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I was wondering whether there are primitive symbolic substitutions over $\mathbb{Z}^d$ and alphabet $\mathcal{A}$ whose associated subshift is equal to an aperiodic SFT. By SFT here I mean a subshift of finite type, as in this link or this thread.

This might be a simple and trivial answer to this, but I was hoping some knowledgeable person will be able to clarify some of my confusion.

My understanding is that in one dimension, this is impossible since we can find a periodic sequence in the substitution subshift. One can see this by finding a cycle in a De-Brujin graph associated to the substitution subshift. I believe that in fact any minimal subshift in one dimension should contain some periodic sequence.

It is my understanding that in $2$ dimensions, the situation is different. I know that there are minimal SFTs which are aperiodic, since we can translate Wang tiles to SFTs in $\mathcal{A}^{\mathbb{Z}^2}$. I was wondering whether there is a constant 'length' substitution, given by $S:\mathcal{A}\to \mathcal{A}^{Q}$ for $Q=\prod_{j=1}^d\{ 0,1,...,m_{j}-1 \}$, such that its susbtitution subshift is an aperiodic SFT? I know of a paper by Sébastien Labbé that gives Wang tiles generated from a substitution, but I am unsure whether the Wang shift is a factor of the substitution subshift. It also does not seem clear to me, whether one can translate this result to a constant length subshift.

I've confused myself over this for some weeks now, and was wondering whether perhaps some knowledgeable source could help clarify this. I would appreciate any clarification on this subject and any new information on this topic.

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  • $\begingroup$ can you expand the SFT acronym? $\endgroup$
    – kodlu
    Commented Aug 10, 2023 at 14:04
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    $\begingroup$ @kodlu I've added two links in an edit to hopefully clarify what I mean. $\endgroup$ Commented Aug 10, 2023 at 14:24
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    $\begingroup$ lacl.fr/pvanier/rech/cirm.pdf I think you are looking for intrinsically substitutive tile sets $\endgroup$
    – Ville Salo
    Commented Aug 10, 2023 at 14:38
  • $\begingroup$ If I'm not mistaken, the Goodman-Strauss Annals paper proves that any block substitution is MLD to an SFT? $\endgroup$
    – Dan Rust
    Commented Aug 10, 2023 at 19:54
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    $\begingroup$ "Are the alphabet of the substitution essentially a triple corresponding to each layer?" that is my understanding. I haven't read this in detail. It's not the only known construction anyway. $\endgroup$
    – Ville Salo
    Commented Aug 11, 2023 at 10:08

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