine Davis, Martin, ed. (2004) [1965]. The Undecidable: Basic Papers on Undecidable Propositions, Unsolvable Problems and Computable Functions...

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Mathematical proof
Rabu, 2026-05-13 08:56:57

surprising being that almost all axiomatic systems can generate certain undecidable statements not provable within the system. The definition of a formal...

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Lists of problems
Jumat, 2026-06-05 23:16:06

problems in physics List of unsolved problems in mathematics List of undecidable problems List of NP-complete problems List of PSPACE-complete problems...

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Entscheidungsproblem
Senin, 2026-05-11 02:56:31

in all finite models. Trakhtenbrot's theorem shows that this is also undecidable. Some notations: S a t ( Φ ) {\displaystyle {\rm {{Sat}(\Phi )}}} means...

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Independence (mathematical logic)
Sabtu, 2026-02-28 15:15:00

prove from T that σ is false. Sometimes, σ is said (synonymously) to be undecidable from T. (This concept is unrelated to the idea of "decidability" as in...

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Semi-Thue system
Senin, 2026-06-08 04:53:22

finitely presented semigroups. Only in 1947 was the problem shown to be undecidable— this result was obtained independently by Emil Post and A. A. Markov...

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Reduction (complexity)
Kamis, 2025-12-11 01:38:14

Likewise, a reduction computing a noncomputable function can reduce an undecidable problem to a decidable one. As Michael Sipser points out in Introduction...

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Artificial intelligence
Senin, 2026-06-08 09:07:42

solved. Inference in both Horn clause logic and first-order logic is undecidable, and therefore intractable. However, backward reasoning with Horn clauses...

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Proof of impossibility
Rabu, 2026-04-22 23:55:34

proofs of impossibility found in the 20th century were those related to undecidability, which showed that there are problems that cannot be solved in general...

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Logical consequence
Rabu, 2025-12-17 18:27:38

Publications, Mineola, NY, 2003. Davis, Martin, ed. (1965), The Undecidable, Basic Papers on Undecidable Propositions, Unsolvable Problems And Computable Functions...

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Decidability
Minggu, 2022-11-06 22:04:25

mathematical logic Decidable problem and Undecidable problem Gödel's incompleteness theorem, a theorem on the undecidability of languages consisting of "true...

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Rice's theorem
Sabtu, 2026-05-09 20:59:12

theorem states that all non-trivial semantic properties of programs are undecidable. A semantic property is one about the program's behavior (for instance...

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Raphael M. Robinson
Kamis, 2025-11-27 18:05:18

proving a number of mathematical theories undecidable. In 1950 Robinson proved that an essentially undecidable theory need not have an infinite number of...

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Alan Turing
Minggu, 2026-06-07 21:06:47

problem by first showing that the halting problem for Turing machines is undecidable: it is not possible to decide algorithmically whether a Turing machine...

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First-order logic
Kamis, 2026-05-14 17:53:10

logical consequence of φ. Unlike propositional logic, first-order logic is undecidable (although semidecidable), provided that the language has at least one...

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Description number
Selasa, 2026-02-03 18:42:03

number. These numbers play a key role in Alan Turing's proof of the undecidability of the halting problem, and are very useful in reasoning about Turing...

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Word problem (mathematics)
Minggu, 2026-01-25 08:25:15

instances as well. Some deep results of computational theory concern the undecidability of this question in many important cases. In computer algebra one often...

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Higher-order logic
Rabu, 2026-04-22 03:39:46

intuitionistic type theory. Gérard Huet has shown that unifiability is undecidable in a type-theoretic flavor of third-order logic, that is, there can be...

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Higman's embedding theorem
Senin, 2025-06-02 09:30:51

algorithmically undecidable word problem. Indeed, it is fairly easy to construct a finitely generated recursively presented group with undecidable word problem...

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Ogden's lemma
Kamis, 2026-03-19 18:10:40

extended to show that deciding whether a CFG is inherently ambiguous is undecidable, by reduction to the Post correspondence problem. It can also show that...

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Computability theory
Minggu, 2026-03-08 07:24:46

are true or false. Many problems in mathematics have been shown to be undecidable after these initial examples were established. In 1947, Markov and Post...

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Universal Turing machine
Senin, 2026-05-11 20:38:18

general, undecidable in Turing's original paper. Rice's theorem shows that any non-trivial question about the output of a Turing machine is undecidable. A universal...

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Spectral gap (physics)
Minggu, 2025-10-05 05:57:59

shown that the problem of determining the existence of a spectral gap is undecidable in two or more dimensions. The authors used an aperiodic tiling of quantum...

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Unknowability
Jumat, 2025-10-24 22:15:24

sensible and must therefore remain unknowable. Modern inquiry encompasses undecidable problems and questions such as the halting problem, which in their very...

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Computable set
Jumat, 2025-08-08 00:06:11

natural number in a finite number of steps. A set is noncomputable (or undecidable) if it is not computable. A subset S {\displaystyle S} of the natural...

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Collatz conjecture
Selasa, 2026-06-02 21:07:31

that a natural generalization of the Collatz problem is algorithmically undecidable. Specifically, he considered functions of the form g ( n ) = a i n +...

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Group isomorphism problem
Senin, 2025-06-30 10:20:18

problems, formulated as ranging over all finitely presented groups, are undecidable. In the case of the isomorphism problem, this means that there does not...

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Automated theorem proving
Minggu, 2026-06-07 21:19:42

shortly after this positive result, Kurt Gödel published On Formally Undecidable Propositions of Principia Mathematica and Related Systems (1931), showing...

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Kurt Gödel
Senin, 2026-06-01 00:40:02

Principia Mathematica und verwandter Systeme (called in English "On Formally Undecidable Propositions of Principia Mathematica and Related Systems"). In that...

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Abelian group
Selasa, 2026-05-05 00:07:25

is also the first question in ordinary mathematics proved undecidable in ZFC; Undecidable even if ZFC is augmented by taking the generalized continuum...

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Emptiness problem
Senin, 2025-09-29 01:52:07

which is undecidable for certain alternating multi-head finite automata over single-letter alphabets. The emptiness problem is undecidable for context-sensitive...

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System F
Sabtu, 2026-05-09 02:45:08

However, type inference in System F (without explicit type annotations) is undecidable. Under the Curry–Howard isomorphism, System F corresponds to second-order...

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Mathematics
Minggu, 2026-05-24 02:27:14

2022-01-23. Retrieved 2022-01-23. Feferman, Solomon (1998). "Deciding the undecidable: Wrestling with Hilbert's problems" (PDF). In the Light of Logic. Logic...

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Leo Harrington
Selasa, 2025-10-21 21:23:26

the partially ordered set of computably enumerable Turing degrees is undecidable. Paris, J.; Harrington, L. (1977), "A Mathematical Incompleteness in...

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Syntax (programming languages)
Jumat, 2026-02-13 11:16:34

distinction between parsing and execution, and makes syntax analysis an undecidable problem in these languages, meaning that the parsing phase may not finish...

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Reiky de Valk
Minggu, 2026-06-07 04:42:29

Verleden Tijd Florian Short film De Overkammer Archie Short film 2022 #No_Filter Tyler 2025 Undecidable (posthumous release) Arturo Reyes Short film...

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Simplicial complex
Jumat, 2026-05-29 13:02:21

whether it is homeomorphic to a given geometric object. This problem is undecidable for any d-dimensional manifolds for d ≥ 5 {\displaystyle d\geq 5} . Abstract...

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Mortality (computability theory)
Senin, 2025-03-24 10:28:51

on it. Philip K. Hooper proved in 1966 that the mortality problem is undecidable. This is true both for a machine with a tape infinite in both directions...

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Rule of inference
Selasa, 2026-05-12 09:22:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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P versus NP problem
Minggu, 2026-05-24 05:52:43

to need more than exponential run time. Even more difficult are the undecidable problems, such as the halting problem. They cannot be completely solved...

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Alonzo Church
Jumat, 2026-05-08 05:23:55

truth of arbitrary propositions in a first-order mathematical theory, is undecidable. This is known as Church's theorem. His invention of the lambda calculus...

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Greibach's theorem
Minggu, 2025-04-13 23:25:32

theorem states that certain properties of formal language classes are undecidable. It is named after the computer scientist Sheila Greibach, who first...

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Mathematical problem
Kamis, 2025-09-11 04:52:14

quintic equation algebraically. Also provably unsolvable are so-called undecidable problems, such as the halting problem for Turing machines. Some well-known...

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Wang tile
Jumat, 2026-05-15 21:51:21

halt. The undecidability of the halting problem (the problem of testing whether a Turing machine eventually halts) then implies the undecidability of Wang's...

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Skolem arithmetic
Jumat, 2026-05-22 19:56:42

can express both multiplication and addition, the resulting theory is undecidable. If we have an ordering predicate on natural numbers (less than, < {\displaystyle...

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Turing's proof
Jumat, 2026-05-01 05:06:22

answered by computation; more technically, that some decision problems are "undecidable" in the sense that there is no single algorithm that infallibly gives...

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Termination analysis
Rabu, 2026-04-08 21:46:55

determine whether a given program halts for a given input and which is undecidable. The termination analysis is even more difficult than the halting problem:...

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Oracle machine
Rabu, 2026-02-18 19:10:46

{\displaystyle R} ⁠ can be of any complexity class, or it can even be an undecidable problem such as the halting problem. If another problem ⁠ R ′ {\displaystyle...

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MISRA C
Sabtu, 2026-06-06 20:48:04

required/advisory) Third edition: 2012 (directives; rules, Decidable/Undecidable) MISRA compliance: 2016, updated 2020 MISRA C:2023 (MISRA C Third edition...

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Reductionism
Jumat, 2026-04-10 05:40:52

propositions are known as formally undecidable propositions. For example, the continuum hypothesis is undecidable in the Zermelo–Fraenkel set theory as...

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Indicator function
Kamis, 2025-09-11 09:42:17

Kurt Gödel described the representing function in his 1934 paper "On undecidable propositions of formal mathematical systems" (the symbol "¬" indicates...

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Emil Leon Post
Rabu, 2026-05-27 17:35:54

undecidability. He showed that the Post correspondence problem (PCP) of satisfying their constraints is, in general, undecidable. The undecidability of...

