Pith. sign in

REVIEW 3 major objections 4 minor 46 references

Representation stability for ordered Hurwitz spaces

T0 review · 3 major / 4 minor · reviewed 2026-08-05 · deepseek-v4-flash

Pith's one-line read Ordered Hurwitz homology stabilizes representationally.

desk verdict New and correct-looking answer to Ellenberg's problem; the Shusterman-input verification gap is real but fixable, and the paper deserves a serious referee, not a desk reject. read the letter →

arxiv 2509.05516 v1 pith:YKN2EKT3 submitted 2025-09-05 math.AT math.NT

classification math.ATmath.NT MSC 55R8020C30
keywords orderedHurwitzspacesrepresentationstabilitysymmetricgrouprepresentationsbraidgroupsquandleshomologicalFI-modulesbranchedcovers
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

This paper proves that the rational homology of ordered Hurwitz spaces — moduli spaces of branched covers with a chosen ordering on the branch points — carries a representation-theoretic stability phenomenon. For any finite group G and conjugacy class c satisfying the non-splitting property, the homology groups H^i(OHur^c_{G,n}; Q), viewed as representations of the symmetric group permuting the branch order, have irreducible multiplicities that are independent of n once n is at least a linear function of i. This answers a question posed at a 2019 problem session and refines earlier homological stability results for unordered Hurwitz spaces, where only the total dimension stabilizes. Because the stability is uniform across all irreducible representations, it implies that these Betti numbers agree with integer-valued polynomials and that ordered Hurwitz homology is finitely generated as a module over a Hurwitz analogue of the category FI.

What carries the argument

The proof is carried by the FB-space OHur^c_G (the ordered Hurwitz space with its permutation action) treated as a monoid under Day convolution, and by its derived indecomposables Q^L(OHur)(π0(OHur)). A functorial resolution R^▲(M), adapted from a semi-simplicial resolution used for configuration spaces in the literature, models these derived indecomposables. The resolution collapses (for set-valued modules) to an ordered version of the Koszul-like complex of the Hurwitz stability literature, whose vanishing in a linear range follows from a theorem asserting that, for connected finite quandles, pure braid orbits eventually coincide with full braid orbits. This vanishing is the input that let

What would settle it

Take any pair (G,c) satisfying the non-splitting property, such as c a generating conjugacy class with c∩H always empty or a single H-conjugacy class, and compute the first non-trivial homology H^1(OHur^c_{G,n};Q) for n in the claimed stable range; if the multiplicity of a fixed irreducible V^{(n-|λ|,λ)}_n changes with n, Theorem 1.1 is false. More directly, search for a connected finite quandle X and arbitrarily large n with a generating tuple x ∈ X^n whose pure braid orbit is a proper subset of its braid orbit, which would contradict the quandle theorem the proof depends on.

Watch

Extended reading notes

Core claim

The central claim is Theorem 1.1: for a finite group G and a conjugacy class c with the non-splitting property, there are constants α and β depending only on (G,c) such that the sequence {H^i(OHur^c_{G,n}; Q)}_n is uniformly multiplicity stable with stable range α i + β. In plain terms, the number of times each irreducible symmetric-group representation appears in the homology of the n-point ordered Hurwitz space stops changing for n large enough, and the threshold grows linearly with the homological degree. The paper proves this by building a functorial resolution of modules over the ordered Hurwitz monoid, identifying the resulting derived indecomposables with the homology of an ordered 'K

Load-bearing premise

The proof rests on a cited theorem (Theorem 7.5) that for any connected finite quandle, the pure braid group orbit and the full braid group orbit of every generating tuple coincide once the number of strands is large enough; if that theorem fails, the identification of the components of ordered and unordered Hurwitz spaces in a range fails and the main vanishing result does not follow. The non-splitting property and invertibility of |G| in the coefficient field are also used

Editorial extensions

If this is right

  • Dimensions of H^i(OHur^c_{G,n};Q) agree with an integer-valued polynomial in n in the stable range, so the ordered Hurwitz Betti numbers have eventual polynomial growth (Corollary 1.2).
  • Uniform multiplicity stability implies the representation M_n determines M_{n+1} in the stable range, so finite data determines all higher homology representations (Definition 9.3).
  • Because the trivial representation is among the stabilized irreducibles, Theorem 1.1 recovers the homological stability of unordered Hurwitz spaces as coinvariants.
  • Each H^i(OHur^c_G) is generated in degrees at most a i + b as a module over the category FI(c), a Hurwitz analogue of FI (Corollary 1.3).

