Cellular Automata Theory

Total Page:16

File Type:pdf, Size:1020Kb

Cellular Automata Theory Cellular Automaton Supercollider: an abstract model Genaro Juárez Martínez [email protected] http://uncomp.uwe.ac.uk/genaro/ International Center of Unconventional Computing, University of the West of England, United Kingdom http://uncomp.uwe.ac.uk/ Laboratorio de Ciencias de la Computación, Universidad Nacional Autónoma de México, México http://uncomp.uwe.ac.uk/LCCOMP/ Centre for Chaos and Complex Networks, City University of Hong Kong, Hong Kong, P. R. China http://www.ee.cityu.edu.hk/~cccs/ Foundation of Computer Science Laboratory, Hiroshima University, Hiroshima, Japan http://www.iec.hiroshima-u.ac.jp/ Laboratoire de Recherche Scientifique, Paris, France http://labores.eu/ Department of Electronic Engineering, City University of Hong Kong Hong Kong SAR, P. R. China, April 2, 2012 School of Science, Hangzhou Dianzi University Hanhzhou, Zhejiang, P. R. China, April 11, 2012 Cellular Automata Theory Cellular automata (CA) are very simple mathematical functions that evolve massively in parallel on 1, 2, 3, 4, ..., n, dimensions in a regular lattice. Invented by John von Neumann in 1956 and popularized amply by John Horton Conway and his famous additive-binary 2d CA The Game of Life in 1970. So, in 1986 Stephen Wolfram has been introduced the 1D CA and its famous “classes” where CA may fall. class I. Homogenous class II. Periodic class III. Chaos class IV. Complexity This classification is extended to any dynamical systems in general. the unpredictable ... Simplicity in CA are famous representing “patterns”, evolving as: complex dynamics, chaotic systems, and trivial behaviour. All they captured from random initial conditions generally. In this way, kaleidoscope is a funny example related of this problem. ! How many configurations there are? ! How long shall be the evolution to repeat the configuration? ! Is here impossible to predict the behaviour in each evolution Could you write an algorithm to calculate the set of configurations or determines the evolution? Sir David Brewster (Scot. Brit.), the physicist who invented de kaleidoscope in 1816 Hulton-Deutsch Collection/Corbis Encyclopaedia Britannica A kaleidoscope patterns Mark Gibson-Corbis Encyclopaedia Britannica Cellular Automata Cellular automata (CA) are discrete dynamical systems evolving on an infinite regular lattice. A CA is a 4-tuple A = <!, µ, ", c0> evolving in d-dimensional lattice, where d ! Z+. Such that: • ! represents the finite alphabet • µ is the local connection, where, µ = {x0,1,...,n-1:d | x ! !}, therefore, µ is a neighbourhood • " is the local function, such that, " : !µ " ! Z • c0 is the initial condition, such that, c0 ! ! Also, the local function induces a global transition between configurations: Z Z #" : ! " ! . CA dynamics in one dimension Elemental CA (ECA) is defined as follows: • ! = {0,1} • µ = (x+1,x0,x-1) such that x ! ! • " : !3 " ! • µ = {c0 | x ! !