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Feferman–Vaught theorem
Selasa, 2026-05-05 10:38:18

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Andrey Markov Jr.
Jumat, 2026-01-02 16:57:48

results showing that the classification of four-dimensional manifolds is undecidable: no general algorithm exists for distinguishing two arbitrary manifolds...

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Static program analysis
Senin, 2026-03-23 16:47:50

of violation of a specification on the final result of a program) is undecidable: there is no mechanical method that can always answer truthfully whether...

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Church–Turing thesis
Senin, 2026-04-13 15:44:39

Publishers. pp. 137–160. Davis, Martin, ed. (1965). The Undecidable, Basic Papers on Undecidable Propositions, Unsolvable Problems And Computable Functions...

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Alfred Tarski
Jumat, 2026-06-05 01:37:57

arithmetic is also incomplete by Gödel's incompleteness theorem. In his 1953 Undecidable theories, Tarski et al. showed that many mathematical systems, including...

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Scott–Curry theorem
Sabtu, 2025-04-12 09:54:15

semantic properties of programs are undecidable. The theorem has the immediate consequence that it is an undecidable problem to determine if two lambda...

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Correctness (computer science)
Minggu, 2026-05-24 20:25:05

(termination proof) can never be fully automated, since the halting problem is undecidable. For example, successively searching through the positive integers (1...

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Metamathematics
Minggu, 2026-03-22 22:16:29

Metamathematics is the study of mathematics itself using mathematical methods. This study produces metatheories, which are mathematical theories about...

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Type system
Senin, 2026-04-27 04:45:27

comes at a price when the type inferences (and other properties) become undecidable, and when more attention must be paid by the programmer to annotate code...

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Optimizing compiler
Rabu, 2026-02-18 23:28:15

analysis indicates that some optimization problems are NP-complete, or even undecidable. Also, producing perfectly optimal code is not possible since optimizing...

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Quantum algorithm
Kamis, 2026-05-21 19:56:34

superposition or quantum entanglement. Problems that are undecidable using classical computers remain undecidable using quantum computers. What makes quantum algorithms...

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Three-valued logic
Sabtu, 2026-01-17 00:52:34

Stephen Cole Kleene used a third value to represent predicates that are "undecidable by [any] algorithms whether true or false" As with bivalent logic, truth...

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Mathematical universe hypothesis
Rabu, 2026-05-20 01:03:35

time itself may not be predictable by a halting program, due to the undecidability of the halting problem. In response, Tegmark notes that a constructive...

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Intuitionism
Selasa, 2026-05-05 01:56:18

Intuitionism (with respect to Brouwer). Martin Davis (ed.) (1965), The Undecidable, Raven Press, Hewlett, NY. Compilation of original papers by Gödel, Church...

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Post–Turing machine
Jumat, 2026-03-27 02:05:41

always order a printing and a motion, right, left, or none" (footnote 12, Undecidable, p. 300) Like Turing, he defined erasure as printing a symbol "S0". And...

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Weak interpretability
Kamis, 2026-01-22 21:31:45

Giorgi Japaridze in 1992. Interpretability logic Tarski, Alfred (1953), Undecidable theories, Studies in Logic and the Foundations of Mathematics, Amsterdam:...

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Formal verification
Selasa, 2025-04-15 17:45:11

algorithmic implementations are guaranteed to terminate with an answer, or undecidable, meaning that they may never terminate. By bounding the scope of possibilities...

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Axiom
Sabtu, 2026-05-23 13:04:29

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Expressive power (computer science)
Senin, 2026-02-09 02:59:48

formalism say. Decision problems become harder to answer or completely undecidable. Formal language theory mostly studies formalisms to describe sets of...

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Justification (epistemology)
Selasa, 2025-12-30 10:14:41

instead of justifying them. Skepticism – Knowledge is impossible or undecidable. Robert Fogelin claims to detect a suspicious resemblance between the...

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Yang–Mills existence and mass gap
Minggu, 2026-05-31 07:13:04

mass gap (a special case of a spectral gap) in a system is known to be undecidable, meaning no computer algorithm exists that can find the answer programmatically...

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Paul Cohen
Sabtu, 2026-03-14 11:54:19

disproved from these axioms. In this sense, the continuum hypothesis is undecidable, and it is the most widely known example of a natural statement that...

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Adian–Rabin theorem
Kamis, 2025-07-24 03:14:54

"reasonable" properties of finitely presentable groups are algorithmically undecidable. The theorem is due to Sergei Adyan (1955) and, independently, Michael...

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Interpretability
Minggu, 2025-08-03 12:45:09

Handbook of Proof Theory. North-Holland: 476–546. Alfred Tarski, Andrzej Mostowski, and Raphael Robinson (1953) Undecidable Theories. North-Holland. v t e...

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Risch algorithm
Kamis, 2026-04-23 07:17:17

Specifically, the algorithm cannot solve the constant problem, which is undecidable when it needs to determine whether an arbitrary complex number expression...

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Pharmakon
Selasa, 2025-11-25 03:24:59

"poison"] actually do interpretive violence to what would otherwise remain undecidable." Whereas a straightforward view on Plato's treatment of writing (in...

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Combinatory logic
Kamis, 2026-05-14 23:45:36

if any, are not applied to enough arguments to be simplified. It is undecidable whether a general combinatory term has a normal form; whether two combinatory...

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Back-and-forth method
Selasa, 2025-10-14 02:41:14

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Tuple-generating dependency
Selasa, 2025-11-18 21:35:04

TGDs (or more generally EDs) and, if it terminates (which is a priori undecidable), outputs an instance that does satisfy the TGDs. A tuple-generating...

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Programming language
Sabtu, 2026-05-23 00:36:29

programmer to alter the behavior of the parser make syntax analysis an undecidable problem, and generally blur the distinction between parsing and execution...

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Institutional model theory
Jumat, 2025-10-17 16:10:21

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Polymorphic recursion
Jumat, 2025-10-17 16:23:40

polymorphic recursion is equivalent to semi-unification and therefore undecidable and requires the use of a semi-algorithm or programmer-supplied type...

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John Horton Conway
Senin, 2026-06-08 03:25:48

that a natural generalization of the Collatz problem is algorithmically undecidable. Related to that, he developed the esoteric programming language FRACTRAN...

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Richardson's theorem
Minggu, 2025-11-09 01:03:01

In mathematics, Richardson's theorem establishes the undecidability of the equality of real numbers defined by expressions involving integers, π, ln 2...

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Hypercomputation
Jumat, 2025-12-19 00:30:30

used this device to prove that even in those more powerful systems, undecidability is still present. Turing's oracle machines are mathematical abstractions...

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Existential quantification
Selasa, 2026-04-07 07:13:54

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Conway's Game of Life
Selasa, 2026-06-02 01:36:03

may therefore execute arbitrary programs. By the halting problem it is undecidable whether an arbitrary program executed in the Game of Life would ever...

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Outline of logic
Minggu, 2026-02-01 10:03:39

problem History of the Church–Turing thesis Lambda calculus List of undecidable problems Post correspondence problem Post's theorem Primitive recursive...

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Impossible trident
Selasa, 2025-11-11 14:35:49

Roger Hayward's Undecidable Monument...

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Model-theoretic grammar
Minggu, 2025-12-21 19:09:49

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Epsilon-induction
Minggu, 2026-03-22 01:03:17

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Robinson's joint consistency theorem
Rabu, 2026-06-03 12:00:46

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Register machine
Kamis, 2026-05-28 01:40:31

included in The Undecidable. The mathematics of Church, Rosser, and Kleene that appear as reprints of original papers in The Undecidable is carried further...

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Computability
Rabu, 2026-04-29 01:07:35

called non-computable or undecidable. An extension of the halting problem is called Rice's theorem, which states that it is undecidable (in general) whether...

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List of mathematics books
Sabtu, 2026-03-14 23:59:25

Lakatos The Principles of Mathematics — Bertrand Russell On Formally Undecidable Propositions of Principia Mathematica and Related Systems — Kurt Gödel...

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Satisfiability
Sabtu, 2026-02-21 22:09:25

satisfiability is undecidable. More specifically, it is a co-RE-complete problem and therefore not semidecidable. This fact has to do with the undecidability of the...

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Metric interval temporal logic
Selasa, 2025-10-28 15:37:03

This fragment is often preferred to MTL because some problems that are undecidable for MTL become decidable for MITL. A MITL formula is an MTL formula,...

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THOG problem
Minggu, 2026-05-03 16:35:19

THOG. For each of the other symbols, are they a) definitely a THOG, b) undecidable, or c) definitely not a THOG?" Presented in this form, the task is quite...

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Strange loop
Senin, 2026-04-13 10:56:25

Hilbert-Bernays provability conditions do not obtain), one can construct formally undecidable (or even formally refutable) Henkin-sentences for the arithmetical system...

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Predicate (logic)
Minggu, 2026-04-12 18:30:13

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Program analysis
Minggu, 2025-09-21 21:32:34

vulnerability. Due to many forms of static analysis being computationally undecidable, the mechanisms for performing it may not always terminate with the correct...

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Power set
Senin, 2026-05-25 22:22:42

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Linear grammar
Selasa, 2025-02-18 23:55:33

cannot be accepted in linear time in the general case. Furthermore, it is undecidable whether a given context-free language is a linear context-free language...

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Robert Berger (mathematician)
Senin, 2025-11-03 14:32:18

another result proved by Berger: that the so-called domino problem is undecidable, disproving a conjecture of Hao Wang, Berger's advisor. The result is...

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Conjunctive query
Senin, 2025-12-01 09:48:58

conjunctive query) is known as the Datalog boundedness problem and is undecidable. Extensions of conjunctive queries capturing more expressive power include:...

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Specters of Marx
Sabtu, 2025-07-19 01:19:21

United States - Japan - Europe. Contradictions of the free market. The undecidable conflicts between protectionism and free trade. The unstoppable flow...

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Rewriting
Minggu, 2026-05-24 16:43:12

consisting of one rule with a linear left-hand side is undecidable. Termination is also undecidable for systems using only unary function symbols; however...

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Jean Baudrillard
Sabtu, 2026-05-16 21:39:58

Banal Reality: Comparative Thoughts on Simulation and Concreteness". The Undecidable Unconscious: A Journal of Deconstruction and Psychoanalysis. 6 (1): 29–45...

