Can Anything from Noether’s Theorem Be Salvaged for Discrete Dynamical Systems?

  • Silvio Capobianco
  • Tommaso Toffoli
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6714)


The dynamics of a physical system is linked to its phase-space geometry by Noether’s theorem, which holds under standard hypotheses including continuity. Does an analogous theorem hold for discrete systems? As a testbed, we take the Ising spin model with both ferromagnetic and antiferromagnetic bonds. We show that—and why—energy not only acts as a generator of the dynamics for this family of systems, but is also conserved when the dynamics is time-invariant.


analytical mechanics of cellular automata second-order dynamics energy conservation energy as generator of the dynamics Noether’s theorem in the discrete 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Silvio Capobianco
    • 1
  • Tommaso Toffoli
    • 2
  1. 1.Inst. of Cybernetics at TUTTallinnEstonia
  2. 2.ECE Dept.Boston Univ.BostonUSA

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