Undecidable problems | Theory of computation | Computability theory

List of undecidable problems

In computability theory, an undecidable problem is a type of computational problem that requires a yes/no answer, but where there cannot possibly be any computer program that always gives the correct answer; that is, any possible program would sometimes give the wrong answer or run forever without giving any answer. More formally, an undecidable problem is a problem whose language is not a recursive set; see the article Decidable language. There are uncountably many undecidable problems, so the list below is necessarily incomplete. Though undecidable languages are not recursive languages, they may be subsets of Turing recognizable languages: i.e., such undecidable languages may be recursively enumerable. Many, if not most, undecidable problems in mathematics can be posed as word problems: determining when two distinct strings of symbols (encoding some mathematical concept or object) represent the same object or not. For undecidability in axiomatic mathematics, see List of statements undecidable in ZFC. (Wikipedia).

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C61 Another problem involving free undamped motion

Another example problem involving damped harmonic motion.

From playlist Differential Equations

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A14 Nonhomegeneous linear systems solved by undetermined coefficients

There are two methods for solving nonhomogeneous systems. The first uses undetermined coefficients.

From playlist A Second Course in Differential Equations

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C55 Example problem of free undamped motion

Solving a problem of free undamped harmonic motion.

From playlist Differential Equations

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Differential Equations | Undetermined Coefficients for a System of DEs

We use the method of undetermined coefficients to solve a nonhomogeneous system of first order linear differential equations. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Systems of Differential Equations

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B06 Example problem with separable variables

Solving a differential equation by separating the variables.

From playlist Differential Equations

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Equilateral Triangles Problem

GeoGebra Link: https://www.geogebra.org/m/f5zgupmz

From playlist Geometry: Challenge Problems

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B07 Example problem with separable variables

Solving a differential equation by separating the variables.

From playlist Differential Equations

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Undecidability and CFLs

Theory of Computation 10. Undecidability and CFLs ADUni

From playlist [Shai Simonson]Theory of Computation

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Barry Mazur - Logic, Elliptic curves, and Diophantine stability

This is the first lecture of the 2014 Minerva Lecture series at the Princeton University Mathematics Department October 14, 2014 An introduction to aspects of mathematical logic and the arithmetic of elliptic curves that make these branches of mathematics inspiring to each other. Specif

From playlist Minerva Lectures - Barry Mazur

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Turing Meets Paradoxes (History of Undecidability Part 3) - Computerphile

Taking a solemn oath to promise never to write a program that analyses other programs? - That's how Professor Brailsford felt when he first understood undecidability. Latest in our series on the History of Undecidability Undecidability Tangent (History of Undecidability Part 1): http://y

From playlist The History of Undecidability

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8. Undecidability

MIT 18.404J Theory of Computation, Fall 2020 Instructor: Michael Sipser View the complete course: https://ocw.mit.edu/18-404JF20 YouTube Playlist: https://www.youtube.com/playlist?list=PLUl4u3cNGP60_JNv2MmK3wkOt9syvfQWY Quickly reviewed last lecture. Showed that natural numbers and real n

From playlist MIT 18.404J Theory of Computation, Fall 2020

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The Halting Problem

Theory of Computation 13. The Halting Problem aduni

From playlist [Shai Simonson]Theory of Computation

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Alexandra SHLAPENTOKH - Defining Valuation Rings and Other Definability Problems in Number Theory

We discuss questions concerning first-order and existential definability over number fields and function fields in the language of rings and its extensions. In particular, we consider the problem of defining valuations rings over finite and infinite algebraic extensions

From playlist Mathematics is a long conversation: a celebration of Barry Mazur

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Diophantine approximation and Diophantine definitions - Héctor Pastén Vásquez

Short Talks by Postdoctoral Members Héctor Pastén Vásquez - September 29, 2015 http://www.math.ias.edu/calendar/event/88264/1443549600/1443550500 More videos on http://video.ias.edu

From playlist Short Talks by Postdoctoral Members

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Are These Batteries The Future Of Energy Storage?

Are These Batteries The Future Of Energy Storage? See why hiring doesn’t have to be difficult — when you try ZipRecruiter for free at https://www.ziprecruiter.com/UNDECIDED. There’s a huge number of lithium-ion battery alternatives in the works … so many that it can be hard to keep track o

From playlist Battery technology

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The Truth About Plastic Recycling ... It’s Complicated

The Truth About Plastic Recycling. The first 100 people to use code UNDECIDED at the link below will get 20% off of Incogni: https://incogni.com/undecided Is it a scam? It's complicated. The 3R’s: reduce, reuse, recycle has been drilled into our heads as the way forward towards a sustainab

From playlist The truth about

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B05 Example problem with separable variables

Solving a differential equation by separating the variables.

From playlist Differential Equations

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Computably enumerable sets and undecidability

In this video we're going to define and implement decidable as well as semidecidable. Code is found under https://gist.github.com/Nikolaj-K/808149debf7c3b09705127f9205f6c3f Other names for the two are recursive or computable resp. recursively enumerable, computably enumerable - I also say

From playlist Programming

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