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Bootstrapping (compilers)
Kamis, 2025-11-20 17:14:29

science, such as the variation of the proof that the halting problem is undecidable that uses Rice's Theorem. Due to security concerns regarding the Trusting...

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Timeline of mathematical logic
Minggu, 2025-10-26 23:08:44

problem is undecidable. 1955 - Evertt William Beth develops semantic tableaux. 1958 - William Boone independently proves the undecidability of the uniform...

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Monadic second-order logic
Minggu, 2026-05-03 06:35:57

that case. The satisfiability problem for monadic second-order logic is undecidable in general because this logic subsumes first-order logic. The monadic...

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Law of noncontradiction
Minggu, 2026-04-05 08:38:01

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Word problem for groups
Sabtu, 2026-05-30 07:41:33

The word problems for certain groups provide well-known examples of undecidable problems. If A {\displaystyle A} is a finite set of generators for G...

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Simply typed lambda calculus
Jumat, 2026-05-01 09:36:27

{\displaystyle \beta \eta } -equivalence is undecidable. Huet showed in 1973 that 3rd order unification is undecidable and this was improved upon by Baxter in...

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Complementation of automata
Minggu, 2025-11-16 04:48:29

complementation (i.e., builds the complement automaton), or can the task be undecidable? Again, the answer to this question depends on the automaton class used...

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Trakhtenbrot's theorem
Sabtu, 2025-11-08 15:07:37

of validity in first-order logic on the class of all finite models is undecidable. In fact, the class of valid sentences over finite models is not recursively...

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Logical connective
Minggu, 2026-05-24 07:51:25

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Conjunctive grammar
Selasa, 2026-01-20 08:54:54

multiplication. A property that is undecidable already for context-free languages or finite intersections of them, must be undecidable also for conjunctive grammars;...

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Variable (mathematics)
Minggu, 2026-05-24 19:10:14

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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History of group theory
Selasa, 2026-01-20 15:14:51

theories within the study of groups to be undecidable. Earlier, Alfred Tarski proved elementary group theory undecidable. The period of 1960-1980 was one of...

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Hybrid system
Senin, 2025-12-01 12:51:59

abstraction refinement, and barrier certificates. Most verification tasks are undecidable, making general verification algorithms impossible. Instead, the tools...

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Liskov substitution principle
Selasa, 2026-05-26 18:46:29

parameter types and covariance of the return type. Behavioural subtyping is undecidable in general: if q is the property "method for x always terminates", then...

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Theory of everything
Sabtu, 2026-05-30 22:00:09

limit-computable, deterministic universes whose pseudo-randomness based on undecidable, Gödel-like halting problems is extremely hard to detect but does not...

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LALR parser
Jumat, 2026-02-20 02:59:51

grammars that are not LL(k) grammars and vice versa. In fact, it is undecidable whether a given LL(1) grammar is LALR(k) for any k > 0 {\displaystyle...

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Garden of Eden (cellular automaton)
Selasa, 2026-05-26 16:38:24

found by an efficient algorithm, but for higher dimensions this is an undecidable problem. Nevertheless, computer searches have succeeded in finding these...

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Computably enumerable set
Senin, 2026-05-18 03:21:31

this poset is a lattice. The theory of this lattice is known to be an undecidable problem. Similarly, the set of all computably enumerable vector spaces...

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Model theory
Selasa, 2026-05-12 10:07:48

{M}}} interprets another whose theory is undecidable, then M {\displaystyle {\mathcal {M}}} itself is undecidable. For a sequence of elements a 1 , … , a...

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John von Neumann
Kamis, 2026-06-04 07:31:51

Neumann suggested to Gödel that he should try to transform his results for undecidable propositions about integers. Less than a month later, von Neumann communicated...

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Constructive analysis
Kamis, 2026-02-26 17:30:12

In mathematics, constructive analysis is mathematical analysis done according to some principles of constructive mathematics. The name of the subject contrasts...

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Complement (set theory)
Jumat, 2026-05-22 22:28:50

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Expression (mathematics)
Minggu, 2026-05-24 10:49:07

programming language theory. The equivalence of two lambda expressions is undecidable (but see unification (computer science)). This is also the case for the...

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Yury Yershov
Selasa, 2024-10-29 23:04:01

University. In 1964 he successfully defended his PhD thesis "Decidable and Undecidable Theories" (advisor Anatoly Maltsev). In 1966 he successfully defended...

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Reverse mathematics
Jumat, 2026-05-15 16:02:08

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Formal grammar
Sabtu, 2026-02-14 08:07:53

CRC Press, p. 233, ISBN 9781466513457. For more on this subject, see undecidable problem. Chomsky, Noam (Sep 1956). "Three models for the description...

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Hierarchy of the sciences
Minggu, 2026-02-22 04:37:08

"Scientism and Scientific Knowledge of Things and God", Mathematical Undecidability, Quantum Nonlocality and the Question of the Existence of God, Dordrecht:...

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Recursion
Rabu, 2026-05-20 01:08:43

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Object-oriented programming
Selasa, 2026-05-26 09:17:40

to handle using OOP's concept of inheritance. Behavioral subtyping is undecidable in general, so it cannot be easily implemented by a compiler. Because...

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Agent verification
Rabu, 2026-06-03 01:02:43

number of agents can join the system at runtime, the problem is generally undecidable, though solutions are available for specific cases. Even more so in the...

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Theorem
Minggu, 2026-05-17 21:29:18

arithmetic Tarski's undefinability theorem Church-Turing theorem of undecidability Löb's theorem Löwenheim–Skolem theorem Lindström's theorem Craig's theorem...

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Principia Mathematica
Senin, 2026-05-25 13:15:42

p. 130. Kleene 1952, p. 46. Gödel, Kurt (2022) [1962]. On Formally Undecidable Propositions of Principia Mathematica and Related Systems. Translated...

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Hindley–Milner type system
Minggu, 2026-03-22 09:41:29

type inference algorithms, which often came out to be NP-hard, if not undecidable with respect to termination. Thus the HM performs as well as the best...

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Logic of graphs
Selasa, 2026-04-21 01:04:24

for graphs that are not constrained to be finite remains undecidable. It is also undecidable to distinguish between the first-order sentences that are...

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Recursively enumerable language
Selasa, 2026-04-14 00:25:16

hence it is recursively enumerable. On the other hand, the problem is undecidable. Some other recursively enumerable languages that are not recursive include:...

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T-schema
Rabu, 2025-01-01 00:22:36

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Language-Theoretic Security
Sabtu, 2026-02-28 10:42:37

have been followed. In the general case, spatial memory correctness is undecidable. If any proof of spatial memory correctness is to be made, it is therefore...

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Constructor theory
Minggu, 2026-03-22 21:32:19

special case of superinformation. Calculating Space Computability theory Undecidable problem Quantum circuit Generalized probabilistic theory Heaven, Douglas...

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Richard's paradox
Senin, 2024-11-18 16:55:19

syntactical incompleteness result in the introductory section of "On Formally Undecidable Propositions in Principia Mathematica and Related Systems I". The paradox...

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Penrose tiling
Minggu, 2026-06-07 05:59:17

colors on adjacent domino edges. He observed that if this problem were undecidable, then there would have to exist an aperiodic set of Wang dominoes. At...

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Praiseworthy (novel)
Kamis, 2026-01-29 14:03:57

eye that causes the story to hover between tragedy and farce. This undecidability is the symptom of the scale of the novel's address. Wright is that rare...

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Metric temporal logic
Jumat, 2025-12-05 17:09:47

formalism for real-time systems. Full MTL over infinite timed words is undecidable. The full metric temporal logic is defined similarly to linear temporal...

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Garbage (computer science)
Rabu, 2025-07-09 05:58:42

accessed; determining the latter requires code analysis, and is in general undecidable. Syntactic garbage is a (usually strict) subset of semantic garbage,...

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Martin Davis (mathematician)
Kamis, 2026-02-19 22:36:05

2000. ISBN 9780393322293. Davis, Martin (2004). The Undecidable : Basic papers on undecidable propositions, unsolvable problems and computable functions...

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Boolean algebra
Rabu, 2026-04-15 15:54:59

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Bijection
Senin, 2026-06-01 19:36:40

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Hilbert's tenth problem
Kamis, 2026-05-28 20:12:08

answering that question. In modern terms, Hilbert's tenth problem is an undecidable problem. In a Diophantine equation, there are two kinds of variables:...

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Context-sensitive grammar
Kamis, 2026-02-19 21:36:31

context-sensitive grammars (given a context-sensitive grammar G, is L(G)=∅ ?) is undecidable. Savitch has proven the following theoretical result, on which he bases...

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General recursive function
Selasa, 2026-03-03 00:51:19

difference is, that it becomes undecidable whether a specific function definition defines a μ-recursive function, as it is undecidable whether a computable (i...

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List of impossible puzzles
Senin, 2025-03-03 07:31:50

Product Puzzle", which is not impossible -gry, a word puzzle List of undecidable problems, no algorithm can exist to answer a yes–no question about the...

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Subset
Selasa, 2026-05-26 13:24:00

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Aporia
Selasa, 2025-12-09 04:08:02

refers to three "aporias": "the epoche of the rule", "the ghost of the undecidable", and "the urgency that obstructs the horizon of knowledge". Aporia is...

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Formation rule
Jumat, 2025-05-02 14:01:11

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Complexity class
Rabu, 2026-05-20 22:22:51

{\textsf {P}}\subsetneq {\textsf {P/poly}}} (for example, there are some undecidable problems that are in P/poly). P/poly has a number of properties that...

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Tessellation
Sabtu, 2026-05-16 20:20:47

the halting problem is undecidable, the problem of deciding whether a Wang domino set can tile the plane is also undecidable. Truchet tiles are square...

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Van Wijngaarden grammar
Minggu, 2025-09-07 04:51:46

generates a given string whether a W-grammar generates no strings at all are undecidable. Curtailed variants, known as affix grammars, were developed, and applied...

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T2 Temporal Prover
Selasa, 2026-02-24 05:43:16

the halting problem for particular cases, since the general problem is undecidable. It provides a solution which is sound, meaning that when it states that...

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Abstraction (computer science)
Selasa, 2025-12-09 01:39:49

from them—even though the abstraction may simply yield a result of undecidability. For instance, students in a class may be abstracted by their minimal...