} the initial condition is the first ring with t = 0 History in ECA Rule 110 Stephen Wolfram, 1959-? Stephen Wolfram (1994) Cellular Automata and Complexity: collected papers, Addison-Wesley Publishing Company. Stephen Wolfram (2002) A New Kind of Science, Wolfram Media, Inc., Champaign, Illinois. History (literature) in Rule 110 In November 1998 at the Santa Fe Institute Matthew Cook had demonstrates that Rule 110 is Universal! Simulating a novel cyclic tag system. Wentian Li & Mats G. Nordahl (1992) "Transient behavior of cellular automaton rule 110," Physics Letters A 166, 335-339. Stephen Wolfram (1994) Cellular Automata and Complexity: collected papers, Addison-Wesley Publishing Company. Matthew Cook (1999) “Introduction to the activity of rule 110,” (copyright 1994-1998 Matthew Cook), http:// w3.datanet.hu/~cook/Workshop/CellAut/Elementary/Rule110/110pics.html Harold V. McIntosh (1999) “Rule 110 as it relates to the presence of gliders,” http://delta.cs.cinvestav.mx/~mcintosh/oldweb/pautomata.html Genaro J. Martínez & Harold V. McIntosh (2001) "ATLAS: Collisions of gliders like phases of ether in Rule 110," http://uncomp.uwe.ac.uk/genaro/Papers/Papers_on_CA.html Stephen Wolfram (2002) A New Kind of Science, Wolfram Media, Inc., Champaign, Illinois. Harold V. McIntosh (2002) “Rule 110 Is Universal!” http://delta.cs.cinvestav.mx/~mcintosh/oldweb/pautomata.html Genaro J. Martínez, Harold V. McIntosh & Juan C. Seck Tuoh Mora (2003) "Production of gliders by collisions in Rule 110," Lecture Notes in Computer Science 2801, 175-182. Matthew Cook (2004) “Universality in Elementary Cellular Automata,” Complex Systems 15(1), 1-40. History (literature) in Rule 110 Turlough Neary & Damien Woods (2006) "P-completeness of cellular automaton Rule 110," Lecture Notes in Computer Science 4051, 132-143. Genaro J. Martínez, Harold V. McIntosh & Juan C. Seck Tuoh Mora (2006) "Gliders in Rule 110," International Journal of Unconventional Computing 2(1), 1-49. Genaro J. Martínez, Harold V. McIntosh, Juan C. Seck Tuoh Mora, & Sergio V. Chapa Vergara (2007) "Rule 110 objects and other constructions based-collisions," Journal of Cellular Automata 2(3), 219-242. Matthew Cook (2008) "A Concrete View of Rule 110 Computation," In The Complexity of Simple Programs, T. Neary, D. Woods, A. K. Seda, & N. Murphy (Eds.), 31-55. Genaro J. Martínez, Harold V. McIntosh, Juan C. Seck Tuoh Mora, & Sergio V. Chapa Vergara (2008) "Determining a regular language by glider-based structures called phases fi_1 in Rule 110," Journal of Cellular Automata 3(3), 231-270. José M. Sausedo-Solorio (2010) Conservation features in binary collisions for rule 110 cellular automaton, International Journal of Modern Physics C 21(7), 931-942. Genaro J. Martínez, Harold V. McIntosh, Juan C. Seck-Tuoh-Mora, & Sergio V. Chapa-Vergara (2011) "Reproducing the cyclic tag system developed by Matthew Cook with Rule 110 using the phases f1_1," Journal of Cellular Automata 6(2-3), 121-161. Genaro J. Martínez, Andrew Adamatzky, Christopher R. Stephens, Alejandro F. Hoeflich (2011) "Cellular automaton supercolliders," International Journal of Modern Physics C 22(4), 419-439. Fangyue Chen, Weifeng Jin, Guangrong Chen, & Lin Chen (2012) "Chaos emerged on the “edge of chaos”," International Journal of Computer Mathematics, by publish. "Rule 110 repository" http://uncomp.uwe.ac.uk/genaro/Rule110.html Dynamics in Rule 110 Rule 110 is an elemental cellular automaton. The local function determining the behaviour is: Random evolution in Rule 110. Initial density 50% with a ring of 539 cells for 568 generations. Set of particles in Rule 110 Formal languages and particles as strings The formal languages theory provides a way to study sets of chains from a finite alphabet. The languages can be seen as inputs for some classes of machines or as the final result from a typesetter substitution system i.e., a generative grammar