Kernel theorems for rigidly-compactly generated infty-categories
Pith reviewed 2026-06-27 11:07 UTC · model grok-4.3
The pith
Contravariant linear functionals out of perfect objects are represented by (pseudo)-coherent objects in rigidly-compactly generated ∞-categories.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
In rigidly-compactly generated ∞-categories, contravariant linear functionals out of the category of perfect objects valued in (pseudo)-coherent objects are represented by (pseudo)-coherent objects, while covariant functionals out of coherent objects valued in coherent objects are represented by perfect objects.
What carries the argument
The interaction between compactness, dualizability, and coherence in presentable stable categories.
If this is right
- The theorems apply to E∞-ring spectra.
- The theorems apply to quasi-proper maps of quasi-compact quasi-separated schemes.
- The theorems apply to certain spectral algebraic spaces.
- Grothendieck duality admits a reformulation in terms of internal left adjoints.
Where Pith is reading between the lines
- The same representability pattern could be checked in other presentable stable categories satisfying the three finiteness conditions.
- The internal-left-adjoint reformulation of Grothendieck duality may simplify calculations involving dualizing objects in algebraic geometry.
- Analogous kernel theorems might exist when compactness is replaced by other finiteness notions in ∞-categories.
Load-bearing premise
The three notions of finiteness interact in the required way inside rigidly-compactly generated ∞-categories.
What would settle it
An explicit rigidly-compactly generated ∞-category together with a linear functional that cannot be represented by the predicted (pseudo)-coherent or perfect object.
Figures
read the original abstract
We prove two representability results for rigidly-compactly generated $\infty$-categories and functors between them. The first one represents contravariant linear functionals out of a category of perfect objects with values in a category of (pseudo)-coherent objects in terms of (pseudo)-coherent objects. The second one represents covariant functionals out of coherent objects with values in a category of coherent objects in terms of perfect objects. The techniques used belong to the realm of "functional analysis" of presentable stable categories and ultimately depend on the interaction between three notion of finiteness, namely compactness, dualizability and coherence. These results apply to $\mathbb{E}_\infty$-ring spectra, quasi-proper maps of quasi-compact quasi-separated schemes and certain spectral algebraic spaces. We also reformulate Grothendieck duality in terms of internal left adjoints.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proves two representability results (kernel theorems) for rigidly-compactly generated ∞-categories and functors between them. The first represents contravariant linear functionals out of the category of perfect objects, valued in (pseudo)-coherent objects, in terms of (pseudo)-coherent objects. The second represents covariant functionals out of coherent objects, valued in coherent objects, in terms of perfect objects. The arguments rely on techniques from the 'functional analysis' of presentable stable ∞-categories and the interaction of three notions of finiteness: compactness, dualizability, and coherence. Applications are given to E_∞-ring spectra, quasi-proper maps of qcqs schemes, and certain spectral algebraic spaces; Grothendieck duality is also reformulated in terms of internal left adjoints.
Significance. If the results hold, they supply useful representability theorems that extend classical duality and representability statements from algebraic geometry and stable homotopy theory into the setting of rigidly-compactly generated ∞-categories. The reformulation of Grothendieck duality and the explicit applications to ring spectra and schemes are concrete strengths. The work is grounded in prior notions of finiteness rather than ad-hoc constructions.
minor comments (4)
- §1 (Introduction): the precise definition of 'rigidly-compactly generated' is referenced to prior work but not restated; a short self-contained reminder would help readers who are not experts in the cited papers.
- §3.2, Definition 3.4: the notation for the (pseudo)-coherent objects is introduced without an explicit comparison to the classical coherent objects in the non-∞ setting; a remark clarifying the relationship would improve readability.
- Theorem 4.1 and Theorem 5.3: the statements are clear, but the proofs would benefit from an explicit pointer to the lemma that encodes the key interaction between compactness and dualizability (currently only implicit in the argument flow).
- References: several citations to Lurie's Higher Algebra and Spectral Algebraic Geometry are given by page number only; adding theorem or proposition numbers would make the dependencies easier to verify.
Simulated Author's Rebuttal
We thank the referee for their careful reading and positive evaluation of the manuscript. The recommendation for minor revision is noted, and we appreciate the recognition of the results' utility in extending classical duality statements to the setting of rigidly-compactly generated ∞-categories.
Circularity Check
No significant circularity; derivation self-contained
full rationale
The paper states two representability theorems for rigidly-compactly generated ∞-categories that rest on the interaction of compactness, dualizability and coherence. No equations, fitted parameters, self-definitional reductions or load-bearing self-citations are exhibited in the provided text that would make any claimed result equivalent to its inputs by construction. The work is presented as a proof relying on established notions of finiteness, with applications to ring spectra and schemes; the central claims therefore remain independent of the inputs they derive from.
Axiom & Free-Parameter Ledger
axioms (1)
- standard math Standard axioms and definitions of presentable stable ∞-categories, compactness, dualizability, and coherence as developed in prior literature.