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Lemma (mathematics)
Senin, 2026-05-18 13:05:21

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Tibetans in India
Rabu, 2026-02-25 07:18:12

Oha, Obododimma (2008-01-01), "Language, Exile and the Burden of Undecidable Citizenship: Tenzin Tsundue and the Tibetan Experience", Exile Cultures...

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Francisco Dória
Kamis, 2026-06-04 05:47:30

logician and philosopher Newton da Costa) is the proof that chaos theory is undecidable (published in 1991), and when properly axiomatized within classical set...

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Antichrist (film)
Minggu, 2026-06-07 11:34:42

"in-between bits, the judders and rumbles and low howls drifting somewhere undecidable between composed music and sound design ... the un-music, the audiable...

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Real number
Jumat, 2026-06-05 19:32:55

be computable. Moreover, the equality of two computable numbers is an undecidable problem. Some constructivists accept the existence of only those reals...

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Free module
Selasa, 2026-04-21 12:43:38

non-commutative) local ring is free. Sometimes, whether a module is free or not is undecidable in the set-theoretic sense. A famous example is the Whitehead problem...

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Sappho
Rabu, 2026-06-03 15:16:42

poetry can be read as queer even if the question of her lesbianism is undecidable. In antiquity, Sappho's poetry was highly admired, and several ancient...

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Codomain
Sabtu, 2026-05-02 06:06:50

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Intersection type discipline
Minggu, 2026-04-19 07:27:58

higher intersection types, typability becomes undecidable, in general. Complementarily, undecidability of the dual problem of type inhabitation in prominent...

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Alasdair Urquhart
Senin, 2026-06-01 23:29:11

non-classical logic. Amongst his most notable accomplishments is the proof of undecidability of the relevance logic R. He published numerous scientific papers in...

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List of superseded scientific theories
Minggu, 2026-05-03 07:54:19

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Thoralf Skolem
Selasa, 2026-04-28 04:41:55

addition and multiplication) is incompletable and hence a posteriori undecidable. Hao Wang praised Skolem's work as follows: Skolem tends to treat general...

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Eudaimonia
Sabtu, 2026-06-06 14:36:09

(unstable, unbalanced, not measurable), and anepikrita (unjudged, unfixed, undecidable). Therefore, neither our sense-perceptions nor our doxai (views, theories...

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Cellular automaton
Minggu, 2026-05-31 05:43:16

which are sometimes called Culik–Yu classes; membership in these proved undecidable. Wolfram's class 2 can be partitioned into two subgroups of stable (fixed-point)...

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Rank of a group
Sabtu, 2025-11-22 17:58:05

about it. Known results include: The rank problem is algorithmically undecidable for the class of all finitely presented groups. Indeed, by a classical...

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Perl
Selasa, 2026-06-02 18:59:51

2008. and "Perl is Undecidable". The Perl Review. 5: 7–11. Fall 2008., available online at Kegler, Jeffrey. "Perl and Undecidability". Archived from the...

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Datalog
Sabtu, 2026-05-16 05:14:53

queries. Solving the boundedness problem on arbitrary Datalog programs is undecidable, but it can be made decidable by restricting to some fragments of Datalog...

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Atomic sentence
Rabu, 2025-08-06 02:17:20

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Signature (logic)
Jumat, 2025-10-31 07:34:54

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Substance theory
Selasa, 2026-02-24 03:31:18

(unstable, unbalanced, not measurable), and anepikrita (unjudged, unfixed, undecidable). Therefore, neither our sense-perceptions nor our doxai (views, theories...

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Structural induction
Minggu, 2023-12-03 18:32:17

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Binary operation
Selasa, 2026-06-02 04:51:11

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Bjorn Poonen
Selasa, 2026-03-03 23:42:17

elected in 2012 Chauvenet Prize: the 2011 winner, for his article "Undecidability in number theory" Miller Research Professorship – University of California...

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Boolean circuit
Sabtu, 2025-11-01 12:11:16

proper (i.e. P ⊊ {\displaystyle \subsetneq } P/poly) because there are undecidable problems that are in P/poly. P/poly turns out to have a number of properties...

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Jacques Derrida
Rabu, 2026-06-03 08:32:32

of Authority’”, Derrida emphasizes the relation between decision and undecidability, and the tension between normativity and singularity. This interpretation...

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Finite model theory
Selasa, 2026-04-28 23:41:36

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Simplicial complex recognition problem
Sabtu, 2025-06-21 11:59:17

is homeomorphic to another fixed simplicial complex. The problem is undecidable for complexes of dimension 5 or more. An abstract simplicial complex...

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Alain Badiou
Selasa, 2026-06-02 23:30:33

indiscernible, this generic point; and thus nominate, and give name to, the undecidable event. Badiou thereby marks out a philosophy by which to refute the apparent...

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Propositional variable
Minggu, 2026-02-08 20:25:00

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Chatterton (novel)
Kamis, 2026-05-21 05:45:09

attempt: "his authority as a story-teller to decide the historically undecidable mystery of Chatterton's death" Thus, "Chatterton is not a novel on the...

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Pyrrhonism
Kamis, 2026-01-29 21:19:02

of proofs. According to the mode deriving from dispute, we find that undecidable dissension about the matter proposed has come about both in ordinary...

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Consistency
Kamis, 2026-05-28 05:36:47

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Formal language
Rabu, 2026-06-03 11:50:57

Emil Post later termed 'Thue Systems', and gave an early example of an undecidable problem. Post would later use this paper as the basis for a 1947 proof...

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Culture of Thailand
Sabtu, 2026-05-30 19:41:49

Old Series. 4 (3): 12. Padamalangula, Namphueng (2003). The play of undecidability: A deconstructive analysis of "Traiphum Phra Ruang"("Three Worlds According...

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Naimark's problem
Kamis, 2024-01-25 13:41:10

{\displaystyle {\mathsf {ZFC}}} remains unknown. List of statements undecidable in Z F C {\displaystyle {\mathsf {ZFC}}} Gelfand–Naimark theorem Akemann...

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Multiverse
Jumat, 2026-06-05 20:41:20

time itself may not be predictable by a halting program, due to the undecidability of the halting problem. He also explicitly discusses the more restricted...

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Flamen
Kamis, 2026-05-28 04:54:05

Emperors (divus). The etymology of flamen remains obscure, and perhaps undecidable. The term is traditionally connected with the Proto-Germanic verb *blōtaną...

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Nassim Nicholas Taleb
Sabtu, 2026-06-06 21:48:46

the mathematician Raphael Douady, he called the problem statistical undecidability (Douady and Taleb, 2010). Taleb has described his main challenge as...

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Non-well-founded set theory
Kamis, 2026-01-29 10:51:22

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Parsing expression grammar
Kamis, 2026-05-07 08:16:50

expression language from its grammar. Furthermore, it is algorithmically undecidable whether the language recognized by a parsing expression grammar is empty...

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Deconstruction
Selasa, 2026-05-26 05:37:47

a free play but from the necessity of analysis. Derrida called these undecidables—that is, unities of simulacrum—"false" verbal properties (nominal or...

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Ross–Littlewood paradox
Senin, 2025-07-21 19:51:54

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Cristopher Moore
Selasa, 2026-02-03 13:18:32

structure of the network. Other topics in Moore's research include modeling undecidable problems by physical systems, phase transitions in random instances of...

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Saturated set
Jumat, 2026-01-30 21:22:49

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Quantum computing
Minggu, 2026-06-07 23:36:39

terms of computability. This means that quantum computers cannot solve undecidable problems like the halting problem, and the existence of quantum computers...

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Law of excluded middle
Sabtu, 2026-04-25 00:36:24

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Pale Fire
Jumat, 2026-05-01 13:15:47

are newcomers to the book. Some readers see the book as oscillating undecidably between these alternatives, like the Rubin vase (a drawing that may be...

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Computable number
Minggu, 2026-05-17 20:30:32

number that encodes the solution of the halting problem (or any other undecidable problem) according to a chosen encoding scheme. Chaitin's constant, Ω...

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Decider (Turing machine)
Jumat, 2026-02-06 22:49:43

arbitrary Turing machine, determining whether it is a decider is an undecidable problem. This is a variant of the halting problem, which asks for whether...

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Brouwer–Hilbert controversy
Minggu, 2026-04-05 20:27:04

ISBN 0-7923-6151-2, pages 221–230. Martin Davis, 1965. The Undecidable: Basic Papers on Undecidable Propositions, Unsolvable Problems, and Computable Functions...

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Zygmunt Bauman
Senin, 2026-06-01 10:49:42

the stranger as the person who is present yet unfamiliar, society's undecidable. In Modernity and Ambivalence Bauman attempted to give an account of...

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Pyrrho
Senin, 2026-06-01 16:46:03

Classical Quarterly, 52 (2002): 248–56. Svavarsson, Svavar Hrafn, "Pyrrho's undecidable nature", Oxford Studies in Ancient Philosophy, 27 (2004): 249–295. Library...

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Foundations of mathematics
Senin, 2026-04-13 21:59:54

provided us with the right preconceptions. Weinberg believed that any undecidability in mathematics, such as the continuum hypothesis, could be potentially...

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Second-order cybernetics
Selasa, 2026-06-02 16:21:57

doi:10.1007/978-4-431-55639-8 Scholte, T. (2019). "Heuristics for the Undecidable." She Ji: The Journal of Design, Economics, and Innovation, 5(4), 379–382...

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Condensation lemma
Sabtu, 2025-12-27 06:29:17

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Web Ontology Language
Minggu, 2026-05-24 02:57:34

the meaning of the pre-defined (RDF or OWL) vocabulary. OWL Full is undecidable, so no reasoning software is able to perform complete reasoning for it...

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Self-hosting (compilers)
Jumat, 2026-01-16 14:15:29

theoretical computer science, such as the proof that the halting problem is undecidable. Ken Thompson started development on Unix in 1968 by writing and compiling...

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Truth-value semantics
Kamis, 2024-07-11 19:08:34

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Evert Willem Beth
Senin, 2026-06-01 02:56:17

only semi-effective for first-order logic, since first-order logic is undecidable, as showed by Church's theorem. This method is considered by many to...

