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Controlled theories give a functorial way to categorify and homotopify algebra, and produce a new model for ∞-groups.

Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →

T0 review · grok-4.5

2026-07-31 06:54 UTC pith:6HTMJAO4

load-bearing objection Solid new syntactic machine for controlled theories and realizations; the ∞-group model is plausible but rests on an unexpanded fiber-contractibility claim that the Picard case carefully proves. the 3 major comments →

arxiv 2607.24716 v1 pith:6HTMJAO4 submitted 2026-07-27 math.CT

Controlled theories, categorification, and homotopification

classification math.CT MSC 18C1018D2018N1055P48
keywords controlled theoriesLawvere theoriescategorificationhomotopificationinfinity-groupsE-infinity spacesenriched prosdeformations
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

Ordinary Lawvere theories are too rigid for higher algebra: they cannot encode coherent symmetries or inverses the way E∞-spaces and ∞-groups require. This paper introduces controlled theories—presentations of Lawvere theories equipped with a distinguished “control pro” that marks which operations should be weakened. Deformations of a controlled theory produce enriched Lawvere theories; two concrete functors then turn any controlled theory into a Lawvere 2-theory (algebraic realization) or a simplicial Lawvere theory (nerve realization). Applied to the controlled theory of groups, the nerve realization yields a projective model category of coherent group-like A∞-spaces that is Quillen equivalent to simplicial groups, hence a model for ∞-groups. The same machine builds coherent group-like E∞-spaces, proposed as a model for infinite loop spaces in later work, while deliberately keeping the non-contractible Z/2 data that earlier coherent-inverse approaches erased.

Core claim

A controlled theory (generators, control pro, and relations) can be deformed in any cartesian closed category; each deformation induces an enriched Lawvere theory. The algebraic and nerve realizations are functorial Ω*-free strong augmentations that convert controlled theories—and connected diagrams of them—into Lawvere 2-theories and simplicial Lawvere theories whose algebras are the desired weakened structures. In particular, the nerve realization of the group controlled theory, with the projective model structure, is a model for ∞-groups.

What carries the argument

Controlled theory plus deformation: a reduced signature G, a pro P mapped faithfully into the free Lawvere theory on G, and a full quotient to a Lawvere theory L; a deformation assigns contractible (or weakly equivalent) parameter spaces to the control operations and pushes out to an enriched Lawvere theory. Algebraic realization AR and nerve realization NR are the concrete functors implementing one-dimensional categorification and homotopification.

Load-bearing premise

The strictification map from the nerve realization of the group controlled theory to ordinary simplicial groups is a weak equivalence on every hom-object of simplicial sets.

What would settle it

Compute or exhibit a hom-object of the strictification map st : NR(Ω_grp) → D(G) that is not a weak equivalence of simplicial sets; if any such fiber fails to be contractible, the Quillen equivalence claimed for A^gl_∞-Spaces collapses.

Watch this falsifier — get emailed when new claim-graph text bears on it.

If this is right

  • The projective model structure on algebras for the nerve realization of the group controlled theory is a model for ∞-groups.
  • Coherent group-like E∞-spaces arise as the pullback of A^gl_∞-spaces and E∞-spaces and are the proposed input for an infinite-loop-space machine.
  • Connected diagrams of controlled theories realize to colimits of Lawvere 2-theories (or simplicial theories) whose algebras are the corresponding limits of algebra categories.
  • The Picard controlled theory’s strictification is not a weak equivalence, retaining a non-trivial Z/2 automorphism of the identity that earlier contractible-inverse approaches discarded.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same control-and-deform pattern should extend to unbiased higher groups and connective spectra once multi-dimensional or operadic control pros are supplied.
  • A direct comparison of the coherent group-like E∞-space category with classical infinite-loop-space machines would test the paper’s future-work claim before the sequel appears.
  • Admissible replacement and P-structured presentations suggest controlled theories factor free functors from PROPs (and other structured pros) into Lawvere theories, giving a uniform source of weakened algebraic models beyond groups.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