into the Chomsky's classification. Lyman P. Hurd (1987) "Formal Language Characterizations of Cellular Automaton Limit Sets," Complex Systems 1, 69-80. Stephen Wolfram (1984) "Computation Theory on Cellular Automata," Communication in Mathematical Physics 96, 15-57. John E. Hopcroft & Jeffrey D. Ullman (1987) Introduction to Automata Theory Languajes, and Computation, Addison-Wesley Publishing Company. Collaborative Research Center SFB 676, "Particles, Strings, and the Early Feynman diagram Universe", Universität Hamburg , http://wwwiexp.desy.de/sfb676/ Particles as strings in CA: the de Bruijn diagram For an one-dimensional cellular automaton of order (k,r), the de Bruijn diagram is defined as a directed graph with k2r vertices and k2r+1 edges. The vertices are labeled with the elements of the alphabet of length 2r. An edge is directed from vertex i to vertex j, if and only if, the 2r-1 final symbols of i are the same that the 2r-1 initial ones in j forming a neighbourhood of 2r+1 states represented by i # j. In this case, the edge connecting i to j is labeled with "(i # j). The connection matrix M corresponding with the de Bruijn diagram is as follows: Harold V. McIntosh (1991) "Linear cellular automata via de Bruijn diagrams," http://delta.cs.cinvestav.mx/~mcintosh/ oldweb/pautomata.html Harold V. McIntosh (2009) One Dimensional Cellular Automata, Luniver Press. Burton H. Voorhees (1996) Computational analysis of one-dimensional cellular automata, World Scientific Series on Nonlinear Science, Series A, Vol. 15. Particles as strings in CA: the de Bruijn diagram Paths in the de Bruijn diagram may represent chains, configurations or classes of configurations in the evolution space. Now we must discuss another variant where the de Bruijn diagram can be extended to determine greater sequences by the period and the shift of their cells in the evolution space in Rule 110. A problem is that the calculation of extended de Bruijn diagrams grows exponentially with order k2rn $ n ! Z+. de Bruijn diagram for Rule 110 Particles as strings in CA: attractors class IV: very long transients, very long periodic attractors low in-degree, low leaf density (complex dynamics). Particles as strings in Rule 110 Regular language in Rule 110 (2001-2004) particle A [111110] = A(f1_1), 6 cells, 1l-0r [11111000111000100110] = A(f2_1), 20 cells, 2l-3r [11111000100110100110] = A(f3_1), 20 cells, 3l-2r A(f4_1) = A(f1_1) particle B [11111010] = B(f1_1), 8 cells, 1l-1r [11111000] = B(f2_1), 8 cells, 2l-0r [1111100010011000100110] = B(f3_1), 22 cells, 3l-3r [11100110] = B(f4_1), 8 cells, 0l-2r ... Doug Lind, “Structures in rule 110,” In Cellular Automata and Complexity: Collected Papers, Stephen Wolfram, Table of Properties, page 577, http://www.stephenwolfram.com/publications/articles/ca/86-caappendix/16/text.html Genaro J. Martínez, Harold V. McIntosh, Juan C. Seck Tuoh Mora, & Sergio V. Chapa Vergara (2008) "Determining a regular language by glider-based structures called phases fi_1 in Rule 110," Journal of Cellular Automata 3(3), 231-270. "Regular language in Rule 110" (2004) http://uncomp.uwe.ac.uk/genaro/rule110/listPhasesR110.txt Collisions in Rule 110 producing a producing a producing a particle generator gap of 28 cells meta particle Genaro J. Martínez & Harold V. McIntosh (2001) "ATLAS: Collisions of gliders like phases of ether in Rule 110," http:// uncomp.uwe.ac.uk/genaro/Papers/Papers_on_CA.html Genaro J.