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Domain of a function
Minggu, 2026-05-10 12:21:01

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Proof by infinite descent
Jumat, 2026-06-05 01:28:27

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Surjective function
Rabu, 2026-04-01 00:48:57

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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DatalogZ
Rabu, 2025-10-29 16:08:26

atom (fact) is entailed by a DatalogZ program is RE-complete (hence, undecidable), which can be shown by a reduction to diophantine equations. The syntax...

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Mihalis Yannakakis
Minggu, 2026-03-08 06:01:54

Sequence Charts (MSC), where it was shown that weak realizability is undecidable for bounded MSC-graphs and that safe-realizability is in EXPSPACE, along...

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Function (computer programming)
Senin, 2026-06-08 07:00:35

Determining whether a callable has a side effect is difficult – indeed, undecidable by virtue of Rice's theorem. So, while this optimization is safe in a...

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Take-grant protection model
Rabu, 2025-02-19 08:21:43

rules. It shows that even though the question of safety is in general undecidable, for specific systems it is decidable in linear time. The model represents...

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Tarski's high school algebra problem
Minggu, 2026-01-11 06:09:14

expressible in closed-form from elementary functions Richardson's theorem – Undecidability of equality of real numbers Stanley Burris, Simon Lee, Tarski's high...

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Contraposition
Jumat, 2025-11-28 05:40:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Equivalence relation
Rabu, 2026-02-11 05:41:20

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Verena Huber-Dyson
Kamis, 2026-04-30 04:54:55

did research on the interface between algebra and logic, focusing on undecidability in group theory. At the time of her death, she was emeritus faculty...

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Negation
Jumat, 2026-01-16 10:57:13

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Process calculus
Kamis, 2026-05-07 13:52:58

unwieldy characterisations of equality (which in most cases must also be undecidable, as a consequence of the halting problem). Bisimulations are a technical...

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List of computability and complexity topics
Rabu, 2026-04-29 22:16:57

Halting problem Correctness Post correspondence problem Decidable language Undecidable language Word problem for groups Wang tile Penrose tiling Computable...

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Typed lambda calculus
Rabu, 2025-10-22 21:55:22

ISSN 0956-7968. since the halting problem for the latter class was proven to be undecidable "What to know before debating type systems | Ovid [blogs.perl.org]"....

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Conjunction/disjunction duality
Rabu, 2025-04-16 21:47:02

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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William Boone (mathematician)
Senin, 2026-03-09 02:54:24

exists a finitely presented group G such that the word problem for G is undecidable. A different proof was obtained by Boone in a paper published in 1958...

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Classical logic
Sabtu, 2026-05-16 11:36:02

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Russell's paradox
Minggu, 2026-06-07 00:18:13

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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EXPTIME
Senin, 2025-08-25 22:00:42

the time hierarchy theorem. In computability theory, one of the basic undecidable problems is the halting problem: deciding whether a deterministic Turing...

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Injective function
Rabu, 2026-04-01 00:47:42

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Channel system (computer science)
Jumat, 2025-10-03 07:45:07

w_{m})\in R(S)} . Most problem related to perfect channel system are undecidable. This is due to the fact that such a machine may simulates the run of...

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Turing machine examples
Kamis, 2025-10-16 14:49:15

Company. ISBN 0-7167-2064-7. Davis, Martin (1965). The Undecidable: Basic Papers on Undecidable Propositions, Unsolvable Problems and Computable Functions...

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Recursive language
Senin, 2025-07-14 15:12:28

Turing machine running an algorithm that terminates on all inputs. An undecidable problem is a problem that is not decidable. As noted above, every context-sensitive...

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Limit (mathematics)
Senin, 2026-06-01 00:40:45

modulus of convergence is undecidable. In recursion theory, the limit lemma proves that it is possible to encode undecidable problems using limits. There...

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Saul Kripke
Rabu, 2026-05-13 20:14:54

combined logic S4.1 (in fact, even K4.1) is canonical. In general, it is undecidable whether a given axiom is canonical. We know a nice sufficient condition:...

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Empty set
Kamis, 2026-04-23 11:58:52

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Sahlqvist formula
Kamis, 2026-05-07 18:16:39

decidable set of modal formulas with first-order correspondents. Since it is undecidable, by Chagrova's theorem, whether an arbitrary modal formula has a first-order...

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Melencolia I
Sabtu, 2026-05-16 11:10:55

Bałus, Wojciech (1994). "Dürer's 'Melencolia I': Melancholy and the Undecidable". Artibus et Historiae. 15 (30): 9–21. doi:10.2307/1483470. JSTOR 1483470...

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Mathematical object
Kamis, 2026-06-04 03:48:51

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Crocodile dilemma
Kamis, 2025-10-09 03:07:32

of paradoxes Self-reference Halting problem – the usual proof of its undecidability uses a similar contradiction Barile, Margherita. "Crocodile's Dilemma...

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Ambiguous grammar
Jumat, 2025-12-12 08:20:04

The decision problem of whether an arbitrary grammar is ambiguous is undecidable because it can be shown that it is equivalent to the Post correspondence...

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Julia Robinson
Sabtu, 2026-05-16 02:35:58

Her dissertation showed that the theory of the rational numbers was an undecidable problem, by demonstrating that elementary number theory could be defined...

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Combinatorics on words
Minggu, 2026-03-08 10:44:55

that this problem is undecidable; consequently, any word problem that has a reduction from this basic problem is likewise undecidable. Combinatorics on words...

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Cardinal number
Rabu, 2026-04-22 00:25:09

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Diaconescu's theorem
Sabtu, 2026-05-16 01:51:34

natural numbers form a set one may quantify over), then set-bounded but undecidable propositions can be expressed. In constructive type theory, or in Heyting...

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Unrestricted grammar
Kamis, 2025-12-11 03:41:36

the grammar. The latter problem is called the halting problem and is undecidable. Recursively enumerable languages are closed under Kleene star, concatenation...

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Tashi delek
Jumat, 2025-09-05 22:30:15

ISBN 978-0-86171-396-7 Oha, Obododimma (2008), "Language, Exile, and the Burden of Undecidable Citizenship: Tenzin Tsundue and the Tibetan Experience", in Allatson...

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P (complexity)
Minggu, 2026-01-18 10:36:55

some impractical problems, including some undecidable problems such as the unary version of any undecidable problem. In 1999, Jin-Yi Cai and D. Sivakumar...

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Ray tracing (graphics)
Kamis, 2026-03-26 14:28:26

inequalities is undecidable. Ray tracing in 3-D optical systems with a finite set of rectangular reflective or refractive objects is undecidable. Ray tracing...

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Textuality
Kamis, 2025-02-20 18:59:58

is that which constitutes a text in a particular way. The text is an undecidable (there is an inexistence of an effective or "strict" method of writing...

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N-sphere
Kamis, 2026-05-07 08:17:51

(6)/\operatorname {SO} (5)=\operatorname {SU} (3)/\operatorname {SU} (2)} ⁠. It is undecidable whether a given ⁠ n {\displaystyle n} ⁠-dimensional manifold is homeomorphic...

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Many-one reduction
Selasa, 2025-10-07 23:22:37

nonuniversal Turing machines whose individual halting problems are nevertheless undecidable. A polynomial-time many-one reduction from a problem A to a problem B...

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Busy beaver
Sabtu, 2026-06-06 00:15:10

that Σ is not a computable function. Moreover, this implies that it is undecidable by a general algorithm whether an arbitrary Turing machine is a busy...

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Enumeration
Selasa, 2026-05-26 17:49:07

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Knowledge-based engineering
Kamis, 2026-05-14 22:12:48

Order Logic, the more probable that it will allow expressions that are undecidable or require exponential processing power to complete. In the implementation...

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Well-formed formula
Minggu, 2026-03-01 20:20:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Joint spectral radius
Kamis, 2026-03-26 02:00:01

equal. Moreover, determining if ρ ≤ 1 {\displaystyle \rho \leq 1} is an undecidable problem. Nevertheless, in recent years much progress has been done on...

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Contradiction
Selasa, 2026-04-14 22:09:17

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Randomized algorithm
Selasa, 2026-04-28 21:04:17

concentration-based probability for which reaction will occur next) is undecidable. More specifically, a limited Turing machine can be simulated with arbitrarily...

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Turing completeness
Minggu, 2026-05-24 20:40:21

might contain the solution to the halting problem or some other Turing-undecidable problem. Such an infinite tape of data is called a Turing oracle. Even...

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Kleene Award
Kamis, 2024-09-19 00:08:58

Bounded Degree" 2021 Moritz Lichter and Jamie Tucker-Foltz 2022 Elena Di Lavore and Yoàv Montacute 2024 Søren Brinck Knudstorp "Relevant S is Undecidable"...

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Hierarchical task network
Rabu, 2024-08-07 17:50:12

planning is strictly more expressive than STRIPS, to the point of being undecidable in the general case. However, many syntactic restrictions of HTN planning...

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Dependent ML
Selasa, 2025-04-29 06:29:17

dependent types type checking remains decidable, but type inference becomes undecidable. Dependent ML has been superseded by ATS and is no longer under active...

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Axiom of adjunction
Senin, 2025-08-04 10:44:28

227–244, doi:10.1215/00294527-2009-009, MR 2572972 Tarski, Alfred (1953), Undecidable theories, Studies in Logic and the Foundations of Mathematics, Amsterdam:...

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General set theory
Kamis, 2026-06-04 08:29:06

is essentially undecidable because Q is, and every consistent theory whose theorems include the ST axioms is also essentially undecidable. This includes...

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John Myhill
Selasa, 2025-03-11 05:48:41

states that, for any nontrivial property P of partial functions, it is undecidable whether a given Turing machine computes a function with property P. The...

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Reduct
Kamis, 2024-05-09 09:03:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Two-variable logic
Selasa, 2022-09-13 20:07:22

fragment of first-order logic without function symbols, satisfiability is undecidable. The two-variable fragment of first-order logic with no function symbols...

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Element of a set
Senin, 2025-11-17 17:24:53

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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W. Hugh Woodin
Selasa, 2026-01-27 08:56:45

which suggested an argument that the continuum hypothesis is either undecidable or false in the sense of mathematical platonism. Woodin criticizes this...

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Unreachable code
Sabtu, 2026-05-02 09:53:51

is unreachable is at least as hard as the halting problem and hence undecidable Debray, Saumya K.; Evans, William; Muth, Robert; De Sutter, Bjorn (1...