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The constants α and β are not made explicit; if tracked, the proof would yield effective stable ranges and hence a finite computation of all homology representations.
  • The orbit-coincidence input suggests that, in the stable range, ordering the branch points acts homologically like a free permutation of indistinguishable labels; this could make ordered Hurwitz homology a 'free' refinement of unordered Hurwitz homology.
  • The FI(c)-module generation result may open the door to secondary stability or to polynomial functor results analogous to those for FI-modules, connecting ordered Hurwitz homology to arithmetic statistics in function fields.
  • If the quandle-orbit theorem holds beyond conjugacy classes satisfying the non-splitting property, the main argument may extend to more general conjugation-invariant subsets or infinite groups.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 4 minor

Summary. The paper proves that, for a finite group G and a conjugacy class c satisfying the non-splitting property, the homology groups H_i(OHur^c_{G,n}; Q), viewed as a sequence of Sigma_n-representations, have uniform multiplicity stability with a stable range linear in i. The proof adapts the MPPRW framework of uniform twisted homological stability to ordered Hurwitz spaces, building a resolution of modules over the monoid OHur^c_G, identifying the relevant derived indecomposables with an ordered analogue of the Ellenberg--Venkatesh--Westerland Koszul complex, and proving vanishing in a range using a theorem of Shusterman and a double-complex argument. The authors also define a Hurwitz analogue FI(c) of the category FI and derive polynomial growth of Betti numbers as a corollary.

Significance. If the proof is correct, the paper answers a question of Ellenberg and substantially extends the homological stability results of Ellenberg--Venkatesh--Westerland from unordered to ordered Hurwitz spaces. The explicit linear stable range and the introduction of the category FI(c) are useful contributions. The paper also gives an explicit description of derived indecomposables and a clean categorical framework that is likely to be reusable. The central claim is independent of the authors' previous work, and the reliance on external results (EVW16, Shusterman, Davis--Schlank, GKRW, MPPRW) is clearly signaled. The main risk is a load-bearing but insufficiently verified reformulation of Shusterman's theorem, as detailed below.

major comments (3)
  1. [§7, Theorem 7.5 and Corollary 7.6] Corollary 7.6 is the linchpin of the vanishing theorem: it identifies pi_0(OHur^c_{G,n}) with pi_0(Hur^c_{G,n}) for all n >= N_c, and this identification is used in Corollary 7.7, Lemma 7.16, and Theorem 7.18. The proof applies Theorem 7.5 to the subquandle c∩H_V for each subset V of entries. However, Theorem 7.5 is only stated as a 'reformulation of a special case' of [Shu24, Theorem 2.4], and three points need independent verification: (i) whether Shusterman's N_X is uniform over all generating n-tuples simultaneously or may depend on the tuple; (ii) whether 'generating' in the source means quandle-generation, as used here; (iii) whether the subquandle c∩H_V is indeed connected for the non-splitting pairs considered, including when V is the underlying set of a tuple with repeated entries. If N_X is not uniform over tuples, the maximum over V⊆c in Corollary 7.6 is unjustified, and the s
  2. [§7, Lemma 7.11] The proof of Lemma 7.11 is a sketch: the chain homotopy H_g is defined, but the 'routine calculation' that it is a chain homotopy between the zero map and the map in Formula (4) is not shown, and the existence of the braid b that identifies the two maps is asserted without proof. This lemma is load-bearing because it implies that multiplication by a single element g induces the zero map on the homology of the ordered Koszul complex rK_*, which is essential for the spectral sequence argument in Theorem 7.18. Since the cited EVW Lemma 4.11 concerns the unordered complex and the present setting involves pure braid groups, the translation to the ordered setting needs to be written out in full or supplied with a precise reference to a proved ordered analogue.
  3. [§9, Proposition 9.1] Proposition 9.1 states that the twisted homology groups H_i(((OHur^c_G)_K ⊛ Sigma^r V(lambda)) / rU)_n^hFB vanish for n >= A i + r + B, and the proof is deferred with the sentence 'The proof is the same as that of [MPPRW, Theorem 2.2].' Since Proposition 9.1 is the direct input to Theorem 9.4 and to the finite generation of M over H_0(Hur^c_G), a more complete argument is needed: the hypotheses of [GKRW, Theorem 11.21] should be checked in this setting, and the spectral sequence indexing and the cellular approximation step should be supplied. Without this, the chain from vanishing of derived indecomposables to uniform multiplicity stability is not fully documented.
minor comments (4)
  1. [Abstract and §1] Typo: 'exhibt' should be 'exhibit' in the abstract and again in the introduction.
  2. [Corollary 7.6] The displayed definition of N_c reads 'Nc=max_{V⊆c} pHVq'; this appears to be a typo for 'N(H_V)' and should be corrected.
  3. [Corollary 7.7] The statement gives isomorphisms for p <= n - N_c - 1 and a surjection for p = n - N_c, but the preceding chain complex is defined for p >= -1. It would help to specify the exact range of p for which the boundary case applies, since the identification of rK_{n-N_c}(n) is used in the double complex in Section 7.
  4. [Section 10, Remark 10.2] The parenthetical '(e.g., when G is abelian)' claims that pure braid group actions are trivial in that case; this is true for the action on c^n for a conjugacy class in an abelian group, but the sentence could be phrased more carefully to avoid ambiguity between the group action on tuples and the monodromy labels.

