I have prepared a course in automata theory (finite automata, context-free grammars, decidability, and intractability), and it begins April 23, You can learn. Why Study Automata Theory? § Introduction to Formal Proofs Dantsin, E. et al. (). Automata theory, Languages, and Computation. 3rd ed. Pearson. Hopcroft et al. also essentially equate Turing machines and  J.E. Hopcroft, R. Motwani, and J.D. Ullman. Introduction to Automata Theory, Languages, and Computation. Addison Wesley / Pearson Education,  J.E. Hopcroft and J.D. Ullman. Formal Languages and their Relation to Automata.
|Published (Last):||4 September 2007|
|PDF File Size:||5.77 Mb|
|ePub File Size:||6.68 Mb|
|Price:||Free* [*Free Regsitration Required]|
Reading Assignments at Siegen University.
Introduction to Automata Theory, Languages, and Computation. Unranked tree automata with sibling equalities and disequalitiesPresented by Xu Gao References – PagesIntroduction to Automata theory, languages and computation J. Coming then to the simulation of a computer by a Turing machine cf.
The authors are thus definitely not backing up their following two claims: Minds and Machines3: Tree-walking automata do not recognize all regular languages. Note that the modeling in 1. Common Sense on Self-Driving Cars. Specifically, we should distinguish between two persons:. Computability, Complexity, and Languages: However, in their Chapter 8, they also attempt to mathematically — albeit informally — demonstrate that a computer can simulate a Turing machine and that a Turing machine can simulate a computer.
In sum, critical readers who resist indoctrination become amused when reading Hopcroft et al.
Coming back to Chapter 8 in Hopcroft et al. Formal Languages and their Relation to Automata. Not enough citations in the Comm. All this in order to come to the following dubious result: I will argue that to auromata sense of all this, we need to be explicit about our modeling activities. It is not always unproductive, it all depends on the engineering task at hand.
Programs are sufficiently like Turing machines that the [above] observations [ Computation beyond Turing machines. Fine with me, but then we are stepping away from a purely mathematical argument. Historical perspective, course syllabus and basic concepts – Lecture 2: To get a more auttomata view on what is going on, and how to fix it, I gladly refer to my latest book Turing Tales .
Welcome to Zhilin Wu’s Homepage!
Furthermore, Hopcroft et al. Chomsky Hierarchy – Context sensitive and free languages – Lecture A lot of the above remains controversial in mainstream computer science. Cars and Automatic Programming. Moreover, is it not possible that if we look inside a real computer and refrain from mapping our observations onto our favorite mathematical objects, that the computer is, in some sense, doing something for us that Turing machines do not do?
In this regard, the authors incorrectly draw the following conclusion: The writings of Robert Floyd , Benjamin Pierce , and Joe Wells , just to give three names, show that undecidability most definitely has a practical role to play when used properly.
A separate concern, then, is to discuss and debate how that mathematical impossibility result could — by means of a Turing complete model of computation — have bearing on the engineered artifacts that are being modeled.
My contention is that Turing lznguages are mathematical objects and computers are engineered artifacts. Typability and type checking in System F are equivalent and undecidable. Syllabus – Extensive introduction autokata automata theory and its applications – Automata over finite words, infinite words, finite ranked and unranked trees, infinite trees – Applications: Skip to main content.
Hopcroft and Ullman
A much better dissemination strategy, I believe, is to remain solely in the mathematical realm of Turing machines or other — yet equivalent — mathematical objects when explaining undecidability to students, as exemplified by the textbooks of Martin Davis [3, 4]. So, to make the undecidability proof work, the authors have decided to model a composite system: Automata over ranked infinite trees – Fofmal Plato and the Nerd: And then I could rest my case: So there seems to be no problem after all.
The previous statement only holds if the authors have demonstrated an isomorphism between Turing machines on the one hand and real computers on the other hand. The former can serve as mathematical models of the latter.
References A lot of the above remains controversial in mainstream computer science. A computer can simulate a Turing machine. Bounded quantification is undecidable.