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Soundness
Jumat, 2026-05-29 06:58:00

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Logical conjunction
Minggu, 2025-11-30 11:59:28

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Rounding
Selasa, 2026-05-26 13:01:32

calculated. Specific instances cannot be given but this follows from the undecidability of the halting problem. For instance, if Goldbach's conjecture is true...

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Abstract logic
Rabu, 2024-08-28 16:13:49

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Roaratorio
Jumat, 2026-06-05 03:55:51

2025-04-17. Froneman, Willemien (2010). "Composing According to Silence: Undecidability in Derrida and Cage's Roaratorio". IRASM. 41 (2): 293–317. Notes towards...

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Intuitionistic logic
Senin, 2026-05-04 04:59:49

{\displaystyle A} is provable. If a theory with the disjunction property has undecidable propositions, the excluded middle disjunctions of some excluded middle...

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Block cellular automaton
Jumat, 2026-01-09 15:42:53

automata with other non-block neighborhood structures, for which it is undecidable whether the automaton is reversible and for which the reverse dynamics...

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Agrippa the Skeptic
Selasa, 2026-05-12 23:43:33

of proofs. According to the mode deriving from dispute, we find that undecidable dissension about the matter proposed has come about both in ordinary...

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Double-negation translation
Senin, 2026-05-11 16:30:27

in English as "On Intuitionistic Arithmetic and Number Theory" in The Undecidable, edited by M. Davis, pp. 75–81. Kolmogorov, Andrey Nikolaevich (1925)...

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STIT logic
Selasa, 2026-02-10 19:44:26

fragments, showing for instance that many expressive group STIT logics are undecidable or of high computational complexity. In the 2010s, STIT ideas were combined...

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Topological manifold
Sabtu, 2026-05-09 08:23:32

the word problem in group theory, which is known to be algorithmically undecidable. In fact, there is no algorithm for deciding whether a given manifold...

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Unification (computer science)
Senin, 2026-02-09 02:58:32

exists (i.e., whether the complete substitution set is nonempty) is undecidable. The set S is called minimal if none of its members subsumes another...

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Quantifier (logic)
Minggu, 2026-04-12 18:13:39

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Unary language
Minggu, 2026-04-12 11:47:02

However, if membership in a language is undecidable, then membership in its unary version is also undecidable. TALLY is contained in P/poly—the class...

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List of mathematical proofs
Selasa, 2023-06-06 03:11:06

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Equality-generating dependency
Kamis, 2025-04-03 09:03:58

more generally, a set of EDs), and, if it terminates (which is a priori undecidable), output an instance that does satisfy the EGDs. An important subclass...

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Karl Svozil
Rabu, 2025-09-24 16:29:55

Media. ISBN 978-981-4021-07-4. Svozil, Karl (1993). Randomness and Undecidability in Physics. WORLD SCIENTIFIC. Bibcode:1993rup..book.....S. doi:10.1142/1524...

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Games, Puzzles, and Computation
Sabtu, 2025-12-27 14:22:52

the discovery that optimal play in certain multiplayer games can be an undecidable problem. A third part of the book provides a compendium of known hardness...

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Axiomatic system
Minggu, 2026-05-03 04:22:33

false by using the axioms. However, note that in some cases it may be undecidable if a statement can be proven or not. A model for an axiomatic system...

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Elementary function arithmetic
Selasa, 2025-10-14 00:46:26

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Generalized algebraic data type
Sabtu, 2026-02-14 12:35:01

inference in the absence of any programmer supplied type annotation, is undecidable and functions defined over GADTs do not admit principal types in general...

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NP (complexity)
Rabu, 2026-04-15 23:32:19

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Glossary of logic
Minggu, 2026-03-01 19:50:38

See temporal modal logic. Church's theorem A theorem establishing the undecidability of certain decision problems in logic, such as the Entscheidungsproblem...

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Markov chain
Selasa, 2026-04-28 08:12:47

minimization techniques, FSMs, Turing machines, Markov processes, and undecidability. Excellent treatment of Markov processes pp. 449ff. Discusses Z-transforms...

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Prime model
Selasa, 2025-12-02 07:29:59

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Setoid
Rabu, 2025-09-17 19:33:46

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Sous rature
Sabtu, 2026-05-23 16:07:36

concepts may be paradoxical or self-undermining, rendering their meaning undecidable. To extend this notion, deconstruction and the practice of sous rature...

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Completeness (logic)
Minggu, 2025-12-21 19:21:24

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Advice (complexity)
Minggu, 2025-09-21 02:56:47

(Adleman's theorem). It also contains some undecidable problems, such as the unary version of every undecidable problem, including the halting problem. Because...

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Automata theory
Rabu, 2026-05-06 19:19:46

 29–122. Section 4.1: Decidable Languages, pp. 152–159. Section 5.1: Undecidable Problems from Language Theory, pp. 172–183. Elaine Rich (2008). Automata...

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The Memory Wars
Senin, 2026-01-12 04:34:36

science makes him uncomfortable indeed with ambiguity, not to mention undecidability." Kahr called the book a "vicious piece of rhetoric" and argued that...

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S2S (mathematics)
Rabu, 2026-04-29 03:28:04

existential (i.e. Σ 1 1 {\displaystyle {\Sigma }_{1}^{1}} ) MSO theory is undecidable if we allow predicates on both vertices and edges. Thus, in a sense,...

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Range concatenation grammar
Jumat, 2025-11-28 11:58:25

the above is that it is undecidable whether a (positive) range concatenation language is nonempty, because it is undecidable whether the intersection...

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Venn diagram
Rabu, 2026-05-13 19:17:50

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Philosophical skepticism
Rabu, 2026-04-22 22:58:54

[UK]: Acumen. pp. 108–109. ISBN 978-1-84465-409-3. OCLC 715184861. Undecidability and the ten modes As part of his Pyrrhonian revival Aenesidemus assembled...

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Axiom of choice
Rabu, 2026-06-03 19:34:37

equivalent to the axiom of choice (that is, their truth values in ZF, while undecidable, are the same as that of AC). The most important among them are Zorn's...

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Intuitionistic type theory
Minggu, 2026-05-03 04:22:41

equality, which requires proof. As a consequence type checking becomes undecidable in extensional type theory because programs in the theory might not terminate...

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HRU (security)
Senin, 2026-04-27 20:51:52

configuration? They showed that there is no such algorithm, thus the problem is undecidable in the general case. They also showed a limitation of the model to commands...

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History of anarchism
Selasa, 2026-05-26 08:27:14

Springer. ISBN 978-3-319-75620-2. de Acosta, Alejandro (2009). "Two undecidable questions for thinking in which anything goes". In Randall Amster (ed...

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Computational problem
Kamis, 2025-07-17 11:19:42

problem will require, and explain why some problems are intractable or undecidable. Solvable computational problems belong to complexity classes that define...

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Symbol (formal)
Rabu, 2026-05-13 17:13:08

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Proof sketch for Gödel's first incompleteness theorem
Rabu, 2026-05-20 17:11:29

University Press: 596–616. Hirzel, Martin (trans.), 2000, "On formally undecidable propositions of Principia Mathematica and related systems I.". 1951,...

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Von Neumann universe
Jumat, 2026-05-29 03:10:10

10, no. 4 (2004). Accessed 21 August 2023. See article On Formally Undecidable Propositions of Principia Mathematica and Related Systems and Gödel 1931...

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Quantum mind
Jumat, 2026-03-13 17:42:46

Penguin Books. ISBN 0-14-01-4534-6. Gödel, Kurt (1992). On Formally Undecidable Propositions of Principia Mathematica and Related Systems (Reprint ed...

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Ordinal definable set
Jumat, 2026-01-16 06:37:17

Problems in Mathematics", in Davis, Martin (ed.), The undecidable. Basic papers on undecidable propositions, unsolvable problems and computable functions...

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Aperiodic tiling
Selasa, 2026-05-26 20:13:30

not decidable. This first such set, used by Berger in his proof of undecidability, required 20,426 Wang tiles. Berger later reduced his set to 104, and...

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Outline of algorithms
Rabu, 2026-05-06 22:19:54

(complexity) NP-completeness NP-hardness EXPTIME PSPACE BPP (complexity) BQP Undecidable problem Halting problem Rice's theorem No free lunch theorem List of...

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5-manifold
Selasa, 2024-06-11 16:59:12

isomorphism in second homology is induced by some diffeomorphism. It is undecidable if a given 5-manifold is homeomorphic to S 5 {\displaystyle S^{5}} ,...

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Set theory
Kamis, 2026-05-28 22:09:36

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Church–Turing–Deutsch principle
Rabu, 2026-03-04 21:39:52

of the principle was given by Stephen Wolfram in February 1985. In Undecidability and Intractability in Theoretical Physics , Wolfram wrote that "[U]niversal...

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Hilbert system
Jumat, 2026-05-22 19:44:20

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Function-level programming
Senin, 2026-01-26 08:13:10

equality of two functions is equivalent to the halting problem, and is undecidable, but equality of two functions in FP is just equality in the algebra...

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Large cardinal
Selasa, 2026-05-12 14:54:27

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Zorn's lemma
Minggu, 2026-05-24 10:41:20

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Free logic
Selasa, 2025-12-23 00:06:35

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Lenin Prize
Sabtu, 2026-03-28 11:11:39

(1957, space science) Pyotr Novikov (1957, mathematics, for proving the undecidability of the word problem for groups) Sergei Prokofiev (1957, music, posthumously...

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Ignoramus et ignorabimus
Senin, 2025-11-24 07:22:24

few, most notably Cantor's continuum hypothesis, have been shown to be undecidable on the basis of currently accepted principles. In 1931, Gödel's incompleteness...

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Andrzej Mostowski
Jumat, 2026-04-17 04:33:58

foundations of mathematics. His work was largely on recursion theory and undecidability. From 1946 until his death in Vancouver, British Columbia, Canada, he...

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Natural deduction
Jumat, 2026-03-06 22:02:16

earlier sections was decidable, adding the quantifiers makes the logic undecidable. So far, the quantified extensions are first-order: they distinguish...

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List of conjectures
Minggu, 2026-05-17 12:56:48

unsolved problems List of lemmas List of theorems List of statements undecidable in ZFC Weisstein, Eric W. (2002). CRC Concise Encyclopedia of Mathematics...

