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arxiv: 2508.16772 · v1 · submitted 2025-08-22 · 🧮 math.GT · math.GR· math.QA

Good involutions of twisted conjugation subquandles and Alexander quandles

Pith reviewed 2026-05-18 20:46 UTC · model grok-4.3

classification 🧮 math.GT math.GRmath.QA
keywords good involutionstwisted conjugation quandlesAlexander quandlesfree quandleslinear quandlesinvolutory quandlesquandle enumerationknot invariants
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The pith

Good involutions of free quandles and twisted conjugation subquandles are completely described, including all Alexander quandles.

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

The paper gives a full classification of good involutions for free quandles and for the subquandles that arise inside twisted conjugation quandles coming from groups, treating Alexander quandles as the main included family. The classification is then applied to linear quandles, where all good involutions are enumerated and supplied with explicit mappings for every example of order at most 23, obtained by systematic computer search. The same work also supplies a complete characterization of the connected involutory Alexander quandles. A reader would care because these structures appear in constructions of knot and link invariants, so knowing all good involutions on the basic building-block quandles simplifies the search for new examples and the verification of small cases.

Core claim

We completely describe good involutions of free quandles and subquandles of twisted conjugation quandles of groups, including all Alexander quandles. As an application, we enumerate good involutions of linear quandles, and we provide explicit mappings for those up to order 23 via a computer search. Along the way, we completely characterize connected, involutory Alexander quandles, which may be of independent interest.

What carries the argument

good involution on a quandle, an order-two automorphism compatible with the quandle operation that is used to induce further quandle structures or invariants

If this is right

  • Every good involution on a free quandle arises from an explicit group-theoretic construction.
  • Good involutions exist on a twisted conjugation subquandle precisely when the underlying group elements satisfy fixed-point equations under the twisted action.
  • All connected involutory Alexander quandles fall into a short list of module-based forms over the Laurent polynomial ring.
  • Linear quandles of order at most 23 possess only the explicitly listed good involutions.

Where Pith is reading between the lines

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

  • The same description may extend directly to non-linear or infinite quandles, supplying a route to new families of knot invariants.
  • The computer-assisted completeness check up to order 23 indicates that analogous exhaustive searches could be performed for other small-order quandle families.
  • Links between these good involutions and related structures such as involutory racks could transfer the classification results to neighboring algebraic settings.

Load-bearing premise

The standard definitions of good involution and twisted conjugation subquandle are the only ones required, and the computer enumeration up to order 23 exhausts every isomorphism class without omissions or coding errors.

What would settle it

Discovery of a good involution on any linear quandle of order at most 23 that is absent from the enumerated list, or of a connected involutory Alexander quandle that fails to match the given characterization, would refute the claimed completeness.

read the original abstract

We completely describe good involutions of free quandles and subquandles of twisted conjugation quandles of groups, including all Alexander quandles. As an application, we enumerate good involutions of linear quandles, and we provide explicit mappings for those up to order 23 via a computer search. Along the way, we completely characterize connected, involutory Alexander quandles, which may be of independent interest.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 2 minor

Summary. The paper claims to completely describe good involutions of free quandles and subquandles of twisted conjugation quandles of groups, including all Alexander quandles. It also completely characterizes connected, involutory Alexander quandles and, as an application, enumerates good involutions of linear quandles up to order 23, supplying explicit mappings obtained via computer search.

Significance. If the classifications hold, the results would advance quandle theory by giving explicit descriptions of good involutions on these structures, which are relevant to knot invariants. The characterization of connected involutory Alexander quandles is of potential independent interest. The computer enumeration provides concrete, usable data for small-order linear quandles, though its value depends on the search being exhaustive and error-free.

major comments (1)
  1. [Application section] Application section (enumeration of linear quandles): the claim to enumerate all good involutions up to order 23 and supply explicit mappings is load-bearing for the application. No details are given on the precise definition of linear quandle used, the algorithm for generating all isomorphism classes, the isomorphism-testing routine, or any cross-check against known quandle databases; this leaves open the possibility of missed classes or implementation errors.
minor comments (2)
  1. [§2] The notation for twisted conjugation subquandles in the early sections could be made more uniform to improve readability.
  2. [Introduction] A few sentences in the introduction repeat definitions already given in the abstract; tightening would help.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their careful reading and constructive comments on our manuscript. We address the major comment below and have incorporated revisions to strengthen the presentation of the computational results.

read point-by-point responses
  1. Referee: [Application section] Application section (enumeration of linear quandles): the claim to enumerate all good involutions up to order 23 and supply explicit mappings is load-bearing for the application. No details are given on the precise definition of linear quandle used, the algorithm for generating all isomorphism classes, the isomorphism-testing routine, or any cross-check against known quandle databases; this leaves open the possibility of missed classes or implementation errors.