Circularity Check

0 steps flagged · score 2.0 of 10

No significant circularity; central argument rests on external results of Shusterman, EVW, and Davis–Schlank. Minor methodological self-citations are not load-bearing.

full rationale

The main theorem (Thm 1.1 / Thm 9.4) derives uniform multiplicity stability for H^i(OHur^c_{G,n};Q) from (i) a vanishing theorem for derived indecomposables (Thm 7.18), (ii) a twisted homological stability argument following MPPRW, and (iii) a finite-generation input from Davis–Schlank (Thm 9.2). The vanishing theorem is itself built from Cor 7.6, which identifies pi_0(OHur) with pi_0(Hur) in a range. That corollary is proved by applying Shusterman's Theorem 7.5 to the subquandles c∩H_V. Shusterman is external work with no author overlap; EVW's Lemma 7.8 supplies the periodicity element U, and Davis–Schlank supplies the finiteness theorem. None of these inputs assumes the target representation stability. The paper's self-citations—mainly [MPPRW] (J. Miller is a coauthor) for the uniform-twisted-stability framework and [KLM+24] (also coauthored by Miller) for Lemma 7.14—are methodological: the relevant proofs are reproduced or adapted in the text, and the load-bearing vanishing/stability inputs are external. A genuine caveat, explicit in the text, is that Theorem 7.5 is quoted as “a reformulation of a special case” of [Shu24, Theorem 2.4], and the uniformity and ‘generating’ quantifiers are not verified for the subquandles c∩H_V before taking the maximum in Cor 7.6. If Shusterman's theorem has different quantifier structure, Cor 7.6 and hence Thm 7.18 could fail. That is a correctness risk in an external dependency, not circularity: the argument would break, but it would not reduce to its own conclusion. No fitted parameter is renamed as a prediction, no uniqueness result from the authors is invoked to rule out alternatives, and no known result is repackaged. Score 2 reflects only the presence of minor, non-load-bearing self-citations.

Assumptions & free parameters 0 free parameters · 5 assumptions · 0 invented entities

The main theorem rests on the non-splitting hypothesis and on several deep external results: Shusterman's orbit coincidence theorem, EVW16's stabilization element, and Davis-Schlank's Hilbert polynomial theorem. The authors introduce no new physical entities; the category FI(c) and the ordered Koszul complex are mathematical definitions rather than empirical postulates. No free parameters are fitted to data; the constants alpha, beta, N, N_0, N_c, A, B, and U are existential outputs of the cited theorems.