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Identity type
Jumat, 2026-04-24 23:01:36

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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AI alignment
Kamis, 2026-06-04 01:28:43

Nei Y.; Castro, Paulo A. L. (2025). "Machines that halt resolve the undecidability of artificial intelligence alignment". Scientific Reports. 15 (1): 15591...

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Gödel's completeness theorem
Jumat, 2026-02-06 16:01:03

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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LL grammar
Kamis, 2023-12-07 17:49:43

LL(k) and LR(k) parsers, the problem of generating an LLR/LRR parser is undecidable unless one has constructed a regular partition upfront. But even the...

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Atomic model (mathematical logic)
Senin, 2026-05-18 04:04:51

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Countable set
Kamis, 2026-06-04 04:51:27

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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History of the Church–Turing thesis
Minggu, 2025-09-21 05:35:35

what he called "P" (nowadays called Peano Arithmetic), "there exist undecidable sentences [propositions]". Because of this, "the consistency of P is...

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Paul Erdős
Selasa, 2026-06-02 16:48:55

ISBN 978-0-387-74640-1 Kurtz, Stuart A.; Simon, Janos (2007). "The Undecidability of the Generalized Collatz Problem". In Cai, Jin-Yi; Cooper, S. Barry;...

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Word equation
Sabtu, 2026-03-07 22:13:21

number theory. One stark difference is that Diophantine equations have an undecidable solubility problem, whereas the analogous problem for word equations...

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Referential integrity
Kamis, 2025-08-28 00:20:35

dependencies that can be inclusion dependencies or functional dependencies is undecidable by reduction from the word problem for monoids. Declarative referential...

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Metalogic
Sabtu, 2026-05-16 11:37:35

Decidability of first-order monadic predicate logic (Leopold Löwenheim 1915) Undecidability of first-order predicate logic (Church's theorem 1936) Other important...

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Predicate functor logic
Senin, 2025-12-01 22:40:46

interpreted predicate letters: both logics are sound, complete, and undecidable. Most work Quine published on logic and mathematics in the last 30 years...

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Kőnig's theorem (set theory)
Selasa, 2026-06-02 20:26:35

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Wells Fargo Center (Los Angeles)
Minggu, 2026-05-24 09:35:15

whose putative volume (rectangular, trapezoidal?) is ocularly quite undecidable. This great sheet of windows, with its gravity-defying two-dimensionality...

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RE (complexity)
Sabtu, 2025-07-12 17:02:45

LL}}-({\mbox{RE}}\cup {\mbox{co-RE}})} . Not only are these problems undecidable, but neither they nor their complement are recursively enumerable. In...

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Material conditional
Senin, 2026-03-23 20:50:38

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Rasiowa–Sikorski lemma
Selasa, 2026-01-20 01:50:30

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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O-minimal theory
Kamis, 2026-05-07 21:20:28

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Logical framework
Selasa, 2026-03-24 14:12:42

property of being well-typed is decidable. However, type inference is undecidable. A logic is represented in the LF logical framework by the judgements-as-types...

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HNN extension
Sabtu, 2025-12-06 23:08:24

about the existence of a finitely presented group with algorithmically undecidable word problem also substantially use HNN-extensions. The idea of HNN extension...

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Infinite set
Minggu, 2025-09-28 17:06:10

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Parametric polymorphism
Jumat, 2025-09-19 08:54:37

For instance, type inference for rank-3 and above system F remains undecidable (as detailed above), however, for intersection types, type inference...

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Propositional logic
Selasa, 2026-04-21 03:02:31

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Semantic theory of truth
Selasa, 2026-02-24 10:37:34

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Nonelementary integral
Selasa, 2026-04-28 09:02:35

integration in terms of elementary functions Richardson's theorem – Undecidability of equality of real numbers Symbolic integration – Computation of an...

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1936
Senin, 2026-06-01 23:19:36

May 28 - Alan Turing submits "On Computable Numbers", proving the undecidability of the Halting problem and the decision problem for logic. Computer...

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Structure (mathematical logic)
Rabu, 2026-05-06 00:05:31

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Taylor Booth (mathematician)
Kamis, 2025-08-07 11:12:36

techniques, finite-state machines, Turing machines, Markov processes, and undecidability. Booth studied at the University of Connecticut, where he received his...

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Zermelo–Fraenkel set theory
Selasa, 2026-06-02 08:55:27

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Diophantine set
Minggu, 2025-11-16 12:45:26

shown that the question of solvability of a Diophantine equation is undecidable even if the equation only has 9 natural number variables (Matiyasevich...

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Literary theory
Senin, 2026-05-18 05:47:50

concepts may be paradoxical or self-undermining, rendering their meaning undecidable Jacques Derrida, Paul de Man, J. Hillis Miller, Philippe Lacoue-Labarthe...

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Turing reduction
Minggu, 2026-05-17 21:52:13

possible that B is an undecidable problem for which no algorithm exists. M. Davis, ed., 1965. The Undecidable—Basic Papers on Undecidable Propositions, Unsolvable...

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F-logic
Rabu, 2025-12-31 02:21:54

in contrast to DL's open world assumption. Also, F-logic is generally undecidable,[citation needed] whereas the SHOIN description logic that Web Ontology...

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Interior algebra
Sabtu, 2025-06-14 23:33:59

closure algebras undecidable. Naturman demonstrated that the theory is hereditarily undecidable (all its subtheories are undecidable) and demonstrated...

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Séminaire Nicolas Bourbaki (1960–1969)
Rabu, 2023-07-26 03:04:13

(locally symmetric spaces) Daniel Lacombe, Théorèmes de non-décidabilité (undecidability) Pierre Samuel, Travaux d'Igusa sur les formes modulaires de genre 2...

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Jewish Babylonian Aramaic
Kamis, 2026-03-05 06:41:03

technical logic terms such as tiyuvta "conclusive refutation" and tiqu "undecidable moot point", which are still used in Jewish legal writings, including...

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Separation logic
Senin, 2026-04-06 04:34:20

locations can also be shown to be PSPACE-complete, whereas the problem is undecidable with interpreted memory locations (e.g., integers) or further quantifier...

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Functional programming
Kamis, 2026-05-14 03:35:30

unrestricted recursion and are Turing complete, which makes the halting problem undecidable, can cause unsoundness of equational reasoning, and generally requires...

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Consistency model
Jumat, 2026-04-03 23:12:09

consistency. Verifying sequential consistency through model checking is undecidable in general, even for finite-state cache coherence protocols. Causal consistency...

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Computable function
Senin, 2026-02-23 00:00:04

the London Mathematical Society, Series 2, Volume 42 (1937), p.230–265. Reprinted in M. Davis (ed.), The Undecidable, Raven Press, Hewlett, NY, 1965....

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Implementation of mathematics in set theory
Selasa, 2025-11-18 01:01:03

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Subtyping
Jumat, 2025-10-17 03:27:50

supertypes in some contract. This definition of subtyping is generally undecidable, so it cannot be verified by a type checker. The subtyping of mutable...

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Cantor's diagonal argument
Sabtu, 2026-04-18 21:27:42

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Hopfian group
Jumat, 2024-06-07 02:36:56

it is an undecidable problem to determine, given a finite presentation of a group, whether the group is Hopfian. Unlike the undecidability of many properties...

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Formal proof
Sabtu, 2026-05-16 11:40:13

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Hybrid automaton
Jumat, 2024-12-20 23:07:17

automata it is not surprising that simple reachability questions are undecidable for general hybrid automata. In fact, a straightforward reduction from...

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Petri net
Sabtu, 2026-01-24 21:22:30

empties the place when the transition fires; this makes reachability undecidable, while some other properties, such as termination, remain decidable;...

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Quantum nonlocality
Kamis, 2026-05-21 11:59:12

quantum box can have a perfect score at a non-local game is known to be undecidable. Moreover, the problem of deciding whether P ( a , b | x , y ) {\displaystyle...

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Cathy Edwards (software engineer)
Jumat, 2026-01-02 01:10:15

Edwards left Apple in April 2014 and founded a new stealth startup Undecidable Labs in 2015 with some ex-Chomp colleagues which was acquired by Google...

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Malament–Hogarth spacetime
Jumat, 2025-10-31 23:40:27

set-up can be used to decide the halting problem, which is known to be undecidable by an ordinary Turing machine. All the observer needs to do is to prime...

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Stable theory
Selasa, 2026-04-28 21:07:11

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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P/poly
Selasa, 2026-01-20 05:44:53

considered a practical class for computing. Indeed, it contains every undecidable unary language, none of which can be solved in general by real computers...

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Fitch's paradox of knowability
Senin, 2025-10-20 14:02:40

mathematics (e.g. Peano Arithmetic), there are statements which are undecidable. In that context, it is difficult to state that "all truths are knowable"...

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Context-free language
Sabtu, 2026-05-09 23:03:24

equivalent to a language with a different grammar. The following problems are undecidable for arbitrarily given context-free grammars A and B: Equivalence: is...

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Chaitin's constant
Senin, 2026-04-27 12:02:24

problem for programs of length up to n. Since the halting problem is undecidable, Ω cannot be computed. The algorithm proceeds as follows. Given the first...

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Timeline of artificial intelligence
Kamis, 2026-06-04 10:29:29

He used it to confirm Gödel by proving that the halting problem is undecidable. 1940 Edward Condon displayed Nimatron, a digital machine that played...

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History of mathematical notation
Senin, 2026-05-25 03:48:30

Truth, would be a falsity, an insanity.) Proposition VI, On Formally Undecidable Propositions in Principia Mathematica and Related Systems I (1931) Casti...

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Logical biconditional
Rabu, 2026-03-11 08:01:05

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Set (mathematics)
Rabu, 2026-05-06 05:45:09

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Vadalog
Minggu, 2026-03-29 01:02:54

answer to the program. If arbitrary propagation is allowed, reasoning is undecidable and the program will be infinite. Warded Datalog± overcomes this issue...

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Equality (mathematics)
Rabu, 2026-04-22 06:34:05

the equality of two real numbers given by an expression is known to be undecidable (specifically, real numbers defined by expressions involving the integers...

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Philosophy of mathematics
Kamis, 2026-04-30 08:29:02

studies Scientific method The Analyst Euclid's Elements "On Formally Undecidable Propositions of Principia Mathematica and Related Systems" "On Computable...

