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Essential surjectivity in Calkin descent for descendable maps

Establish the essential surjectivity of the canonical comparison functor Tot(Calk_κ(S^{⊗•})) → Calk_κ(R) for every descendable map of E∞-rings R → S and every uncountable regular cardinal κ, thereby proving that Calk_κ(R) ≅ Tot(Calk_κ(S^{⊗•})). In particular, prove the essential surjectivity for κ = ω₁. The comparison arises from the cosimplicial Cech nerve S^{⊗•} of R → S and the κ-Calkin construction on dualizable categories.

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Background

The paper develops continuous K-theory and localizing invariants for dualizable presentable stable categories, including the κ-Calkin construction Calk_κ(−), which extends the classical Calkin category to dualizable settings. In the context of fpqc and descendable topology, Proposition 1.92 shows that Mod-R satisfies descendable descent, and the authors compute Tot statements for associated invariants.

Remark 1.94 formulates a plausible generalization asserting an equivalence Calk_κ(R) ≅ Tot(Calk_κ(S{⊗•})) for descendable R → S, extending the descent framework from modules to κ-Calkin categories. The authors verify full faithfulness but indicate that essential surjectivity remains unresolved, even in the base case κ = ω₁.

References

It seems plausible that for any descendable map R Ñ S and for any uncountable regular cardinal κ we have an equivalence CalkκpRq » TotpCalk κS b‚`1qq. However, we only checked the fully faithfulness statement (the proof for κ ą ω 1 is the same). It is not clear how to prove the essential surjectivity even for κ “ ω .

K-theory and localizing invariants of large categories (2405.12169 - Efimov, 20 May 2024) in Remark 1.94, Section 1.16