Recommended publications
  • Impartial Games Emulating One-Dimensional Cellular Automata and Undecidability
    Impartial games emulating one-dimensional cellular automata and undecidability Urban Larsson Department of Mathematical Sciences Chalmers University of Technology and G¨oteborg University April 18, 2021 Abstract We study two-player take-away games whose outcomes emulate two-state one-dimensional cellular automata, such as Wolfram's rules 60 and 110. Given an initial string consisting of a central data pattern and periodic left and right patterns, the rule 110 cellular automaton was recently proved Turing-complete by Matthew Cook. Hence, many questions regarding its behavior are algorithmically undecidable. We show that similar questions are undecidable for our rule 110 game. 1 Introduction We study the inter-connections between two popular areas of mathematics, two-player combinatorial games e.g. [BCG04] and cellular automata (CAs) [N66, HU79, W84a, W84b, W84c, W86, W02]. We present an infinite class of games and prove that their outcomes (or winning strategies) emulate corre- arXiv:1201.1039v1 [math.CO] 5 Jan 2012 sponding one-dimensional CAs. In particular we study some recent results of Matthew Cook, [C04, C08], concerning algorithmic undecidability of Stephen Wolfram's well known elementary cellular automaton, rule 110, and interpret these results in the setting of our games. The universality of the rule 110 automaton was conjectured by S. Wolfram in 1985. It is also discussed in the remarkable book, [W02]. Our games are played between two players and are purely combinatorial| there is no element of chance and no hidden information. They are similar 1 to the take away games found in [G66, S70, Z96]. In such games the players take turns in removing tokens (coins, matches, stones) from a finite number of heaps, each with a given finite number of tokens.
    [Show full text]
  • Language and Automata Theory and Applications
    LANGUAGE AND AUTOMATA THEORY AND APPLICATIONS Carlos Martín-Vide Characterization • It deals with the description of properties of sequences of symbols • Such an abstract characterization explains the interdisciplinary flavour of the field • The theory grew with the need of formalizing and describing the processes linked with the use of computers and communication devices, but its origins are within mathematical logic and linguistics A bit of history • Early roots in the work of logicians at the beginning of the XXth century: Emil Post, Alonzo Church, Alan Turing Developments motivated by the search for the foundations of the notion of proof in mathematics (Hilbert) • After the II World War: Claude Shannon, Stephen Kleene, John von Neumann Development of computers and telecommunications Interest in exploring the functions of the human brain • Late 50s XXth century: Noam Chomsky Formal methods to describe natural languages • Last decades Molecular biology considers the sequences of molecules formed by genomes as sequences of symbols on the alphabet of basic elements Interest in describing properties like repetitions of occurrences or similarity between sequences Chomsky hierarchy of languages • Finite-state or regular • Context-free • Context-sensitive • Recursively enumerable REG ⊂ CF ⊂ CS ⊂ RE Finite automata: origins • Warren McCulloch & Walter Pitts. A logical calculus of the ideas immanent in nervous activity. Bulletin of Mathematical Biophysics, 5:115-133, 1943 • Stephen C. Kleene. Representation of events in nerve nets and
    [Show full text]
  • 2020 SIGACT REPORT SIGACT EC – Eric Allender, Shuchi Chawla, Nicole Immorlica, Samir Khuller (Chair), Bobby Kleinberg September 14Th, 2020
    2020 SIGACT REPORT SIGACT EC – Eric Allender, Shuchi Chawla, Nicole Immorlica, Samir Khuller (chair), Bobby Kleinberg September 14th, 2020 SIGACT Mission Statement: The primary mission of ACM SIGACT (Association for Computing Machinery Special Interest Group on Algorithms and Computation Theory) is to foster and promote the discovery and dissemination of high quality research in the domain of theoretical computer science. The field of theoretical computer science is the rigorous study of all computational phenomena - natural, artificial or man-made. This includes the diverse areas of algorithms, data structures, complexity theory, distributed computation, parallel computation, VLSI, machine learning, computational biology, computational geometry, information theory, cryptography, quantum computation, computational number theory and algebra, program semantics and verification, automata theory, and the study of randomness. Work in this field is often distinguished by its emphasis on mathematical technique and rigor. 1. Awards ▪ 2020 Gödel Prize: This was awarded to Robin A. Moser and Gábor Tardos for their paper “A constructive proof of the general Lovász Local Lemma”, Journal of the ACM, Vol 57 (2), 2010. The Lovász Local Lemma (LLL) is a fundamental tool of the probabilistic method. It enables one to show the existence of certain objects even though they occur with exponentially small probability. The original proof was not algorithmic, and subsequent algorithmic versions had significant losses in parameters. This paper provides a simple, powerful algorithmic paradigm that converts almost all known applications of the LLL into randomized algorithms matching the bounds of the existence proof. The paper further gives a derandomized algorithm, a parallel algorithm, and an extension to the “lopsided” LLL.
