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Let $M$ be a compact manifold and let $\mathrm{Diff}^{1}(M)$ denote the group of $C^{1}$-diffeomorphisms of $M$. Let $Z(f) := \{g \in \mathrm{Diff}^{1}(M) \mid gf = fg \}$ denote the centralizer of $f$. Note that the cyclic subgroup $\langle f \rangle$ generated by $f$ is always in $Z(f)$. If $Z(f) = \langle f \rangle$, then we say that $f$ has trivial centralizer. Bonatti-Crovisier-Wilkinson showed in 2008 (arXiv, Publ. IHES 2009) that the group of $C^{1}$-diffeomorphisms of a compact manifold $M$ contains a residual subset of diffeomorphisms whose centralizers are trivial.

Suppose that $\dim M \geq 2$. Is anything analogous to this known in the more restrictive setting of $\mathrm{Diff}^{1}_{\mathrm{vol}}(M)$, the group of $C^{1}$-diffeomorphisms of a compact manifold preserving a volume form?

Any comments / references are greatly appreciated! Thanks!

Edit: I am primarily interested in the group $\mathrm{Diff}^{\infty}_{\mu}(\mathbb{S}^2)$ of smooth diffeomorphisms of the $2$-sphere preserving the standard area form $\mu$. I asked the above question, since it is more closely connected to the work of Bonatti-Crovisier-Wilkinson. Of couse, if anyone knows anything specifically pertaining to $\mathrm{Diff}^{\infty}_{\mu}(\mathbb{S}^2)$, that would be great!

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    $\begingroup$ A very minor point: if $M$ is the circle, then I think volume-preserving diffeomorphisms will just be the rotations, so in fact they all commute. You may want to specify that $M$ has dimension at least two. $\endgroup$ Commented Apr 5, 2023 at 10:53
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    $\begingroup$ @MartinM.W. the rotation group is still cyclic (or more accurately, monothetic) as it is the closure of the cyclic group generated by one element (any irrational rotation). $\endgroup$
    – Asaf
    Commented Apr 5, 2023 at 11:55
  • $\begingroup$ @MartinM.W. Good point. I am in fact interested primarily in the case of the 2-sphere, so I can specify this. $\endgroup$ Commented Apr 5, 2023 at 12:28
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    $\begingroup$ Unimportant remark: The choice of the letter $\omega$ in $\mathrm{Diff}_\omega$ might be misread as analytic diffeomorphisms. $\endgroup$
    – YCor
    Commented Apr 5, 2023 at 12:42
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    $\begingroup$ As far as I know, the best characterization of the centralizer of generic area-preserving diffeomorphisms of the sphere $\mathbb{S}^2$ so far is given by the paper of Lizzie Burslem ams.org/journals/proc/2005-133-04/S0002-9939-04-07675-0/… $\endgroup$
    – Alejandro
    Commented Apr 5, 2023 at 13:42

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