3 major / 6 minor

Summary. The paper introduces "controlled theories" — a presentation of a Lawvere theory L by a reduced signature G together with a faithful "control pro" P tracking a distinguished part of the free theory Fr(G) — and a notion of deformation of such theories in a cartesian closed category V, producing V-enriched Lawvere theories. Two functorial constructions are given: algebraic realization AR : cTh → 2Law (using the indiscrete category E([f]) on reduced classes) and nerve realization NR : cTh → sSetLaw. Applications: NRΩ_mon recovers A∞-spaces (Prop. 6.18), NRΩ_cm recovers E∞-spaces (Prop. 6.20), and the projective model structure on A^gl_∞-Spaces := Alg(NRΩ_grp, sSet) is claimed to model ∞-groups via a Quillen equivalence with simplicial groups (Thm. 6.19). A contrasting negative result (Prop. 6.15 / Thm. 6.21) shows the Picard strictification st : NRΩ_pic → D(A) is not a weak equivalence, because the fiber over id_1 carries the Z/2 "trace" automorphism. The E^gl_∞-spaces pullback is constructed and deferred to future work as a proposed model for infinite loop spaces.

Significance. If the central claims hold, the paper gives a uniform, syntactic machine producing categorifications and homotopifications of algebraic theories with the coherence weakening controlled at specified locations — a genuinely useful organizational tool, and one that explains concretely why the Schwänzl–Vogt contractibility hypothesis fails (the explicit Z/2 computation in Prop. 6.15 and the lift-free ∂∆² argument in Thm. 6.21 are the paper's best moments: concrete, checkable, and illuminating). The claimed new model for ∞-groups would be a falsifiable, model-category-level statement, and the E^gl_∞ program makes a testable prediction about infinite loop spaces. However, the two headline positive applications (A^gl_∞ as a model for ∞-groups, and the identification with A∞/E∞ algebras) currently rest on asserted-but-unproven local contractibility properties, so the significance is conditional on closing those gaps.

major comments (3)
  1. [§6, Theorem 6.19] The proof of Theorem 6.19 is incomplete at its load-bearing step. Rezk's Corollary 8.6 (equivalently Berger–Moerdijk Thm. 4.1) requires st : NRΩ_grp → D(G) to be a weak equivalence of simplicial Lawvere theories, i.e. a weak equivalence on every hom-simplicial-set. The proof simply asserts 'whose morphisms on hom-objects are weak equivalences of simplicial sets' with no verification. What is needed is a computation of NRΩ_grp(n,k): by Construction 6.9 it should be a coproduct over reduced classes [f] ∈ Ω_grp(n,k) of nerves NE([f]), each contractible when [f] ≠ ∅. This requires (i) every class [f] is nonempty (fullness of st : Fr(G) → G gives this), (ii) the pushout defining L_O in §5.33 introduces no extra components or identifications in hom-objects, and (iii) contractibility of each NE([f]). Point (iii) is genuinely nontrivial for the group theory: it is the simplicial shadow of the cl
  2. [§6, Propositions 6.18 and 6.20] The same gap affects the A∞ and E∞ identifications. After Proposition 6.18, the text asserts 'This morphism is a weak equivalence in sSTh' for st : NRΩ_mon → D(M) with no argument; here the verification is short (Ω_mon(n,1) is a singleton and fibers NE([f]) are contractible), but it should be given, including the claim Ω_mon(n,1) ≅ *. More seriously, Proposition 6.20 disposes of the E∞ case with 'Repeat the proof ... making sure to account for the symmetric group actions coming from the deformation structure.' For E to be an E∞-operad one needs each E_n to be a contractible Σ_n-free Σ_n-space; the freeness is exactly the Ω*-freeness condition of Definition 6.7, and its instance for Ω_cm is never checked for the nerve realization (Theorem 6.17's one-line Ω*-freeness inheritance does not address the Σ_n-action freeness). Without this, 'E is an E∞-operad' and hence the identification Alg(NR
  3. [§6, Theorem 6.10] The proof of Theorem 6.10 (and its nerve analogue, Theorem 6.17) that the algebraic augmentation is Ω*-free consists of the single sentence 'Notice that the diagram of 2 holds if and only if f is the identity.' Given that Ω*-freeness (Definition 6.7, diagram (2)) is the paper's replacement for Σ-freeness and is used to motivate the good behavior of the realizations, this deserves an actual argument: one must show that for an invertible f ∈ Ω*(n,n) with [g∘f] = [g], the composition map Γ : O_[g] × O_[f] → O_[g∘f] is compatible with the identity on O_[g] only at f = id_n, using the indiscrete structure of E([f]). As written, the reader cannot verify the claim without redoing the construction.
minor comments (6)
  1. [§6, Construction 6.16 / Theorem 6.17] Terminology inconsistency: Construction 6.16 defines the 'nerve augmentation' NA_Ω, but Theorem 6.17 states and proves a result about the 'classifying augmentation,' a term never defined. Presumably these are the same object.
  2. Typos and grammatical issues: 'We our motivated by this lemma' (before Example 4.9); 'The three controlled theories that we consider in this papers' (§4, before Construction 4.12); 'a symmetric monoidal category closed category' (Definition 3.20); 'proof of functorality' (after Lemma 3.22); 'Schwanz and Vogt' for Schwänzl and Vogt throughout the introduction.
  3. [§4, Definition 4.6] Definition 4.6 defines objects of Diag(cTh) as pairs (I,D) but then writes the diagram as J : I → cTh; the notation D/J is used interchangeably in the display. Also, N is used for both the natural numbers and the nerve functor; in §6 this becomes confusing (e.g., 'the nerve functor N : Cat → sSet' alongside n ∈ N indexing).
  4. [§1, Introduction] The introduction states that 'it is well-known that there is no Lawvere theory whose homotopy algebras ... model the E∞-spaces' while acknowledging this is 'not explicitly written anywhere.' This should either be proved, given a precise reference (e.g., a corollary of Badzioch's rigidity results), or softened to a heuristic remark.
  5. [§6, Example 6.13] Example 6.13's dependence on [Parab, 2025] (an unpublished Ph.D. thesis) for the biequivalence st : ARΩ_grp → D(G) should be flagged more prominently, with the precise statement of Theorem 10.3.33 reproduced, since this appears to be the intended ingredient for the contractibility needed in Theorem 6.19. Similarly, the model structure on 2Law attributed to [Yanofsky, 2000] in the future-work section is an arXiv preprint; its status should be noted.
  6. [§6, Proposition 6.15] Proposition 6.15 is labeled 'Proposition' in the text but referred to as part of 'Theorem 6.21' in the introduction's theorem list; please harmonize numbering/cross-references.