    [Show full text]
  • Cellular Automata and Agent-Based Models
    Cellular automata and agent-based models Matthew Macauley Department of Mathematical Sciences Clemson University http://www.math.clemson.edu/~macaule/ Math 4500, Spring 2016 M. Macauley (Clemson) Cellular automata and agent-based models Math 4500, Spring 2016 1 / 18 Cellular automata A cellular automaton (CA) consists of a regular grid of cells, each one being ON (1) or OFF (0). At each time-step, every state is updated based on the states of its neighbors. As a simple example, consider an infinite 1D grid of cells, each one having the following update rule, called \Rule 30": The following shows the evolution of the dynamics over t 0; 1;:::; 8, starting with a single \ON" cell: M. Macauley (Clemson) Cellular automata and agent-based models Math 4500, Spring 2016 2 / 18 Cellular automata When you zoom out to see 200 time-steps, patterns start to emerge. A common theme with CA are that complex dynamics can emerge from simple, local interactions. M. Macauley (Clemson) Cellular automata and agent-based models Math 4500, Spring 2016 3 / 18 Cellular automata and self-organizing systems Complexity is observed all throughout the natural world, expecially in biology. Question: Can complex bevavior emerge naturally from a few simple rules? YES! For example, here is Rule 30 with a different initial condition: Many believe that CAs are key to understanding how simple rules can produce complex structures and behavior. M. Macauley (Clemson) Cellular automata and agent-based models Math 4500, Spring 2016 4 / 18 Some history Cellular automata (CA) were invented by Stanislaw Ulam and John von Neumann in the 1940s at Los Alamos National Laboratory, based on work by Alan Turing.
    [Show full text]
  • COMPUTER MODELS and AUTOMATA THEORY in BIOLOGY and MEDICINE Ion C
    Mathematical Modelling, Vol. 7, pp. 1513-1577,1986 Printed in the U,S.A. All rights reserved. Copyright C 1986 Pergamon Journals Ltd. REVIEW ARTICLE COMPUTER MODELS AND AUTOMATA THEORY IN BIOLOGY AND MEDICINE Ion C. Baianu University of Ulinois at Urbana Physical Chemistry and NMR Laboratories 567 Bevier Hall, 905 S. Goodwin Ave .Urbana, UIinois 61801 (Received 27 February 1985; revised 12 September 1985) 1. INTRODUCTION The applications of computers to biological and biomedical problem solving goes back to the very beginnings of computer science, automata theory [1], and mathematical biology [2]. With the advent of more versatile and powerful computers, biological and biomedical applications of computers have proliferated so rapidly that it would be virtually impossible to compile a comprehensive review of all developments in this field. Limitations of computer simulations in biology have also come under close scrutiny, and claims have been made that biological systems have limited information processing power [3]. Such general conjectures do not, however, deter biologists and biomedical researchers from developing new computer applications in biology and medicine. Microprocessors are being widely employed in biological laboratories both for automatic data acquisition/processing and modeling; one particular area, which is of great biomedical interest, involves fast digital image processing and is already established for routine clinical examinations in radiological and nuclear medicine centers, Powerful techniques for biological research are routinely employing dedicated, on-line microprocessors or array processors; among such techniques are: Fourier-transform nuclear magnetic resonance (NMR), NMR imaging (or tomography), x-ray tomography, x-ray diffraction, high performance liquid chromatography, differential scanning calorimetry and mass spectrometry.