assumptions (5)
  • domain assumption (G,c) satisfies the non-splitting property: c generates G and c intersect H is either empty or a conjugacy class of H for all subgroups H.
    This is a hypothesis of Theorem 1.1 and is used throughout Sections 7, 8, and 9, for example in Corollary 7.6 and Lemma 7.8.
  • domain assumption Shusterman's Theorem 7.5: for a connected finite quandle X, PBr_n orbits and Br_n orbits of X^n coincide for all n at least N_X.
    Used to prove Corollary 7.6, which identifies pi_0(OHur) with pi_0(Hur) for n larger than a constant; this underpins Corollary 7.7 and the subsequent identifications of the ordered Koszul complex.
  • domain assumption EVW16 Lemma 3.5 (restated as Lemma 7.8): existence of N, N_0, and a central element U in H_0(Hur^c_G,N) such that multiplication by U is an isomorphism for n at least N_0, assuming |G| is a unit in the coefficient field.
    Provides the stabilization element rU used in Notation 7.9 and throughout Sections 7, 8, and 9 for the mapping cones and double complex.
  • domain assumption Davis-Schlank Proposition 3.36 (restated as Theorem 9.2): for a finitely generated left H_0(Hur^c_G;K)-module M, the dimension of M_n is constant for n sufficiently large.
    Used in Theorem 9.4 to conclude that the cohomology modules M_n = H^i(Hur^c_{G,n}; V_n(lambda)) stabilize once they are shown to be finitely generated.
  • domain assumption MPPRW Theorem 2.2 provides the proof template for Proposition 9.1; the paper says 'the proof is the same as that of Miller-Patzt-Petersen-Randal-Williams' and then gives an induction sketch.
    The core stability result is delegated to an unpublished preprint with overlapping authorship; the current paper does not provide a fully self-contained proof of this step.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Representation stability for ordered Hurwitz spaces." pith.science (2026). https://pith.science/paper/YKN2EKT3

@misc{pith2026250905516,
  author       = {Pith},
  title        = {Pith review of: Representation stability for ordered Hurwitz spaces},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/YKN2EKT3}},
  note         = {Machine review of arXiv:2509.05516}
}
read the original abstract

In this paper, we study the topology of ordered Hurwitz space. These are moduli spaces of branched covers with a choice of ordering on the branched points. Answering a question of Ellenberg, we prove that the homology of ordered Hurwitz spaces exhibit representation stability.

Figures

Figures reproduced from arXiv: 2509.05516 by the authors.