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Constrained Horn clauses
Senin, 2025-08-11 17:29:06

constrained Horn clauses with constraints from linear integer arithmetic is undecidable. There are several automated solvers for CHCs, including the SPACER engine...

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Schröder–Bernstein theorem
Rabu, 2026-05-20 23:09:01

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Semantics (logic)
Senin, 2026-04-20 08:59:01

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Constructivism (philosophy of mathematics)
Selasa, 2026-05-05 18:04:29

disproof of Goldbach's conjecture must exist (the conjecture may be undecidable in traditional ZF set theory). Thus to Brouwer, we are not justified...

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Double pushout graph rewriting
Rabu, 2025-07-23 07:48:41

structures than graphs is chosen). Termination for DPO graph rewriting is undecidable because the Post correspondence problem can be reduced to it. DPO graph...

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Analytic philosophy
Jumat, 2026-05-29 23:30:15

121–123. doi:10.1093/analys/23.6.121. Gödel, Kurt (1931). On Formally Undecidable Propositions of Principia Mathematica and Related Systems. Basic Books...

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Algebra of sets
Selasa, 2026-05-19 07:17:41

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Truth table
Jumat, 2026-06-05 17:53:51

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Viable system model
Rabu, 2025-12-10 08:09:48

This defines a metalanguage stack of increasing capability to resolve undecidability in the autonomous lower levels. If someone near process level needs...

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Finitary relation
Rabu, 2026-05-06 13:19:05

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Apartness relation
Senin, 2025-11-17 13:48:52

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Logical disjunction
Minggu, 2025-10-19 00:36:10

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Science Without Numbers
Senin, 2026-06-08 07:19:41

theory. Furthermore, under Field's nominalization, statements that are undecidable in standard set theory like the continuum hypothesis become statable...

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Bisimulation
Jumat, 2026-01-23 17:27:24

ISBN 978-0-262-02649-9. LCCN 2007037603. Jančar, Petr; Srba, Jiří (2008). "Undecidability of Bisimilarity by Defender's Forcing". J. ACM. 55 (1). New York, NY...

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Second-order logic
Kamis, 2026-04-02 00:04:18

{N} } ,+)) can interpret the true second-order arithmetic and is thus undecidable. Just as in first-order logic, second-order logic may include non-logical...

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Formal system
Sabtu, 2026-05-30 21:23:31

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Characteristic samples
Rabu, 2025-10-15 02:02:12

{\displaystyle L\in \mathbb {C} } has a characteristic sample. If equivalence is undecidable for a class C {\textstyle \mathbb {C} } over Σ {\textstyle \Sigma } of...

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Gentzen's consistency proof
Senin, 2025-09-15 22:35:21

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Arity
Senin, 2026-02-09 06:30:10

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Fastest
Selasa, 2025-09-16 19:39:40

determine if the predicate is a contradiction or not. Since this problem is undecidable, the tool implements a best-effort algorithm that can be improved by...

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Joel David Hamkins
Jumat, 2026-03-13 20:25:36

proved that the classical halting problem for Turing machines, although undecidable, is nevertheless decidable on a set of asymptotic probability one, one...

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Constant problem
Rabu, 2025-06-04 07:57:35

that a given expression is non-zero, or of showing that the problem is undecidable. For example, if x1, ..., xn are real numbers, then there is an algorithm...

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Computably inseparable
Jumat, 2025-07-04 02:09:55

Springer-Verlag, ISBN 978-0-387-90170-1 Smullyan, Raymond M. (1958), "Undecidability and recursive inseparability", Zeitschrift für Mathematische Logik und...

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List of publications in philosophy
Kamis, 2026-04-23 20:42:51

Whitehead, Principia Mathematica, 1910–13/1925–27 Kurt Gödel, "On Formally Undecidable Propositions of Principia Mathematica and Related Systems", 1931 Alfred...

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First-class function
Jumat, 2026-01-16 13:55:08

sort, would be considered equal. Deciding on extensional equality is undecidable in general and even for functions with finite domains often intractable...

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Tautology (logic)
Jumat, 2026-05-29 09:09:20

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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History of computing hardware
Jumat, 2026-06-05 16:21:31

Entscheidungsproblem by first showing that the halting problem for Turing machines is undecidable: in general, it is not possible to decide algorithmically whether a given...

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Word Processing in Groups
Jumat, 2025-12-26 20:06:51

was eventually stymied by the phenomenon that many basic problems are undecidable. Despite tracing the origins of automatic groups to early 20th-century...

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List of pioneers in computer science
Kamis, 2026-05-21 02:28:05

known as the Church-Turing Thesis and proved that first-order logic is undecidable. 1962 Clark, Wesley A. Designed LINC, the first functional computer scaled...

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Mathematical structure
Selasa, 2026-04-07 07:01:58

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Finite-state transducer
Sabtu, 2026-03-14 22:08:00

string y such that x[T]y for a given string x.[citation needed] It is undecidable whether two transducers are equivalent. Equivalence is however decidable...

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Beth number
Rabu, 2026-04-22 06:33:15

{\displaystyle \beth _{\alpha }} can exist. (In that case, the existence is undecidable in ZFC and controlled by the Generalized Continuum Hypothesis.) Even...

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Aczel's anti-foundation axiom
Sabtu, 2026-04-18 14:59:43

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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C-minimal theory
Jumat, 2025-03-07 04:56:51

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Type inhabitation
Senin, 2025-03-24 10:39:52

PSPACE-complete. For other calculi, like System F, the problem is even undecidable. Curry–Howard isomorphism Pawel Urzyczyn (1997). "Inhabitation in typed...

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Newton da Costa
Rabu, 2026-05-20 00:04:03

properties of those systems are undecidable and Gödel-incomplete, that is, a sentence like X is chaotic is undecidable within that axiomatics. They later...

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Supertask
Jumat, 2026-05-22 00:54:07

propositions of number theory, such as Goldbach's conjecture, or even undecidable propositions could be determined in a finite amount of time by a brute-force...

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Type variance
Kamis, 2026-04-23 23:14:04

termination, type argument inference, and ambiguous programs. In general it is undecidable whether a Java program using generics is well-typed or not, so any type...

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Union (set theory)
Kamis, 2026-04-02 16:15:25

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Linear logic
Senin, 2026-05-11 06:44:12

denotes unconsumable resources. The entailment relation in full CLL is undecidable. When considering fragments of CLL, the decision problem has varying...

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Successor cardinal
Sabtu, 2026-01-24 15:01:34

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Uncountable set
Selasa, 2026-05-26 07:31:54

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Reversible cellular automaton
Kamis, 2025-11-27 11:47:23

cellular automata and for one-dimensional cellular automata, but is undecidable for other types of cellular automata. Reversible cellular automata form...

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Gödel's β function
Jumat, 2026-01-23 04:35:31

Press, ISBN 0-19-853189-3. Martin Davis, ed. (1965). The Undecidable – Basic Papers on Undecidable Propositions, Unsolvable Problems and Computable Functions...

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Heyting arithmetic
Rabu, 2026-06-03 19:23:19

to applications of double-negation elimination. In particular, with undecidable atomic propositions being absent, for any proposition ψ {\displaystyle...

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Tarski's axioms
Selasa, 2026-02-03 11:16:15

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Next-bit test
Rabu, 2025-01-29 21:41:16

cannot be derived from this case (since it involves deciding potentially undecidable problems), but the proof of Adleman's theorem can be easily adapted to...

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Function symbol
Kamis, 2025-10-09 12:05:23

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Linear network coding
Sabtu, 2026-05-09 04:31:34

with arbitrary demands is a hard problem, which can be NP-hard and even undecidable. In a linear network coding problem, a group of nodes P {\displaystyle...

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Technics and Time, 1
Jumat, 2025-04-18 17:25:47

between the human and the technical, the "who" and the "what" are in an undecidable relation. Part II is largely a reading of the work of Martin Heidegger...

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Algorithm characterizations
Senin, 2026-05-04 13:20:51

provable formulas . . . ." (p. 72 in Martin Davis ed. The Undecidable: "Postscriptum" to "On Undecidable Propositions of Formal Mathematical Systems" appearing...

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Steve Omohundro
Jumat, 2025-08-15 11:49:22

automata. The asymptotic behavior of these PDEs is therefore logically undecidable. With John David Crawford he showed that the orbits of three-dimensional...

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History of logic
Sabtu, 2026-03-14 00:04:28

Church proved additional undecidability results, showing that both Peano arithmetic and first-order logic are undecidable. Later work by Emil Post and...

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Subtraction game
Minggu, 2026-02-01 11:30:48

vectors can have positive as well as negative coefficients, it is an undecidable problem to determine whether two such games have the same P-positions...

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Anne Condon
Jumat, 2026-01-30 05:32:52

403 pages 175–179, 2000. O. Madani, A. Condon, and S. Hanks, "On the Undecidability of Probabilistic Planning and Infinite-Horizon Partially Observable...

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Term logic
Sabtu, 2026-05-23 19:41:16

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Size-change termination principle
Minggu, 2023-08-13 17:19:01

whether a program will halt on a particular input, or on all inputs, is undecidable. Therefore, a general algorithm for proving any program to halt does...

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Philosophy of religion
Sabtu, 2026-04-04 19:51:29

is justified if one is presented with a question which is rationally undecidable and if one is presented with genuine and live options which are relevant...

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Map (mathematics)
Selasa, 2026-06-02 04:42:13

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Stratification (mathematics)
Rabu, 2026-03-18 22:58:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Eva Miranda
Senin, 2026-06-01 05:43:31

Daniel Peralta-Salas and collaborators, she showed the existence of undecidable fluid paths, linking computer science, differential geometry, and fluid...

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Aleph number
Senin, 2026-05-04 19:14:22

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Beth definability
Kamis, 2026-03-26 07:55:33

enumerable Computable function Computable set Decision problem decidable undecidable P NP P versus NP problem Kolmogorov complexity Lambda calculus Primitive...

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Geoffrey K. Pullum
Sabtu, 2026-02-14 10:04:27

Geoffrey K. (2000) "Scooping the loop snooper: An elementary proof of the undecidability of the halting problem". Mathematics Magazine 73.4 (October 2000), 319–320...

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PP (complexity)
Jumat, 2026-02-13 02:20:43

given a description of a polynomial-time probabilistic machine, it is undecidable in general to determine if it recognizes a language in BPP. PP has natural...

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