Undecidable problems | Formal languages | Polynomial-time problems | PSPACE-complete problems

Emptiness problem

In theoretical computer science and formal language theory, a formal language is empty if its set of valid sentences is the empty set. The emptiness problem is the question of determining whether a language is empty given some representation of it, such as a finite-state automaton. For an automaton having states, this is a decision problem that can be solved in time. However, variants of that question, such as the emptiness problem for non-erasing stack automata, are PSPACE-complete. The emptiness problem is undecidable for context-sensitive grammars, a fact that follows from the undecidability of the halting problem. It is, however, decidable for context-free grammars. (Wikipedia).

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Does space mean emptiness? How do you describe it?

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From playlist Science Unplugged: Physics

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Determine Where the Function is Not Continuous

In this video I will show you how to Determine Where the Function is Not Continuous.

From playlist Continuity Problems

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Removable and Nonremovable Discontinuities in a Rational Function Calculus Example

In this video I do an example of finding Removable and Nonremovable Discontinuities in a Rational Function.

From playlist Continuity Problems

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How does the Higgs field affect the notion of empty space?

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From playlist Science Unplugged: Higgs Particle

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Examples of removable and non removable discontinuities to find limits

👉 Learn how to classify the discontinuity of a function. A function is said to be discontinuos if there is a gap in the graph of the function. Some discontinuities are removable while others are non-removable. There is also jump discontinuity. A discontinuity is removable when the denomin

From playlist Holes and Asymptotes of Rational Functions

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What is infinity?

What’s the biggest number you can think of? Well, what about one more than that number? We can’t really comprehend the idea of infinity, but it’s still a useful concept in science. Brian Greene explains more. Subscribe to our YouTube Channel for all the latest from World Science U. Visit

From playlist Science Unplugged: Physics

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Touching Infinity: It's Not Out of Reach

The conventional way to represent the Real Number system is to think of the numbers as corresponding to points along an infinite straight line. The problem is that in this representation there is no place for "infinity". Infinity is not a real number. This video shows an alternate visua

From playlist Lessons of Interest on Assorted Topics

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Is the nothing of a black hole the same as empty space?

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From playlist Science Unplugged: Black Holes

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9. Reducibility

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. Discussed the reducibility method to p

From playlist MIT 18.404J Theory of Computation, Fall 2020

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Extremal Combinatorics with Po-Shen Loh - 04/13 Mon

Carnegie Mellon University is protecting the community from the COVID-19 pandemic by running courses online for the Spring 2020 semester. This is the video stream for Po-Shen Loh’s PhD-level course 21-738 Extremal Combinatorics. Professor Loh will not be able to respond to questions or com

From playlist CMU PhD-Level Course 21-738 Extremal Combinatorics

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PotW: Marking the Grid [Configurations]

If this video is confusing, be sure to check out our blog for the full solution transcript! https://centerofmathematics.blogspot.com/2017/10/problem-of-week-10-10-17-marking-grid.html

From playlist Center of Math: Problems of the Week

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O'Reilly Webcast: Nullology: The Zen of Database

Nullology is the study of the empty set. Of course, sets crop up all over the place in the database world; but the question is--and it's a crucial one--what happens if the set under consideration happens to be empty? For example, a relation contains a set of tuples: what about the possibil

From playlist O'Reilly Webcasts

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Finite Intersection Property

In this video, I discuss the finite intersection property, which is a nice generalization of the Cantor Intersection Theorem and a very elegant application of compactness. Enjoy this topology-filled adventure! Compactness: https://youtu.be/xiWizwjpt8o Cantor Intersection Theorem: https:/

From playlist Topology

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PHP Tutorial | How To Create Hotel Booking Web App In PHP | Session 07 | #programming

Don’t forget to subscribe! In this project series, you will learn to create a hotel booking web app in PHP. This tutorial will cover all the details (resources, tools, languages, etc.) that are necessary to build a complete and operational Hotel Booking web app. You will be guided throu

From playlist Create Hotel Booking Web App In PHP

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Power Set of the Power Set of the Power Set of the Empty Set

We find the power set of the power set of the empty set, as well as the power set of the power set of the power set of the empty set. Nice problem I think. If you enjoyed this video please consider liking, sharing, and subscribing. Udemy Courses Via My Website: https://mathsorcerer.com

From playlist Set Theory

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22: The most important thing - Richard Buckland UNSW

The challenge: can we write a Sudoku solver in a single lecture? What is a sudoku puzzle? Estimation revisited. how to solve a problem - difference between the approach of a master and a novice. What is the most important thing? Also: How to lie with statistics. hang gliding.

From playlist CS1: Higher Computing - Richard Buckland UNSW

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Decidability

Theory of Computation 14. Decidability ADUni

From playlist [Shai Simonson]Theory of Computation

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Removable or Nonremovable Discontinuity Example with Absolute Value

Removable or Nonremovable Discontinuity Example with Absolute Value

From playlist Calculus 1 Exam 1 Playlist

Related pages

Big O notation | PSPACE-complete | Context-sensitive grammar | Undecidable problem | Theoretical computer science | Decision problem | Halting problem | Empty set | Context-free grammar