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Bounded t-structure on the kernel MV_0(X, D) in higher dimensions

Determine whether, for semi-simplicial sets X of dimension greater than one with smooth G-action and any admissible collection D of subcategories, the pointwise t-structure on MV(X, D)^ω restricts to a bounded t-structure on the kernel MV_0(X, D)^ω (the kernel of α: MV(X, D) → D(G)), i.e., whether both truncation functors preserve MV_0(X, D)^ω and induce a bounded t-structure.

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Background

The authors construct MV(X, D) as a compactly generated stable category of Mayer–Vietoris resolutions and show in rank-one cases that the kernel MV_0(X, D) inherits a bounded t-structure, enabling devissage and heart arguments for K-theory computations.

They note that when the building has dimension greater than one, it is not clear whether this bounded t-structure persists on MV_0(X, D)ω. They explain implications (e.g., vanishing of K_{−1} and surjectivity on K_0 of the assembly map) and observe that recent results of Bartels–Lück remove certain obstructions, but the structural question about the t-structure restriction remains unresolved.

References

If the dimension of X is greater than one it is not clear that the $t$-structure on $MV(X, \mathcal{D})\omega$ restricts to a (bounded) $t$-structure on $MV_0(X, \mathcal{D})\omega$.

K-theory of rank one reductive p-adic groups and Bernstein blocks (2407.14929 - Tönies, 20 Jul 2024) in Section 3.2, Remark following Lemma 3.2 (tker)