Figure 1
Figure 1. A point in OConfta,b,cu . Given a bijection of finite sets h: S Ñ T, we have an induced map h˚ : OConfS Ñ OConfT by precomposing with h ´1 , h˚ : OConfS ÝÑ OConfT pλ, ξq ÞÝÑ pλ, ξ ˝ h ´1 q. See [PITH_FULL_IMAGE:figures/full_fig_p006_1.png] view at source ↗
Figure 2
Figure 2. The action of a bijection h: S Ñ T. Definition 3.2. Let Conf be the N-graded space with Conf n “ OConfn{Σn for all n ě 0. We view an element of Confn as a length parameter λ and an n-element subset of p0, λq ˆ p0, 1q Ď R 2 , as in [PITH_FULL_IMAGE:figures/full_fig_p006_2.png] view at source ↗
Figure 3
Figure 3. A point in Conf3. The space OConf is a monoid object in TopFB, with the unit given by p0, ∅q. The product is defined by the formula OConfS0 ˆ OConfS1 ÝÑ OConfS0\S1 pλ0, ξ0q ¨ pλ1, ξ1q :“ pλ0 ` λ1, ξq where ξpsq “ # ξ0psq for s P S0, ξ1psq ` pλ0, 0q for s P S1. See [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figures from the paper (18 more)
Figure 4
Figure 4. Figure 4: The product pλ0, ξ0q ¨ pλ1, ξ1q is defined by concatenation of configurations. Definition 3.4. Let G be a finite group and c Ď G be a conjugation-invariant subset. Let OHurc G denote the FB-space whose value OHurc G,S on a finite set S has underlying set the set of tup…
Figure 5
Figure 5. Figure 5: An element of OHurc G,tr,s,tu . Each of the (unbased homotopy class of) loops ci corresponds to a conjugacy class of G contained in c. The subset Ů , and its image the basepoint of BG, are shown in blue. The space OHurc G,S is topologized as in Ellenberg–Venkatesh–West…
Figure 6
Figure 6. Figure 6: The action of an Artin generator of Brn on c n from the perspective of configuration mapping spaces. Compare to Formula (1). The object OHurc G P TopFB has the structure of a monoid object in TopFB, where pp0, ∅q, f0q is the unit, and the product is given by the formul…
Figure 7
Figure 7. Figure 7: The point ipwq “ ``1, ` 1 2 , 1 2 ˘˘ , fw ˘ P Hurc G,1 . Given v “ pv0, . . . , vpq P c p`1 , let ipvq P Hurc G,p`1 denote the element ipvq :“ ipv0q ¨ ipv1q ¨ . . . ¨ ipvpq as shown in [PITH_FULL_IMAGE:figures/full_fig_p009_7.png]
Figure 8
Figure 8. Figure 8: The element ipvq P Hurc G,3 for v “ pv0, v1, v2q. Given an object S P FB and an element s P S, let ξs : tsu Ñ p0, 8q ˆ p0, 1q denote the map sending s to ` 1 2 , 1 2 ˘ . Let ipw, sq P OHurc Gptsuq denote the element pp1, ξsq, fwq shown in [PITH_FULL_IMAGE:figures/full…
Figure 9
Figure 9. Figure 9: The element ipw, sq “ pp1, ξsq, fwq P OHurc Gptsuq . 1 0 BG v0 0 1 2 3 v1 v2 v0 v1 v2 α(0) α(1) α(2) [PITH_FULL_IMAGE:figures/full_fig_p010_9.png]
Figure 10
Figure 10. Figure 10: The element ipv, αq P OHurc G,impαq for v “ pv0, v1, v2q. 4. Variants of the semi-simplicial category In this section, we first recall a topological version of the semi-simplicial category introduced by Randal-Williams [RW24, Section 2] to construct resolutions of mod…
Figure 11
Figure 11. Figure 11: Morphisms in Upr0s,r2sq and Upr2s,r5sq, and their composite. For example, [PITH_FULL_IMAGE:figures/full_fig_p011_11.png]
Figure 12
Figure 12. Figure 12: Two morphisms in the path component associated to the monotone injection ι: r2s ÝÑ r5s 0 ÞÝÑ 1 1 ÞÝÑ 3 2 ÞÝÑ 4 Observe that the collection of such morphisms (for all q, p, and ι) is closed under composition. Definition 4.4. Let ∆r inj Ď U be the subcategory of U with …
Figure 13
Figure 13. Figure 13: A morphism associated to the face map d2 : r4s Ñ r5s. The category ∆r inj is a topological version of ∆inj. The functor ∆r inj Ñ ∆inj is a homotopy equivalence (see Krannich [Kra19, Lemma 2.11] and Randal-Williams [RW24, Page 3]), that is, the path components of ∆r in…
Figure 14
Figure 14. Figure 14: A morphism in Ucpw, vq where v “ pv0, v1, v2q and w “ pv0v1v ´1 0 q. Definition 4.6. Let w P c q`1 and v P c p`1 . There is a forgetful map Ucpw, vq Ñ Uprqs,rpsq. Define ∆r inj,cpw, vq Ď Ucpw, vq to be the pullback of the diagram of spaces ∆r inj,cpw, vq Ucpw, vq ∆r i…
Figure 15
Figure 15. Figure 15: A morphism in ∆r inj,cpw, vq where v is pv0, v1, v2, v3, v4, v5q and w is pv1, v3, v4q. We now define a Hurwitz analog of ∆inj. Definition 4.7. Define a category ∆inj,c as follows. The objects are the objects of ∆r inj,c. For w P c q`1 and v P c p`1 , the morphisms ∆i…
Figure 16
Figure 16. Figure 16: Two perspectives on (the path-homotopy class of) a Moore path γ with Moore parameter T lifting our sample injective map f : r2s Ñ r5s. The righthand image shows the motion of the configuration during the reverse path γ as the particles in positions 0, 1, 2 move to pos…
Figure 17
Figure 17. Figure 17: Our choice of basepoint and distinguished generators of the fundamental group of D5. The generators for D2 Ď D5 are bolded. distinguished generators in G “ π1pBG, ˚q as determined by µp0q P Hurc G,p`1 . Similarly, the tuple w encodes the images of the distinguished ge…
Figure 18
Figure 18. Figure 18: shows the map induced on the fundamental group of Dp in the case of our specific example. Observe that because the particles k “ 1, 2, . . . , q`1 only cross in front of other particles—the side closer to the basepoint—the braid γ maps the k-th distinguished generator…
Figure 20
Figure 20. Figure 20: An element pb, γq of RppMqpnq. 1 00 1 2 3 a 1 00 1 2 1 00 1 2 3 a 1 00 1 2 1 00 1 2 3 [PITH_FULL_IMAGE:figures/full_fig_p017_20.png]
Figure 21
Figure 21. Figure 21: An element pa, µq P ∆r injprqs,rpsq and its action on the element pb, γq P RppMqpnq of [PITH_FULL_IMAGE:figures/full_fig_p017_21.png]
Figure 22
Figure 22. Figure 22: For g P ∆inj,cpw, vq, define a braid β from σ p`1 to σ p`1 such that (read from bottom to top) the strands originating in positions 1, 2, . . . , q ` 1 pass in front of the complementary p ´ q strands, do not cross one another, and end at positions gprqsq. The complem…

