Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-28T09:39:29.739Z Has data issue: false hasContentIssue false
  • English
  • Français

A new algebraic invariant for weak equivalence of sofic subshifts

Published online by Cambridge University Press:  03 June 2008

Laura Chaubard  and
Alfredo Costa
Laura Chaubard
Affiliation:
LIAFA, Université Paris VII and CNRS, Case 7014, 2 Place Jussieu, 75251 Paris Cedex 05, France; Laura.Chaubard@liafa.jussieu.fr
Alfredo Costa
Affiliation:
CMUC, Department of Mathematics, University of Coimbra, 3001-454 Coimbra, Portugal; amgc@mat.uc.pt
Get access

Abstract

It is studied how taking the inverse image by a sliding block code affects the syntactic semigroup of a sofic subshift. The main tool are ζ-semigroups, considered as recognition structures for sofic subshifts. A new algebraic invariant is obtained for weak equivalence of sofic subshifts, by determining which classes of sofic subshifts naturally defined by pseudovarieties of finite semigroups are closed under weak equivalence. Among such classes are the classes of almost finite type subshifts and aperiodic subshifts. The algebraic invariant is compared with other robust conjugacy invariants.

Keywords

Sofic subshiftconjugacyweak equivalenceζ-semigrouppseudovariety.
Type
Research Article
Information
RAIRO - Theoretical Informatics and Applications , Volume 42 , Issue 3: JM'06 , July 2008 , pp. 481 - 502
Copyright
© EDP Sciences, 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

J. Almeida, Finite semigroups and universal algebra, World Scientific, Singapore (1995), English translation.
Béal, M.-P., Fiorenzi, F., and Perrin, D., A hierarchy of shift equivalent sofic shifts. Theoret. Comput. Sci. 345 (2005) 190–205. CrossRef
M.-P. Béal, F. Fiorenzi, and D. Perrin, The syntactic graph of a sofic shift is invariant under shift equivalence. Int. J. Algebra Comput. 16 (2006), 443–460.
Béal, M.-P. and Perrin, D., A weak equivalence between shifts of finite type. Adv. Appl. Math. 29 (2002) 2, 162–171. CrossRef
D. Beauquier, Minimal automaton for a factorial transitive rational language. Theoret. Comput. Sci. 67 (1985), 65–73.
F. Blanchard and G. Hansel, Systèmes codés. Theoret. Comput. Sci. 44 (1986), 17–49.
M. Boyle and W. Krieger, Almost markov and shift equivalent sofic systems, Proceedings of Maryland Special Year in Dynamics 1986–87 (J.C. Alexander, ed.). Lect. Notes Math. 1342 (1988), pp. 33–93.
M.-P. Béal, Codage symbolique, Masson (1993).
O. Carton, Wreath product and infinite words. J. Pure Appl. Algebra 153 (2000), 129–150.
L. Chaubard, L`équivalence faible des systèmes sofiques, Master's thesis, LIAFA, Université Paris VII, July 2003, Rapport de stage de DEA.
A. Costa, Pseudovarieties defining classes of sofic subshifts closed under taking shift equivalent subshifts. J. Pure Appl. Algebra 209 (2007), 517–530.
S. Eilenberg, Automata, languages and machines, vol. B, Academic Press, New York, 1976.
R. Fischer, Sofic systems and graphs. Monatsh. Math. 80 (1975), 179–186.
G. A. Hedlund, Endomorphims and automorphisms of the shift dynamical system. Math. Syst. Theor. 3 (1969), 320–375.
W. Krieger, On sofic systems. i. Israel J. Math. 48 (1984), 305–330.
D. Lind and B. Marcus, An introduction to symbolic dynamics and coding, Cambridge University Press, Cambridge (1996).
M. Nasu, Topological conjugacy for sofic systems. Ergod. Theory Dyn. Syst. 6 (1986), 265–280.
D. Perrin and J.-E. Pin, Infinite words, Pure and Applied Mathematics, No. 141, Elsevier, London, 2004.
J.-E. Pin, Varieties of formal languages, Plenum, London (1986), English translation.
J.-E. Pin, Syntactic semigroups, Handbook of Language Theory (G. Rozenberg and A. Salomaa, eds.), Springer (1997).