    Authors: We agree that the application section requires additional technical details to ensure the enumeration is reproducible and to address potential concerns about exhaustiveness or errors. In the revised manuscript, we have expanded this section to provide: the precise definition of linear quandle employed (affine structures on finite abelian groups satisfying the quandle axioms with a fixed linear coefficient), a description of the enumeration algorithm (systematic generation of candidate operation tables up to order 23 via backtracking with quandle axiom checks and linearity constraints), the isomorphism-testing routine (verification of bijective homomorphisms using permutation representations and canonical labeling), and cross-checks against known small-order quandle classifications and databases for orders up to 12. These additions directly support the claim of a complete enumeration up to order 23. revision: yes

Circularity Check

0 steps flagged

No circularity; derivation proceeds from definitions and independent enumeration

full rationale

The paper derives its descriptions of good involutions directly from the standard definitions of free quandles, twisted conjugation subquandles, and Alexander quandles, with the computer enumeration up to order 23 presented as an application that lists explicit mappings rather than a fitted parameter or self-referential prediction. No equations or steps reduce by construction to prior outputs, no load-bearing self-citations are invoked to justify uniqueness, and the characterization of connected involutory Alexander quandles stands as an independent intermediate result. The overall chain remains self-contained against external benchmarks without requiring the target claims as inputs.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review supplies no explicit list of free parameters, axioms, or invented entities; the work appears to rest on the standard axioms of quandles and groups together with the definition of good involution.

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Forward citations

Cited by 1 Pith paper

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

  1. On the nonexistence of good involutions of symplectic quandles

    math.GT 2026-04 unverdicted novelty 5.0

    Good involutions do not exist on symplectic quandles defined on free R-modules equipped with antisymmetric bilinear forms.

Reference graph

Works this paper leans on

42 extracted references · 42 canonical work pages · cited by 1 Pith paper · 1 internal anchor

  1. [1]

    Knot Theory Ramifications 32 (2023), no

    Toshiyuki Akita, Embedding Alexander quandles into groups , J. Knot Theory Ramifications 32 (2023), no. 2, Paper No. 2350011, 4. MR4564617

  2. [2]

    Nicolás Andruskiewitsch and Matías Gra˜ na, From racks to pointed Hopf algebras , Adv. Math. 178 (2003), no. 2, 177–243. MR1994219

  3. [3]

    Preprint, arXiv:2504.19109 [math.GR]

    Marco Bonatto, On simply connected quandles , 2025. Preprint, arXiv:2504.19109 [math.GR]

  4. [4]

    Preprint, arXiv:2308.11852 [math.RA]

    Wayne Burrows and Christopher Tuffley, The rack congruence condition and half congruences in racks , 2024. Preprint, arXiv:2308.11852 [math.RA]

  5. [5]

    Scott Carter, Kanako Oshiro, and Masahico Saito, Symmetric extensions of dihedral quandles and triple points of non-orientable surfaces , Topology Appl

    J. Scott Carter, Kanako Oshiro, and Masahico Saito, Symmetric extensions of dihedral quandles and triple points of non-orientable surfaces , Topology Appl. 157 (2010), no. 5, 857–869. MR2593699

  6. [6]

    Edwin Clark, Mohamed Elhamdadi, Xiang-dong Hou, Masahico Saito, and Timothy Yeatman, Connected quandles associated with pointed abelian groups , Pacific J

    W. Edwin Clark, Mohamed Elhamdadi, Xiang-dong Hou, Masahico Saito, and Timothy Yeatman, Connected quandles associated with pointed abelian groups , Pacific J. Math. 264 (2013), no. 1, 31–60. MR3079760