Circularity Check

1 steps flagged

No load-bearing circularity: main claims rest on external model-category criteria and explicit constructions, with only a non-load-bearing thesis self-citation for origin of controlled theories.

specific steps
  1. self citation load bearing [Abstract; §1 Introduction; references [Taylor, 2026]]
    "we introduce the notion of a controlled theory, originally developed in the author's thesis, as a structural tool for the study of higher categorical algebra."

    Minor origin citation only. The paper supplies full internal definitions (Def. 4.1, admissible replacement, deformations, AR/NR functors) and does not rest Theorem 6.19 or 6.21 on an unverified uniqueness or rectification result from the thesis. Not load-bearing for the claimed models.

full rationale

The paper defines controlled theories, deformations, algebraic/nerve realizations, and the categories A^gl_∞-Spaces and E^gl_∞-Spaces in full within the text (Defs. 4.1–4.16, Constructions 6.9 and 6.16, §§5–6). Theorem 6.19 asserts a Quillen equivalence via st: NRΩ_grp → D(G) and Rezk’s Corollary 8.6 plus the classical fact that simplicial groups model connective types; that assertion may be under-proved (a correctness gap), but it is not forced by definition of the input data, nor by fitting a parameter, nor by a uniqueness theorem imported from the author. Theorem 6.21 is an explicit non-contractibility calculation on st^{-1}(id_1) and is independent. The only self-reference is the abstract/intro note that controlled theories originated in the author’s thesis; the paper re-develops the definitions and does not use the thesis as a uniqueness or rectification black box for the ∞-group or non-equivalence claims. No self-definitional loop, fitted-as-prediction, or renaming-of-known-result pattern appears in the derivation chain.