Reference graph
Works this paper leans on
-
[1]
Higher Algebra , author =
-
[2]
preprint , publisher =
Spectral Algebraic Geometry , author =. preprint , publisher =
-
[3]
Higher Topos Theory (AM-170) , author =
-
[4]
The Stacks Project Authors , year =
-
[5]
2025 , eprint=
Triangulated categories with a single compact generator and two Brown representability theorems , author=. 2025 , eprint=
2025
-
[6]
Publications Math
Smoothness, semi-stability and alterations , author=. Publications Math
-
[7]
Advances in mathematics , publisher =
Enriched -categories via non-symmetric -operads , author =. Advances in mathematics , publisher =
-
[8]
Journal of the European Mathematical Society , volume=
Integral transforms for coherent sheaves , author=. Journal of the European Mathematical Society , volume=
-
[9]
Journal of the American Mathematical Society , volume=
Integral transforms and Drinfeld centers in derived algebraic geometry , author=. Journal of the American Mathematical Society , volume=
-
[10]
Grothendieck--Neeman duality and the Wirthm
Balmer, Paul and Dell’Ambrogio, Ivo and Sanders, Beren , journal=. Grothendieck--Neeman duality and the Wirthm. 2016 , publisher=
2016
-
[11]
Illinois Journal of Mathematics , volume=
Quasi-perfect scheme-maps and boundedness of the twisted inverse image functor , author=. Illinois Journal of Mathematics , volume=. 2007 , publisher=
2007
-
[12]
Ein Descente-Lemma und Grothendiecks Projektionssatz f
Kiehl, Reinhardt , year = 1972, journal =. Ein Descente-Lemma und Grothendiecks Projektionssatz f
1972
-
[13]
Mathematische Zeitschrift , volume=
Relative perfect complexes , author=. Mathematische Zeitschrift , volume=. 2023 , publisher=
2023
-
[14]
Berthelot, P and Jussila, O and Grothendieck, A and Raynaud, M and Kleiman, S and Illusie, L and Berthelot, Pierre and Illusie, L , year = 1971, publisher =. G
1971
-
[15]
Lecture Notes in Mathematics , publisher =
Th\'eorie des Intersections et Th\'eor\'eme de Riemann-Roch , author =. Lecture Notes in Mathematics , publisher =
-
[16]
Transactions of the American Mathematical Society , volume=
Construction of t -structures and equivalences of derived categories , author=. Transactions of the American Mathematical Society , volume=
-
[17]
International Mathematics Research Notices , publisher =
Weight structures and simple dg modules for positive dg algebras , author =. International Mathematics Research Notices , publisher =
-
[18]
Selecta Mathematica , publisher =
Homology of schemes , author =. Selecta Mathematica , publisher =
-
[19]
Journal f
Quasiexcellence implies strong generation , author=. Journal f. 2021 , publisher=
2021
-
[20]
Inventiones mathematicae , volume=
Projectivity of the Witt vector affine Grassmannian , author=. Inventiones mathematicae , volume=. 2017 , publisher=
2017
-
[21]
Compositio Mathematica , publisher =
A uniform treatment of Grothendieck's localization problem , author =. Compositio Mathematica , publisher =
-
[22]
Travaux de Gabber sur l'uniformisation locale et la cohomologie
-
[23]
Advances in Mathematics , publisher =
The Galois group of a stable homotopy theory , author =. Advances in Mathematics , publisher =
-
[24]
arXiv preprint math/0204218 , year=
Generators and representability of functors in commutative and noncommutative geometry , author=. arXiv preprint math/0204218 , year=
-
[25]
Geometry & Topology , publisher =
A universal characterization of higher algebraic K -theory , author =. Geometry & Topology , publisher =
-
[26]
Rings of quotients: an introduction to methods of ring theory , author =
-
[27]
1973 , publisher=
Popescu, Nicolae , series=. 1973 , publisher=
1973
-
[28]
Mattia Ornaghi , year = 2016, note =
2016
-
[29]
The passage among the subcategories of weakly approximable triangulated categories , author =
-
[30]
Journal of Pure and Applied Algebra , volume=
Faithfully flat descent of almost perfect complexes in rigid geometry , author=. Journal of Pure and Applied Algebra , volume=. 2022 , publisher=
2022
-
[31]
Annales de l'institut Fourier , volume=
Families of curves and alterations , author=. Annales de l'institut Fourier , volume=
-
[32]
2017 , url=
A Study in Derived Algebraic Geometry, Part 1: Volume I: Correspondences and Duality , author=. 2017 , url=
2017
-
[33]
2024 , eprint=
Locally rigid -categories , author=. 2024 , eprint=
2024
-
[34]
2013 , eprint=
Ideals in Triangulated Categories: Phantoms, Ghosts and Skeleta , author=. 2013 , eprint=
2013
-
[35]
2017 , eprint=
Higher traces, noncommutative motives, and the categorified Chern character , author=. 2017 , eprint=
2017
-
[36]
2025 , eprint=
Six-Functor Formalisms , author=. 2025 , eprint=
2025
-
[37]
Gluing approximable triangulated categories , volume=
Burke, Jesse and Neeman, Amnon and Pauwels, Bregje , year=. Gluing approximable triangulated categories , volume=. doi:10.1017/fms.2023.97 , journal=
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.