    [Show full text]
  • A Mathematical Theory of Computation?
    A Mathematical Theory of Computation? Simone Martini Dipartimento di Informatica { Scienza e Ingegneria Alma mater studiorum • Universit`adi Bologna and INRIA FoCUS { Sophia / Bologna Lille, February 1, 2017 1 / 57 Reflect and trace the interaction of mathematical logic and programming (languages), identifying some of the driving forces of this process. Previous episodes: Types HaPOC 2015, Pisa: from 1955 to 1970 (circa) Cie 2016, Paris: from 1965 to 1975 (circa) 2 / 57 Why types? Modern programming languages: control flow specification: small fraction abstraction mechanisms to model application domains. • Types are a crucial building block of these abstractions • And they are a mathematical logic concept, aren't they? 3 / 57 Why types? Modern programming languages: control flow specification: small fraction abstraction mechanisms to model application domains. • Types are a crucial building block of these abstractions • And they are a mathematical logic concept, aren't they? 4 / 57 We today conflate: Types as an implementation (representation) issue Types as an abstraction mechanism Types as a classification mechanism (from mathematical logic) 5 / 57 The quest for a \Mathematical Theory of Computation" How does mathematical logic fit into this theory? And for what purposes? 6 / 57 The quest for a \Mathematical Theory of Computation" How does mathematical logic fit into this theory? And for what purposes? 7 / 57 Prehistory 1947 8 / 57 Goldstine and von Neumann [. ] coding [. ] has to be viewed as a logical problem and one that represents a new branch of formal logics. Hermann Goldstine and John von Neumann Planning and Coding of problems for an Electronic Computing Instrument Report on the mathematical and logical aspects of an electronic computing instrument, Part II, Volume 1-3, April 1947.
    [Show full text]
  • Universality in Elementary Cellular Automata
    Universality in Elementary Cellular Automata Matthew Cook Department of Computation and Neural Systems,! Caltech, Mail Stop 136-93, Pasadena, California 91125, USA The purpose of this paper is to prove a conjecture made by Stephen Wolfram in 1985, that an elementary one dimensional cellular automaton known as “Rule 110” is capable of universal computation. I developed this proof of his conjecture while assisting Stephen Wolfram on research for A New Kind of Science [1]. 1. Overview The purpose of this paper is to prove that one of the simplest one di- mensional cellular automata is computationally universal, implying that many questions concerning its behavior, such as whether a particular se- quence of bits will occur, or whether the behavior will become periodic, are formally undecidable. The cellular automaton we will prove this for is known as “Rule 110” according to Wolfram’s numbering scheme [2]. Being a one dimensional cellular automaton, it consists of an infinitely long row of cells "Ci # i $ !%. Each cell is in one of the two states "0, 1%, and at each discrete time step every cell synchronously updates ' itself according to the value of itself and its nearest neighbors: &i, Ci ( F(Ci)1, Ci, Ci*1), where F is the following function: F(0, 0, 0) ( 0 F(0, 0, 1) ( 1 F(0, 1, 0) ( 1 F(0, 1, 1) ( 1 F(1, 0, 0) ( 0 F(1, 0, 1) ( 1 F(1, 1, 0) ( 1 F(1, 1, 1) ( 0 This F encodes the idea that a cell in state 0 should change to state 1 exactly when the cell to its right is in state 1, and that a cell in state 1 should change to state 0 just when the cells on both sides are in state 1.