Axiom & Free-Parameter Ledger

0 free parameters · 5 axioms · 4 invented entities

The work sits on standard enriched category theory, model-category rectification theorems, and classical coherence results. No numerical free parameters appear. The main invented package is the controlled-theory / deformation apparatus itself; independent evidence is partial (recovers known coherence theorems and produces a Quillen-equivalent model of ∞-groups) but the infinite-loop-space claim is explicitly deferred.

axioms (5)
  • standard math Local presentability of Sig, rSig, Pro, Law and of the corresponding V-enriched categories when V is locally presentable cartesian closed (used throughout §§2–5).
    Invoked to obtain free functors and adjoints via the adjoint-functor theorem.
  • standard math Rezk’s Corollary 8.6 / Berger–Moerdijk rectification: a map of simplicial Lawvere theories that is objectwise a weak equivalence induces a Quillen equivalence on projective algebra categories.
    Load-bearing for Theorems 6.19 and the A∞/E∞ comparisons.
  • domain assumption Simplicial groups (with the projective/standard model structure) model connective homotopy types / ∞-groups.
    Used in the last sentence of the proof of Theorem 6.19 to conclude that A^gl_∞-Spaces models ∞-groups.
  • standard math The nerve functor N : Cat → sSet preserves products (so that the nerve of an algebraic augmentation remains a deformation).
    Stated in Construction 6.16; needed for NR to land in sSet-Lawvere theories.
  • domain assumption Classical coherence theorems for monoidal and symmetric monoidal categories (Mac Lane) and for coherent 2-groups (cited via Parab 2025).
    Used to identify the algebras of AR Ω_mon, AR Ω_cm, AR Ω_grp with the expected 2-categorical structures.
invented entities (4)
  • Controlled theory (signature + control pro + presentation map) independent evidence
    purpose: Specify which fragment of a free theory is tracked when axioms are weakened for categorification/homotopification.
    Central new organizing device; every subsequent construction is built from it.
  • Deformation of a pro / of a controlled theory in a cartesian closed category independent evidence
    purpose: Parametrize operations by objects of V so that composition and units are coherent, inducing enriched pros and Lawvere theories.
    Technical engine that turns control data into enriched algebraic theories.
  • Algebraic realization functor AR : cTh → 2Law and nerve realization NR : cTh → sSetLaw independent evidence
    purpose: Functorially produce Lawvere 2-theories and simplicial Lawvere theories from controlled theories (and from connected diagrams thereof).
    Delivers the categorified and homotopified models claimed in the abstract.
  • A^gl_∞-Spaces and E^gl_∞-Spaces no independent evidence
    purpose: Concrete model categories of coherent group-like A∞-spaces and coherent group-like E∞-spaces.
    Primary applications; the former is claimed to model ∞-groups, the latter is promised to model infinite loop spaces.

pith-pipeline@v1.2.0-grok45-kimik3 · 35441 in / 3500 out tokens · 59403 ms · 2026-07-31T06:54:53.419739+00:00 · methodology

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read the original abstract

In this paper, we introduce the notion of a controlled theory, originally developed in the author's thesis, as a structural tool for the study of higher categorical algebra. We define a notion of deformation for pros and controlled theories in a cartesian closed category. Furthermore, we show that deformations of controlled theories naturally produce Lawvere theories enriched over the same base category. We construct functorial one-dimensional categorifications and homotopifications of controlled theories, yielding Lawvere $2$-theories and Lawvere theories enriched in simplicial sets, respectively. As an application, we obtain a new model for $\infty$-groups and construct a model of coherent group-like $E_\infty$-spaces, which we will show in future work models infinite loop spaces.

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Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Algebraic coherators, controlled theories, and Grothendieck realizations

    math.CT 2026-07 conditional novelty 5.5

    Algebraic coherators and Grothendieck realizations produce infinity-Lawvere theories for monoidal and Picard infinity-groupoids; a generalized pushout conjecture would yield semi-model structures and the Homotopy Hypothesis.