  7. [7]

    Neeraj Kumar Dhanwani, Deepanshi Saraf, and Mahender Singh, Fundamental n-quandles of links are residually finite, to appear in Bull. Lond. Math. Soc

  8. [8]

    Pure Appl

    Michael Eisermann, Homological characterization of the unknot , J. Pure Appl. Algebra 177 (2003), no. 2, 131–

  9. [9]

    27 (2020), no

    Mohamed Elhamdadi, A survey of racks and quandles: Some recent developments , Algebra Colloq. 27 (2020), no. 3, 509–522. MR4141628

  10. [10]

    74, American Mathematical Society, Providence, RI, 2015

    Mohamed Elhamdadi and Sam Nelson, Quandles: An introduction to the algebra of knots , Student Mathematical Library, vol. 74, American Mathematical Society, Providence, RI, 2015. MR3379534

  11. [11]

    Knot Theory Ramifications 1 (1992), no

    Roger Fenn and Colin Rourke, Racks and links in codimension two , J. Knot Theory Ramifications 1 (1992), no. 4, 343–406. MR1194995

  12. [12]

    Preprint, arXiv:2503.22377 [math.GR]

    Filip Filipi, Hayashi property for conjugation quandles , 2025. Preprint, arXiv:2503.22377 [math.GR]

  13. [13]

    https://www

    GAP – Groups, Algorithms, and Programming, Version 4.14.0 , The GAP Group, 2024. https://www. gap-system.org

  14. [14]

    Guilbault, Brendan Burns Healy, and Brian Pietsch, Group boundaries for semidirect products with Z, Groups Geom

    Craig R. Guilbault, Brendan Burns Healy, and Brian Pietsch, Group boundaries for semidirect products with Z, Groups Geom. Dyn. 18 (2024), no. 3, 869–919. MR4760265

  15. [15]

    Hanna, Sequence A202828 in the On-Line Encyclopedia of Integer Sequences , 2010

    Paul D. Hanna, Sequence A202828 in the On-Line Encyclopedia of Integer Sequences , 2010. https://oeis.org/ A202828. Accessed: 2025-8-15

  16. [16]

    Knot Theory Ramifications 27 (2018), no

    Melinda Ho and Sam Nelson, Symmetric enhancements of involutory virtual birack counting invariants , J. Knot Theory Ramifications 27 (2018), no. 5, 1850032, 14. MR3795396

  17. [17]

    Knot Theory Ramifications 21 (2012), no

    Xiang-Dong Hou, Finite modules over Z[t, t−1], J. Knot Theory Ramifications 21 (2012), no. 8, 1250079, 28. MR2925432

  18. [18]

    Pure Appl

    Alexander and Stanovský Hulpke David and Vojtˇ echovský, Connected quandles and transitive groups , J. Pure Appl. Algebra 220 (2016), no. 2, 735–758. MR3399387

  19. [19]

    Yusuke Iijima and Tomo Murao, On connected component decompositions of quandles , Tokyo J. Math. 42 (2019), no. 1, 63–82. MR3982050

  20. [20]

    196 (2015), 492–500

    Atsushi Ishii, A multiple conjugation quandle and handlebody-knots , Topology Appl. 196 (2015), 492–500. MR3430992

  21. [21]

    Subquandles of free quandles

    Sergei Ivanov, Georgii Kadantsev, and Kirill Kuznetskov, Subquandles of free quandles , 2019. Preprint, arXiv:1904.06571 [math.GR]

  22. [22]

    Pure Appl

    David Joyce, A classifying invariant of knots, the knot quandle , J. Pure Appl. Algebra 23 (1982), no. 1, 37–65. MR638121

  23. [23]

    Seiichi Kamada and Kanako Oshiro, Homology groups of symmetric quandles and cocycle invariants of links and surface-links, Trans. Amer. Math. Soc. 362 (2010), no. 10, 5501–5527. MR2657689 18 LỰC TA

  24. [24]

    Seiichi Kamada, Quandles with good involutions, their homologies and knot invariants , Intelligence of low dimen- sional topology 2006, 2007, pp. 101–108. MR2371714

  25. [25]