    [Show full text]
  • Introduction to Theory of Computation
    Introduction to Theory of Computation Anil Maheshwari Michiel Smid School of Computer Science Carleton University Ottawa Canada anil,michiel @scs.carleton.ca { } April 17, 2019 ii Contents Contents Preface vi 1 Introduction 1 1.1 Purposeandmotivation ..................... 1 1.1.1 Complexitytheory .................... 2 1.1.2 Computability theory . 2 1.1.3 Automatatheory ..................... 3 1.1.4 Thiscourse ........................ 3 1.2 Mathematical preliminaries . 4 1.3 Prooftechniques ......................... 7 1.3.1 Directproofs ....................... 8 1.3.2 Constructiveproofs. 9 1.3.3 Nonconstructiveproofs . 10 1.3.4 Proofsbycontradiction. 11 1.3.5 The pigeon hole principle . 12 1.3.6 Proofsbyinduction. 13 1.3.7 Moreexamplesofproofs . 15 Exercises................................. 18 2 Finite Automata and Regular Languages 21 2.1 An example: Controling a toll gate . 21 2.2 Deterministic finite automata . 23 2.2.1 Afirstexampleofafiniteautomaton . 26 2.2.2 Asecondexampleofafiniteautomaton . 28 2.2.3 A third example of a finite automaton . 29 2.3 Regularoperations ........................ 31 2.4 Nondeterministic finite automata . 35 2.4.1 Afirstexample ...................... 35 iv Contents 2.4.2 Asecondexample..................... 37 2.4.3 Athirdexample...................... 38 2.4.4 Definition of nondeterministic finite automaton . 39 2.5 EquivalenceofDFAsandNFAs . 41 2.5.1 Anexample ........................ 44 2.6 Closureundertheregularoperations . 48 2.7 Regularexpressions. .. .. 52 2.8 Equivalence of regular expressions and regular languages . 56 2.8.1 Every regular expression describes a regular language . 57 2.8.2 Converting a DFA to a regular expression . 60 2.9 The pumping lemma and nonregular languages . 67 2.9.1 Applications of the pumping lemma . 69 2.10Higman’sTheorem ........................ 76 2.10.1 Dickson’sTheorem .
    [Show full text]
  • A Combinatorial Approach to the Theory of O~-Automata
    INFORMATION AND CONTROL 48, 261-283 (1981) A Combinatorial Approach to the Theory of o~-Automata WOLFGANG THOMAS Mathematisches Institut der Universitdt, 7800 Freiburg, West Germany A combinatorial lemma is proved and used here to derive new results on ~o- automata and to give simpler proofs of known ones. In particular, we reprove McNaughton's fundamental theorem (characterizing the o~-regular sequence-sets), without having to construct a sophisticated w-automaton. The theorem is obtained by coding the behaviour of automata in a second-order language and a simple application of the lemma. In close analogy (now referring to a first-order language) a theory of counter-free co-automata is developed; it is shown that these automata are appropriate for characterizing the co-star-free sequence-sets. Finally, the lemma is applied in mathematical logic: Here new normal form theorems and also decidability results are proved for the first-order and the monadic second-order theory of certain structures over the ordering of natural numbers. 0. INTRODUCTION A central result in the theory of finite automata accepting co-sequences (short: co-automata) is the theorem of McNaughton (1966). It characterizes the sequence-sets accepted by co-automata as the co-regular sequence-sets. McNaughton's proof involves an intricate construction of an co-automaton; it shows "how a bounded memory (finite automaton) can be made to keep track of essential information, accruing in an ever growing past" (B/ichi (1977)). Modified and improved presentations of this construction have since been given in Rabin (1972), B/ichi (1973), Choueka (1974) and Trakhtenbrot and Barzdin (1973).