Reference graph

Works this paper leans on

25 extracted references · 5 linked inside Pith · cited by 1 Pith paper

  1. [1]

    Ad´ amek and J

    [Ad´ amek and Rosick´ y, 1994] J. Ad´ amek and J. Rosick´ y,Locally Presentable and Accessible Categories. Cambridge University Press, Cambridge,

  2. [11]

    [May, 1972] J

    Cambridge University Press, London, 1974, 61–94. [May, 1972] J. P. May,The Geometry of Iterated Loop Spaces. Lecture Notes in Mathematics

  3. [16]

    Mac Lane,Natural Associativity and Commutativity

    [Mac Lane, 1963] S. Mac Lane,Natural Associativity and Commutativity. Rice Univ. Stud.49(1963), no. 4, 28–46. [Maltsiniotis, 2005] G. Maltsiniotis,La th´ eorie de l’homotopie de Grothendieck. Ast´ erisque301(2005), vi+140 pp. [May, 1974] J. P. May,E ∞ spaces, group completions, and permutative categories. InNew Developments in Topology, London Mathematica...

  4. [23]

    Ugleˇ si´ c,Enriched pro-categories and shapes

    [Ugleˇ si´ c, 2019] N. Ugleˇ si´ c,Enriched pro-categories and shapes. arXiv:1905.07181 [math.CT],

  5. [24]

    Uustalu,Coherence for skew-monoidal categories

    [Uustalu, 2014] T. Uustalu,Coherence for skew-monoidal categories. InProceedings of the 5th Workshop on Mathematically Structured Functional Programming, Electron. Proc. Theor. Comput. Sci.153 (2014), 68–77. [Yanofsky, 2000] N. S. Yanofsky,Coherence, Homotopy and 2-Theories. arXiv:math/0007033 [math.CT],

  6. [34]

    Gurski, N

    [Gurski, Johnson, and Osorno, 2019] N. Gurski, N. Johnson, and A. M. Osorno,The 2-dimensional stable homotopy hypothesis. J. Pure Appl. Algebra223(2019), no. 10, 4348–4383. [Henry and Lanari, 2023] S. Henry and E. Lanari,On the homotopy hypothesis for 3-groupoids. Theory Appl. Categ.39(2023), Paper No. 26, 735–768. [Hirschhorn, 2003] P. S. Hirschhorn,Mode...

  7. [1967]

    Riehl and D

    [Riehl and Verity, 2020] E. Riehl and D. Verity,Infinity Category Theory from Scratch. Higher Struc- tures4(2020), no. 1, 115–167. CONTROLLED THEORIES, CATEGORIFICATION, AND HOMOTOPIFICATION57 [Rezk, 2002] C. Rezk,Every Homotopy Theory of Simplicial Algebras Admits a Proper Model. Topology Appl.119(2002), no. 1, 65–94. [Schw¨ anzl and Vogt, 1989] R. Schw¨...

  8. [1972]

    [May and Thomason, 1978] J. P. May and R. Thomason,The uniqueness of infinite loop space machines. Topology17(1978), no. 3, 205–224. [McDermott and Uustalu, 2022] D. McDermott and T. Uustalu,What Makes a Strong Monad?. Elec- tron. Proc. Theor. Comput. Sci.360(2022), 113–133. [Muro, 2015] F. Muro,Dwyer–Kan homotopy theory of enriched categories. J. Topol.8...

  9. [1982]

    [Kelly and Lack, 2001] G. M. Kelly and S. Lack,V-Cat is locally presentable or locally bounded ifVis so. Theory Appl. Categ.8(2001), 555–575. [Lanari, 2018] E. Lanari,A semi-model structure for Grothendieck weak 3-groupoids. Preprint,

  10. [1994]

    [Anderson, 1972] D. W. Anderson,Fibrations and geometric realizations. Bull. Amer. Math. Soc.78 (1972), no. 4, 521–525. [Ara, 2013] D. Ara,On the homotopy theory of Grothendieck∞-groupoids. J. Pure Appl. Algebra217 (2013), no. 7, 1237–1278. CONTROLLED THEORIES, CATEGORIFICATION, AND HOMOTOPIFICATION55 [Baez and Williams, 2020] J. C. Baez and C. Williams,E...

