Atomic Gliders and CA as Language Generators (Extended Version)

Dana Fisman; Noa Izsak

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arXiv · 2511.12656

Atomic Gliders and CA as Language Generators (Extended Version)

Dana Fisman·Noa Izsak

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Abstract

Cellular automata (CA) are well-studied models of decentralized parallel computation, known for their ability to exhibit complex global behavior from simple local rules. While their dynamics have been widely explored through simulations, a formal treatment of CA as genuine language generators remains underdeveloped. We formalize CA-expressible languages as sets of finite words obtained by projecting the non-quiescent segments of configurations reachable by one-dimensional, deterministic, synchronous CA over bi-infinite grids. These languages are defined with respect to sets of initial configurations specified by a regular language as in regular model checking. To capture structured dynamics, we propose a glider-based generative semantics for CA. Inspired by the classical notion of gliders, we define a glider as a one-cell entity carrying a symbol in a certain velocity under well defined interaction semantics. We show that despite the regularity of the initial configurations and the locality of the transition rules, the resulting languages can exhibit non-regular and even non-context-free structure. This positions regular-initialized CA languages as a surprisingly rich computational model, with potential applications in the formal analysis of linearly ordered MAS.

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Dana Fisman, Noa Izsak. 2025-11-16. Atomic Gliders and CA as Language Generators (Extended Version). https://arxiv.org/abs/2511.12656

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