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Generic smooth maps are not robustly Turing‑universal

Prove that for any compact computable manifold M, a C^∞ generic diffeomorphism f: M → M cannot be extended to a robustly Turing‑universal computational dynamical system (CDS) with any choice of encoder, decoder, and slowdown function.

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Background

The paper establishes strong obstructions to robust Turing universality for broad classes of smooth dynamical systems, including Axiom A systems and measure‑preserving (integrable) systems. Motivated by these results and expectations from differentiable dynamics, the authors propose a conjecture asserting a generic non‑universality statement for smooth diffeomorphisms.

They also note partial progress: under a strong condition on the decoder and a constant slowdown, they prove a non‑universality result (Theorem 4.3), and suggest that Palis’ conjectures might help resolve the general case. The conjecture seeks a definitive, unconditional generic non‑universality statement.

References

We venture the following conjecture: A C\infty generic f: M \to M cannot be extended to a robustly Turing-universal CDS.

Computational Dynamical Systems (2409.12179 - Cotler et al., 18 Sep 2024) in Conjectures about generic diffeomorphisms, Section 4.2