  11. [1997]

    [Elmendorf and Mandell, 2006] A. D. Elmendorf and M. A. Mandell,Rings, Modules, and Algebras in Infinite Loop Space Theory. Adv. Math.205(2006), no. 1, 163–228. [Fong and Spivak, 2019] B. Fong and D. I. Spivak,An Invitation to Applied Category Theory: Seven Sketches in Compositionality. Cambridge University Press, Cambridge,

  12. [1998]

    Johnson and A

    [Johnson and Osorno, 2012] N. Johnson and A. M. Osorno,Modeling stable one-types. Theory Appl. Categ.26(2012), no. 20, 520–537. [Johnson and Yau, 2020] N. Johnson and D. Yau,2-Dimensional Categories. Oxford University Press, Oxford,

  13. [1999]

    [Goerss and Schemmerhorn, 2007] P. G. Goerss and K. Schemmerhorn,Model Categories and Simplicial Methods. InInteractions Between Homotopy Theory and Algebra, Contemp. Math.436. Amer. Math. Soc., Providence, RI, 2007, 3–49. [Grothendieck, 2022] A. Grothendieck,Pursuing Stacks (` a la poursuite des champs). Vol. I. Documents Math´ ematiques

  14. [2000]

    Yau,Colored Operads

    [Yau, 2016] D. Yau,Colored Operads. Graduate Studies in Mathematics

  15. [2003]

    Hovey,Monoidal Model Categories

    [Hovey, 1998] M. Hovey,Monoidal Model Categories. arXiv:math/9803002 [math.AT],

  16. [2004]

    Lurie,Higher Topos Theory

    [Lurie, 2009] J. Lurie,Higher Topos Theory. Annals of Mathematics Studies

  17. [2008]

    [Joyal, Street, and Verity, 1996] A

    Available athttps://www.math.uchicago.edu/ ~may/IMA/Joyal.pdf. [Joyal, Street, and Verity, 1996] A. Joyal, R. Street, and D. Verity,Traced Monoidal Categories. Math. Proc. Cambridge Philos. Soc.119(1996), no. 3, 447–468. [Kelly, 1982] G. M. Kelly,Basic Concepts of Enriched Category Theory. London Mathematical Society Lecture Note Series

  18. [2009]

    Dugger,Coherence for invertible objects and multigraded homotopy rings

    [Dugger, 2014] D. Dugger,Coherence for invertible objects and multigraded homotopy rings. Algebr. Geom. Topol.14(2014), no. 2, 1055–1106. [Dwyer, Hirschhorn, and Kan, 1997] W. G. Dwyer, P. S. Hirschhorn, and D. M. Kan,Model Categories and More General Abstract Homotopy Theory. Unpublished manuscript,

  19. [2018]

    [Lawvere, 1963] F. W. Lawvere,Functorial semantics of algebraic theories. Proc. Natl. Acad. Sci. USA 50(1963), 869–872. [Lawvere, 2002] F. W. Lawvere,Metric Spaces, Generalized Logic, and Closed Categories. Repr. Theory Appl. Categ.1(2002), 1–37. [Leinster, 2004] T. Leinster,Higher Operads, Higher Categories. London Mathematical Society Lecture Note Series

  20. [2019]

    [Goerss and Jardine, 1999] P. G. Goerss and J. F. Jardine,Simplicial Homotopy Theory. Progress in Mathematics

  21. [2020]

    Joyal,The Theory of Quasi-Categories and Its Applications

    56JOHNATHON TAYLOR [Joyal, 2008] A. Joyal,The Theory of Quasi-Categories and Its Applications. Lecture notes,

  22. [2022]

    Gurski and N

    [Gurski and Johnson, 2026] N. Gurski and N. Johnson,Invertibility and Parity in Symmetric Monoidal Categories. Appl. Categ. Structures34(2026), Article

  23. [2023]

    [Perutka, 2026] T

    Available athttps://topos.institute/blog/2023-08-15-unbiased-pseudomonoids/. [Perutka, 2026] T. Perutka, 2-Dimensional Lawvere Theories, Commutativity, and Higher Day Convo- lution. arXiv:2602.14332 [math.CT],

  24. [2025]

    Patterson,Unbiased monoidal categories are pseudo-elements

    [Patterson, 2023] E. Patterson,Unbiased monoidal categories are pseudo-elements. Topos Institute Blog,

  25. [2026]

    [Quillen, 1967] D. G. Quillen,Homotopical Algebra. Lecture Notes in Mathematics