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

46 extracted references · 37 canonical work pages

  1. [1]

    write newline

    " write newline "" before.all 'output.state := FUNCTION fin.entry add.period write newline FUNCTION new.block output.state before.all = 'skip after.block 'output.state := if FUNCTION new.sentence output.state after.block = 'skip output.state before.all = 'skip after.sentence 'output.state := if if FUNCTION not #0 #1 if FUNCTION and 'skip pop #0 if FUNCTIO...

  2. [2]

    Monoidal functors, species and Hopf algebras , volume 29

    Marcelo Aguiar and Swapneel Arvind Mahajan. Monoidal functors, species and Hopf algebras , volume 29. Citeseer, 2010

  3. [3]

    Deloopings of H urwitz spaces

    Andrea Bianchi. Deloopings of H urwitz spaces. Compos. Math. , 160(7):1651--1714, 2024

  4. [4]

    Polynomial stability of the homology of H urwitz spaces

    Andrea Bianchi and Jeremy Miller. Polynomial stability of the homology of H urwitz spaces. Math. Ann. , 391(3):4117--4144, 2025

  5. [5]

    FI -modules and stability for representations of symmetric groups

    Thomas Church, Jordan S Ellenberg, and Benson Farb. FI -modules and stability for representations of symmetric groups. Duke Mathematical Journal , 164(9), 2015

  6. [6]

    Representation theory and homological stability

    Thomas Church and Benson Farb. Representation theory and homological stability. Advances in Mathematics , 245:250--314, 2013

  7. [7]

    The braid group and the arc complex

    Chiara Damiolini. The braid group and the arc complex. Master's thesis, Universit \` a degli Studi di Milano and Universiteit Leiden, 2013. https://bfabef54-df58-4892-8175-96910b5c8570.filesusr.com/ugd/3e9a99\_202741101276496ebefce677e6c20214.pdf

  8. [8]

    On closed categories of functors

    Brian Day. On closed categories of functors. In Reports of the M idwest C ategory S eminar, IV , volume Vol. 137 of Lecture Notes in Math. , pages 1--38. Springer, Berlin-New York, 1970

Show all 46 references
  1. [9]

    On closed categories of functors

    Brian Day. On closed categories of functors. II . In Category S eminar ( P roc. S em., S ydney, 1972/1973) , volume Vol. 420 of Lecture Notes in Math. , pages 20--54. Springer, Berlin-New York, 1974

  2. [10]

    Abstract algebra , volume 3

    David Steven Dummit and Richard M Foote. Abstract algebra , volume 3. Wiley Hoboken, 2004

  3. [11]

    Ariel Davis and Tomer M. Schlank. The H ilbert polynomial of quandles and colorings of random links. Preprint, arXiv:2304.08314 https://arxiv.org/abs/2304.08314

  4. [12]

    A primer on homotopy colimits

    Daniel Dugger. A primer on homotopy colimits. https://pages.uoregon.edu/ddugger/hocolim.pdf https://pages.uoregon.edu/ddugger/hocolim.pdf