    [Show full text]
  • Combinatorics, Automata and Number Theory
    Combinatorics, Automata and Number Theory CANT Edited by Val´erie Berth´e LIRMM - Univ. Montpelier II - CNRS UMR 5506 161 rue Ada, 34392 Montpellier Cedex 5, France Michel Rigo Universit´edeLi`ege, Institut de Math´ematiques Grande Traverse 12 (B 37), B-4000 Li`ege, Belgium 2 Number representation and finite automata Christiane Frougny Univ. Paris 8 and LIAFA, Univ. Paris 7 - CNRS UMR 7089 Case 7014, F-75205 Paris Cedex 13, France Jacques Sakarovitch LTCI, CNRS/ENST - UMR 5141 46, rue Barrault, F-75634 Paris Cedex 13, France. Contents 2.1 Introduction 5 2.2 Representation in integer base 8 2.2.1 Representation of integers 8 2.2.2 The evaluator and the converters 11 2.2.3 Representation of reals 18 2.2.4 Base changing 23 2.3 Representation in real base 23 2.3.1 Symbolic dynamical systems 24 2.3.2 Real base 27 2.3.3 U-systems 35 2.3.4 Base changing 43 2.4 Canonical numeration systems 48 2.4.1 Canonical numeration systems in algebraic number fields 48 2.4.2 Normalisation in canonical numeration systems 50 2.4.3 Bases for canonical numeration systems 52 2.4.4 Shift radix systems 53 2.5 Representation in rational base 55 2.5.1 Representation of integers 55 2.5.2 Representation of the reals 61 2.6 A primer on finite automata and transducers 66 2.6.1 Automata 66 2.6.2 Transducers 68 2.6.3 Synchronous transducers and relations 69 2.6.4 The left-right duality 71 3 4 Ch.
    [Show full text]
  • A Theory of Regular Queries
    A Theory of Regular Queries Moshe Y. Vardi Rice University [email protected] ABSTRACT [22], he proposed using first-order logic as a declarative database A major theme in relational database theory is navigat- query language [23]. This led to the development of both ing the tradeoff between expressiveness and tractability for SEQUEL [16] and QUEL [54], as practical relational query query languages, where the query-containment problem is languages realizing Codd's idea, ultimately giving in 1986 considered a benchmark of tractability. The query class rise to the SQL standard [27], which has continued to evolve UCQ, consisting off unions of conjunctive queries, is a frag- over the past 30 years. ment of first-order logic that has a decidable query contain- Starting in the late 1970s, Codd's definition of first-order ment problem, but its expressiveness is limited. Extend- logic as \expressively complete" came under serious criti- ing UCQ with recursion yields Datalog, an expressive query cism [4], and various proposals emerged on how to extend language that has been studied extensively and has recently its expressive power [4, 6, 17], whose essence was to extend become popular in application areas such as declarative net- first-order logic with recursion, which was added to SQL in working. Unfortunately, Datalog has an undecidable query 1999 by way of common table expressions [29]. On the re- containment problem. Identifying a fragment of Datalog search side, the most popular relational language embodying that is expressive enough for applications but has a decid- recursion is Datalog [15], describe in more details below.
    [Show full text]
  • Arxiv:2001.09864V2 [Cs.FL]
    Provenance for Regular Path Queries G¨osta Grahne1 and Alex Thomo2 1 Concordia University, Montreal, Canada, [email protected] 2 University of Victoria, Victoria, Canada, [email protected] 1 Introduction It has been recognized that the result of a database query should be annotated with provenance, i.e. information about how, why, where, with what level of cer- tainty or security clearance, etc a particular fact of the query was derived. The seminal paper by Green, Tannen and Karvounarakis [4] convincingly showed that all major forms of provenance can be uniformly captured within the algebraic framework of semirings. Green et al. show that a suitably semiring-annotated positive (negation-free) relational algebra and datalog can capture the prove- nance of query results. Furthermore, the various data base semirings form a par- tial order where coarser (”smaller”) semirings can be obtained as homomorphic images of semirings with a finer grain of information. Green et al. also show that the annotated positive relational algebra and datalog form congruences within their semiring hierarchy. Regular path queries (RPQs) is the ubiquitous mechanism for querying graph databases [1]. RPQs are in essence regular expressions over the edge symbols. The answer to an RPQ on a given graph database is the set of pairs of objects (a,b), which are connected by paths spelling words in the language of the regular path query An annotated pair in the answer would naturally contain the set of words that spell paths between a and b. However, a finer grain of provenance can be obtained by annotating the words with the intermediate vertices of each path spelling the word.
    [Show full text]