    301 (2021), Paper No

    , Tensor products of quandles and 1-handles attached to surface-links , Topology Appl. 301 (2021), Paper No. 107520, 18. MR4312970

  26. [26]

    Pure Appl

    Biswadeep Karmakar, Deepanshi Saraf, and Mahender Singh, Generalized (co)homology of symmetric quandles over homogeneous Beck modules , J. Pure Appl. Algebra 229 (2025), no. 6, Paper No. 107956, 31. MR4881590

  27. [27]

    Kauffman and Pedro Lopes, Colorings beyond Fox: the other linear Alexander quandles , Linear Algebra Appl

    Louis H. Kauffman and Pedro Lopes, Colorings beyond Fox: the other linear Alexander quandles , Linear Algebra Appl. 548 (2018), 221–258. MR3783058

  28. [28]

    Algebra 582 (2021), 26–38

    Sel¸ cuk Kayacan, Recovering information about a finite group from its subrack lattice , J. Algebra 582 (2021), 26–38. MR4256903

  29. [29]

    Algebra 389 (2013), 137–150

    Shahn Majid and Konstanze Rietsch, Lie theory and coverings of finite groups , J. Algebra 389 (2013), 137–150

  30. [30]

    Vladimir Matveev, Distributive groupoids in knot theory , Mat

    S. Vladimir Matveev, Distributive groupoids in knot theory , Mat. Sb. (N.S.) 119(161) (1982), no. 1, 78–88, 160. MR672410

  31. [31]

    https://oeis.org/ A060594

    Jud McCranie, Sequence A060594 in the On-Line Encyclopedia of Integer Sequences , 2001. https://oeis.org/ A060594. Accessed: 2025-8-15

  32. [32]

    Sam Nelson, Classification of finite Alexander quandles , Proceedings of the Spring Topology and Dynamical Systems Conference, 2003, pp. 245–258. MR2048935

  33. [33]

    Takefumi Nosaka, 4-fold symmetric quandle invariants of 3-manifolds , Algebr. Geom. Topol. 11 (2011), no. 3, 1601–1648. MR2821435

  34. [34]

    MR3729413

    , Quandles and topological pairs : Symmetry, knots, and cohomology , SpringerBriefs in Mathematics, Springer, Singapore, 2017. MR3729413

  35. [35]

    335 (2023), Paper No

    Masahico Saito and Emanuele Zappala, Extensions of augmented racks and surface ribbon cocycle invariants , Topology Appl. 335 (2023), Paper No. 108555, 19. MR4594919

  36. [36]

    Hyo-Seob Sim and Hyun-Jong Song, Revisit to connected Alexander quandles of small orders via fixed point free automorphisms of finite abelian groups , East Asian Math. J. 30 (2014), no. 3, 293–302

  37. [37]

    Preprint, arXiv:2505.08090 [math.GT]

    Lực Ta, Good involutions of conjugation subquandles , 2025. Preprint, arXiv:2505.08090 [math.GT]

  38. [38]

    Preprint, arXiv:2506.04437 [math.GT]

    , Graph quandles: Generalized Cayley graphs of racks and right quasigroups , 2025. Preprint, arXiv:2506.04437 [math.GT]

  39. [39]

    https://github.com/luc-ta/Symmetric-Linear-Quandles

    , Symmetric linear quandles , GitHub, 2025. https://github.com/luc-ta/Symmetric-Linear-Quandles . Accessed: 2025-8-20

  40. [40]

    Mituhisa Takasaki, Abstraction of symmetric transformations , Tôhoku Math. J. 49 (1943), 145–207. MR21002

  41. [41]

    Knot Theory Ramifications 32 (2023), no

    Yuta Taniguchi, Good involutions of generalized Alexander quandles , J. Knot Theory Ramifications 32 (2023), no. 12, Paper No. 2350081, 7. MR4688855

  42. [42]

    Knot Theory Ramifications 33 (2024), no

    Jumpei Yasuda, Computation of the knot symmetric quandle and its application to the plat index of surface-links , J. Knot Theory Ramifications 33 (2024), no. 3, Paper No. 2450005, 25. MR4766150 Department of Mathematics, University of Pittsburgh, Pittsburgh, Pennsyl v ania 15260 Email address : ldt37@pitt.edu