Quantum features of natural cellular automata

TL;DR

This paper explores how natural cellular automata with integer variables can mimic quantum mechanics, including superposition, interference, and entanglement, and can be mapped to continuum models via Sampling Theory.

Contribution

It introduces a class of Hamiltonian cellular automata based on integer variables, demonstrating their ability to reproduce quantum features and form multipartite systems consistent with quantum tensor structures.

Findings

Automata exhibit quantum-like linear evolution and conservation laws.

They can be mapped to continuum models using Sampling Theory.

Multipartite automata can produce quantum interference and entanglement.

Abstract

Cellular automata can show well known features of quantum mechanics, such as a linear rule according to which they evolve and which resembles a discretized version of the Schroedinger equation. This includes corresponding conservation laws. The class of "natural" Hamiltonian cellular automata is based exclusively on integer-valued variables and couplings and their dynamics derives from an Action Principle. They can be mapped reversibly to continuum models by applying Sampling Theory. Thus, "deformed" quantum mechanical models with a finite discreteness scale $l$ are obtained, which for $l\rightarrow 0$ reproduce familiar continuum results. We have recently demonstrated that such automata can form "multipartite" systems consistently with the tensor product structures of nonrelativistic many-body quantum mechanics, while interacting and maintaining the linear evolution. Consequently, the Superposition Principle fully applies for such primitive discrete deterministic automata and their composites and can produce the essential quantum effects of interference and entanglement.