  5. [13]

    Ellenberg and Aaron Landesman

    Jordan S. Ellenberg and Aaron Landesman. Homological stability for generalized H urwitz spaces and S elmer groups in quadratic twist families over function fields. Preprint, arXiv:2310.16286 https://arxiv.org/abs/2310.16286

  6. [14]

    Semisimplicial spaces

    Johannes Ebert and Oscar Randal-Williams. Semisimplicial spaces. Algebr. Geom. Topol. , 19(4):2099--2150, 2019

  7. [15]

    Averages of arithmetic functions over conductors of function fields

    Jordan Ellenberg and Mark Shusterman. Averages of arithmetic functions over conductors of function fields. In preparation

  8. [16]

    Ellenberg, TriThang Tran, and Craig Westerland

    Jordan S. Ellenberg, TriThang Tran, and Craig Westerland. Fox-- N euwirth-- F uks cells, quantum shuffle algebras, and M alle's conjecture for function fields. Preprint, arXiv:1701.04541 https://arxiv.org/abs/1701.04541

  9. [17]

    Ellenberg, Akshay Venkatesh, and Craig Westerland

    Jordan S. Ellenberg, Akshay Venkatesh, and Craig Westerland. Homological stability for H urwitz spaces and the C ohen-- L enstra conjecture over function fields, II , 1212.0923. Preprint, arXiv:1212.0923 https://arxiv.org/abs/1212.0923

  10. [18]

    Ellenberg, Akshay Venkatesh, and Craig Westerland

    Jordan S. Ellenberg, Akshay Venkatesh, and Craig Westerland. Homological stability for H urwitz spaces and the C ohen-- L enstra conjecture over function fields. Ann. of Math. (2) , 183(3):729--786, 2016

  11. [19]

    Representation theory: a first course , volume 129

    William Fulton and Joe Harris. Representation theory: a first course , volume 129. Springer Science & Business Media, 2013

  12. [20]

    Midwest R epresentation S tability R esearch M eeting P roblem S ession, 2019

    Benson Farb, Jeremy Miller, and Peter Patzt. Midwest R epresentation S tability R esearch M eeting P roblem S ession, 2019. https://math.ou.edu/ ppatzt/stability2019/MRSRM-2019-Proplem-session.pdf http://math.ou.edu/ ppatzt/stability2019/MRSRM-2019-Proplem-session.pdf

  13. [21]

    Galatius, A

    S. Galatius, A. Kupers, and O. Randal-Williams. Cellular E _k -algebras. Preprint, to appear in Ast\'erisque, arXiv:1805.07184 https://arxiv.org/abs/1805.07184

  14. [22]

    Homological stability for moduli spaces of high dimensional manifolds

    S ren Galatius and Oscar Randal-Williams. Homological stability for moduli spaces of high dimensional manifolds. i. Journal of the American Mathematical Society , 31(1):215--264, 2018

  15. [23]

    Hirschhorn

    Philip S. Hirschhorn. Model categories and their localizations , volume 99 of Mathematical Surveys and Monographs . American Mathematical Society, Providence, RI, 2003

  16. [24]

    Tethers and homology stability for surfaces

    Allen Hatcher and Karen Vogtmann. Tethers and homology stability for surfaces. Algebraic & Geometric Topology , 17(3):1871--1916, 2017

  17. [25]

    Alexander Kupers, Ezekiel Lemann, Cary Malkiewich, Jeremy Miller, and Robin J. Sroka. Scissors automorphism groups and their homology, 2024. Preprint, arXiv:2408.08081 https://arxiv.org/abs/2408.08081

  18. [26]

    Homological stability of topological moduli spaces

    Manuel Krannich. Homological stability of topological moduli spaces. Geom. Topol. , 23(5):2397--2474, 2019

  19. [27]

    An alternate computation of the stable homology of dihedral group hurwitz spaces, 2410.22222

    Aaron Landesman and Ishan Levy. An alternate computation of the stable homology of dihedral group hurwitz spaces, 2410.22222. Preprint, arXiv:2410.22222 https://arxiv.org/abs/2410.22222

  20. [28]

