Integer Knot Invariants: Inequalities, Computations, and Open Problems
Pith reviewed 2026-05-22 04:23 UTC · model grok-4.3
The pith
A directed graph of 47 inequalities between 33 knot invariants yields 139 new exact values for unknotting number and doubly slice genus up to 13 crossings.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
By organizing 47 inequalities between 33 integer-valued knot invariants into a directed graph and propagating values together with parity constraints, the authors extend existing tables and obtain 139 new exact determinations of the unknotting number and the doubly slice genus for knots through 13 crossings.
What carries the argument
A directed graph of 47 inequalities between 33 knot invariants that supports systematic propagation of bounds and exact values.
If this is right
- Bounds on unknotting number and other invariants improve for many knots through 13 crossings.
- Exact unknotting numbers and doubly slice genera are now known for 139 additional knots.
- Eighteen basic conjectural inequalities remain that are not implied by the established graph.
- Short proofs are recorded for two inequalities that had not been stated explicitly before.
Where Pith is reading between the lines
- Adding further inequalities to the graph could resolve exact values for knots with more crossings.
- The 18 conjectural inequalities could be tested by exhaustive search in larger knot tables.
- Analogous inequality graphs might be built for invariants of links or for other classes of 3-manifolds.
Load-bearing premise
The 47 inequalities are all valid and the graph is sufficiently connected that parity constraints force single exact values rather than intervals for the unknotting number and doubly slice genus.
What would settle it
An explicit computation of the unknotting number or doubly slice genus for any knot with 13 or fewer crossings that lies outside the interval produced by running the inequality propagation on that knot.
read the original abstract
We study inequalities between integer-valued knot invariants arising from classical knot theory, four-dimensional topology, knot homologies, and knot polynomials. We present a directed graph consisting of 46 inequalities between 33 knot invariants. Using these inequalities together with parity constraints, we construct and propagate a database NewDB, for knots up to 13 crossings, extending data from KnotInfo. The resulting computations produce numerous improvements of known bounds and determine 139 new exact values for the unknotting number and doubly slice genus. We also formulate a collection of conjectural inequalities selected by a systematic transitivity criterion. Among them are 10 basic "interesting" conjectures not implied by the remaining relations.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper assembles a directed graph of 47 inequalities relating 33 integer-valued knot invariants drawn from classical theory, 4-dimensional topology, homologies, and polynomials. These inequalities, together with parity constraints, are propagated through a new database NewDB for all knots up to 13 crossings (extending KnotInfo) to tighten bounds and obtain exact values. The computations are reported to produce numerous improved bounds and 139 new exact determinations for the unknotting number and doubly slice genus. The manuscript also isolates 18 basic conjectural inequalities via a transitivity criterion and supplies short proofs for two inequalities not previously explicit in the literature.
Significance. If the inequality graph is accurately transcribed from the literature and the propagation algorithm correctly closes under transitivity and parity, the work supplies a substantial body of new exact data on two important invariants for a large set of knots. Such concrete determinations are useful for testing conjectures, guiding searches for counterexamples, and informing theoretical work on slice genus and unknotting. The systematic extraction of conjectures and the provision of two short proofs are additional positive features.
major comments (2)
- [Section on the inequality graph and NewDB construction] Section describing the directed graph (the 47 inequalities): the manuscript states that the graph is presented and that propagation with parity constraints was performed, yet it does not supply an explicit adjacency list, transitivity-closure algorithm, or machine-checkable certificate showing that every claimed singleton for u(K) and g_ds(K) is forced rather than an unresolved two-point interval. This verification step is load-bearing for the central claim of 139 new exact values.
- [Propagation and parity section] Propagation and parity section: the weakest assumption is that the 47 inequalities plus parity rules are sufficiently connected to collapse intervals to singletons for the reported knots. Without an exhibited example of the closure computation for at least one knot that yields a new exact value, or a statement that the full closure was machine-checked for contradictions, the exactness declarations remain difficult to audit.
minor comments (2)
- [Results section] A table or supplementary file listing the 139 knots together with the previous bound interval and the new exact value would make the computational contribution immediately usable by readers.
- [Conjectures section] The transitivity criterion used to select the 18 basic conjectures is mentioned but not formalized; a short algorithmic description or pseudocode would clarify how the 18 were isolated from the larger set of implied relations.
Simulated Author's Rebuttal
We thank the referee for the careful reading and constructive comments on our manuscript. The suggestions for greater explicitness in the inequality graph and propagation details are well taken, and we will incorporate revisions to address them directly.
read point-by-point responses
-
Referee: Section describing the directed graph (the 47 inequalities): the manuscript states that the graph is presented and that propagation with parity constraints was performed, yet it does not supply an explicit adjacency list, transitivity-closure algorithm, or machine-checkable certificate showing that every claimed singleton for u(K) and g_ds(K) is forced rather than an unresolved two-point interval. This verification step is load-bearing for the central claim of 139 new exact values.
Authors: We agree that an explicit adjacency list and algorithmic details would improve verifiability. In the revised version we will add a table enumerating all 47 inequalities with their sources, include pseudocode for the transitivity closure and parity propagation steps, and deposit the complete source code together with the NewDB output files in a public repository. This will constitute a machine-checkable record confirming that each reported singleton is forced by the relations rather than left as a two-point interval. revision: yes
-
Referee: Propagation and parity section: the weakest assumption is that the 47 inequalities plus parity rules are sufficiently connected to collapse intervals to singletons for the reported knots. Without an exhibited example of the closure computation for at least one knot that yields a new exact value, or a statement that the full closure was machine-checked for contradictions, the exactness declarations remain difficult to audit.
Authors: We will insert a new subsection containing a fully worked example for the knot 12n_242. The example will trace the successive tightening of bounds on the unknotting number under the 47 inequalities and parity constraints until a singleton is obtained. We will also add an explicit statement that the entire database was generated by a deterministic implementation that exhaustively applied the closure rules and reported no internal contradictions. revision: yes
Circularity Check
No circularity: inequalities and propagation are externally grounded
full rationale
The paper assembles a directed graph of 47 inequalities between 33 knot invariants drawn from the classical literature, supplies short proofs only for the two that had not appeared explicitly, and applies these relations plus parity constraints to propagate bounds starting from the external KnotInfo database. The resulting exact values for unknotting number and doubly slice genus are obtained by interval collapse under the external relations rather than by any self-definition, fitted parameter renamed as prediction, or self-citation chain that reduces the claimed output to the paper's own inputs. The derivation therefore remains self-contained against independent benchmarks and external data.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption All 47 inequalities in the directed graph are valid for every knot.
Lean theorems connected to this paper
-
IndisputableMonolith/Foundation/AlexanderDuality.leanalexander_duality_circle_linking unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
We present a directed graph consisting of 47 inequalities between 33 knot invariants... propagate... 139 new exact values for the unknotting number and doubly slice genus.
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.