'Decidable' presentation slideshows

Lecture 4: Unsolvable Problems

Lecture 4: Unsolvable Problems. ???. ??????? ?????????. Content. Enumerable and Decidable Sets Algorithm Solvability Problem Reduction Diagonalization Method. Lecture 4: Unsolvable Problems. Enumerable and Decidable Sets. ??????? ?????????. Set Enumerability and Generability.

988 views • 89 slides

Developing distributed protocols formally with Ivy

Developing distributed protocols formally with Ivy. Ken McMillan Microsoft Research. Joint work with: Marcelo Taube, Giuliano Losa, Oded Padon, Mooly Sagiv, Sharon Shoham, James R. Wilcox, Doug Woos. Motivation. How effective is the use of automation in proofs of distributed systems?.

705 views • 69 slides

Introduction to Computability Theory

Introduction to Computability Theory. Lecture12: Reductions Prof. Amos Israeli. Introduction. The rest of the course deals with an important tool in Computability and Complexity theories, namely: Reductions .

784 views • 63 slides

Overview

535 views • 41 slides

CS21 Decidability and Tractability

CS21 Decidability and Tractability. Lecture 11 February 1, 2019. Outline. Church-Turing Thesis decidable, RE, co-RE languages the Halting Problem reductions many-one reductions. Undecidability. decidable. decidable RE all languages our goal: prove these containments proper.

421 views • 35 slides

A Perspective on Graphs and Access Control Models

A Perspective on Graphs and Access Control Models. Ravi Sandhu Laboratory for Information Security Technology George Mason University www.list.gmu.edu sandhu@gmu.edu. Outline. A perspective on security A perspective on access control The safety problem in access control Looking ahead

283 views • 28 slides

MA/CSSE 474 Theory of Computation

MA/CSSE 474 Theory of Computation. More Reduction Examples Non-SD Reductions. Your Questions?. HW 15 problems Final Exam Anything else. Previous class days' material Reading Assignments. Excerpt from an obituary in the Terre Haute Tribune Star . May 12, 2018:.

244 views • 24 slides

4. Decidability

4. Decidability. The diagonalization method The halting problem is undecidable co-HALT is unrecognizable. Undecidability. decidable. all languages. decidable ? RE ? all languages our goal: prove these containments proper. regular languages. context free languages. RE.

453 views • 23 slides

Theory of Computing

Theory of Computing. Lecture 20 MAS 714 Hartmut Klauck. Decidability. Definition: A language is decidable if there is a TM that accepts all words in the language and rejects all words not in the language In particular it always halts in finite time

318 views • 22 slides

Decidability

Decidability. A decision problem is a problem for which the answer is either "yes" or "no". A decidable problem is a decision problem that has a solution algorithm. A semidecidable problem is a decision problem for which there is a decision procedure

885 views • 21 slides

Chapter 3: Foundational Results

Chapter 3: Foundational Results. Overview Harrison-Ruzzo-Ullman result Corollaries. Overview. Safety Question HRU Model. The general question. How can we determine whether a system is safe? Is there a generic algorithm that will determine whether a system is safe?.

294 views • 21 slides

CSCI 2670 Introduction to Theory of Computing

CSCI 2670 Introduction to Theory of Computing. October 19, 2004. Agenda. Last week Variants of Turing machines Definition of algorithm This week Chapter 4 Decidable and undecidable languages The halting problem. Announcements. Homework due next Tuesday (10/26)

385 views • 18 slides

Event-Clock Visibly Pushdown Automata

Event-Clock Visibly Pushdown Automata. Mizuhito Ogawa (JAIST) with Nguyen Van Tang SOFSEM 2009.1.27. OK. Model checking as an inclusion problem. Paths generated by a model M is those that allowed by a specification S L( M ) ? L( S ) ? L( M ) ? L( S ) C = ? Possible combinations

275 views • 17 slides

COSC 3340: Introduction to Theory of Computation

COSC 3340: Introduction to Theory of Computation. University of Houston Dr. Verma Lecture 27. Diagonalization Principle. Let S be any nonempty set and R any relation on S . The principle states that: the complement of the diagonal is different from each row.

147 views • 14 slides

Computation

Computation. Chapter 4. Computational Issues. Goal of the book: be able to make useful claims about problems and the programs that solve them. cast problems as language recognition tasks define programs as state machines whose input is a string and output is Accept or Reject

226 views • 12 slides

Undecidability and The Halting Problem

Undecidability and The Halting Problem. CS 130 Theory of Computation HMU Textbook: Chap 9. Problems and Languages. Decision problems can be captured as languages Example:

340 views • 12 slides

Lecture 7 Undecidability cont.

Lecture 7 Undecidability cont. Jan Maluszynski , IDA, 200 7 http://www.ida.liu.se/~janma. Outline. (Sipser 5.1,5.3, 6.2) Reducibility Examples of undecidable problems Mapping reducibility Decidability of Logical Theories. Reduction techniques. For proving B is undecidable

275 views • 11 slides

Decidable languages

CSC 4170 Theory of Computation. Decidable languages. Section 4.1. 4.1.a. Decidable: {1,3,5} ? {x | x is even} {x | x is a perfect square} {x | x 2 -10x = 0} {x | x=y * z for some integers y,z>1 (i.e. x is not prime)} {x | x is a prime (i.e. x is not divisible by anything except 1 and

255 views • 7 slides

An Undecidable Language

[Section 4.2]. An Undecidable Language. A TM = { <M,w> | M is a TM that accepts string w } Turing-recognizable? Turing-decidable?. [Section 4.2]. An Undecidable Language. A bit about infinite sets and their sizes ( diagonalization ):

82 views • 7 slides

L HALT = {<M,w> | TM M halts on w}

201 views • 5 slides