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Equivariant equivalence between Rognes’s common basis complex and the suspension of the minimal spanning poset nerve

Establish a GL_k(R)-equivariant weak equivalence between the common basis complex Σ^{-1} D^V(R^k) and the unreduced suspension Σ N P^∘, where R is a commutative ring, D^V(R^k) is Rognes’s common basis complex for R^k, and P^∘ is the poset of nontrivial minimal spanning posets in the subobject structure Sub_{R^k}.

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Background

In Section 4.3, the authors reinterpret Rognes’s poset filtration for the spectrum D(Rk) by introducing a valuation taking simplices to their submodule configurations, which form minimal spanning posets in Sub_{Rk}. They identify D(Rk) ≃ Σ Σ N P in a GL_k(R)-equivariant manner, where P consists of nontrivial minimal spanning posets.

Rognes also showed D(Rk) ≃ Σ Σ (Σ{-1} DV(Rk)), with DV(Rk) the common basis complex. Comparing these decompositions leads to a conjectured equivalence between Σ{-1} DV(Rk) and Σ N P∘, refined to hold GL_k(R)-equivariantly.

References

we get the following conjecture:

$GL_k(R)$-equivariantly, \Sigma{-1}DV(Rk) \simeq \Sigma N\P\circ.

A stable rank filtration on direct sum $K$-theory (2501.01609 - Campbell et al., 3 Jan 2025) in Section 4.3 (Rognes’s poset filtration)