    The C ohen-- L enstra moments over function fields via the stable homology of non-splitting H urwitz spaces

    Aaron Landesman and Ishan Levy. The C ohen-- L enstra moments over function fields via the stable homology of non-splitting H urwitz spaces. Preprint, arXiv:2410.22210 https://arxiv.org/abs/2410.22210

  21. [29]

    Homological stability for H urwitz spaces and applications

    Aaron Landesman and Ishan Levy. Homological stability for H urwitz spaces and applications. Preprint, arXiv:2503.03861 https://arxiv.org/abs/2503.03861

  22. [30]

    The stable homology of H urwitz spaces and applications

    Aaron Landesman and Ishan Levy. The stable homology of H urwitz spaces and applications. In preparation

  23. [31]

    Symmetric functions and H all polynomials

    Ian Grant Macdonald. Symmetric functions and H all polynomials . Oxford university press, 1998

  24. [32]

    The geometry of iterated loop spaces , volume 271

    J Peter May. The geometry of iterated loop spaces , volume 271. Springer, 2006

  25. [33]

    More concise algebraic topology: localization, completion, and model categories

    J Peter May and Kate Ponto. More concise algebraic topology: localization, completion, and model categories . University of Chicago Press, 2011

  26. [34]

    Representation stability, secondary stability, and polynomial functors

    Jeremy Miller, Peter Patzt, and Dan Petersen. Representation stability, secondary stability, and polynomial functors. Preprint, arxiv:1910.05574 https://arxiv.org/abs/1910.05574

  27. [35]

    Uniform twisted homological stability

    Jeremy Miller, Peter Patzt, Dan Petersen, and Oscar Randal-Williams. Uniform twisted homological stability. Preprint, arXiv:2402.00354 https://arxiv.org/abs/2402.00354

  28. [36]

    Central stability homology

    Peter Patzt. Central stability homology. Math. Z. , 295(3-4):877--916, 2020

  29. [37]

    Andrew Putman and Steven V. Sam. Representation stability and finite linear groups. Duke Math. J. , 166(13):2521--2598, 2017

  30. [38]

    A new approach to twisted homological stability with applications to congruence subgroups

    Andrew Putman. A new approach to twisted homological stability with applications to congruence subgroups. J. Topol. , 16(4):1315--1388, 2023

  31. [39]

    Homotopical algebra , volume 43

    Daniel G Quillen. Homotopical algebra , volume 43. Springer, 2006

  32. [40]

    Generalized representation stability and FI_d -modules

    Eric Ramos. Generalized representation stability and FI_d -modules. Proceedings of the American Mathematical Society , 145(11):4647--4660, 2017

  33. [41]

    Homology of H urwitz spaces and the C ohen- L enstra heuristic for function fields [after E llenberg, V enkatesh, and W esterland]

    Oscar Randal-Williams. Homology of H urwitz spaces and the C ohen- L enstra heuristic for function fields [after E llenberg, V enkatesh, and W esterland]. Ast\' e risque , 422(Exp. No. 1164):469--497, 2020

  34. [42]

    Classical homological stability from the point of view of cells

    Oscar Randal-Williams. Classical homological stability from the point of view of cells. Algebr. Geom. Topol. , 24(3):1691--1712, 2024

  35. [43]

    Homological stability for automorphism groups

    Oscar Randal-Williams and Nathalie Wahl. Homological stability for automorphism groups. Adv. Math. , 318:534--626, 2017

  36. [44]

    The tamely ramified geometric quantitative minimal ramification problem

    Mark Shusterman. The tamely ramified geometric quantitative minimal ramification problem. Compos. Math. , 160(1):21--51, 2024

  37. [45]

    Introduction to twisted commutative algebras

    Steven V Sam and Andrew Snowden. Introduction to twisted commutative algebras. Preprint, arXiv:1209.5122 https://arxiv.org/abs/1209.5122

  38. [46]

    A practical view of W : A guide to working with W eyl group representations, with special emphasis on branching rules

    John R Stembridge. A practical view of W : A guide to working with W eyl group representations, with special emphasis on branching rules. In Atlas of Lie Groups AIM Workshop IV , pages 10--14, 2006

Pith tools

Reviewed August 5, 2026 · model on record in the stance chip above.