Recognition: unknown
Large genus asymptotics for frequency of non-simple curves
Pith reviewed 2026-05-07 13:20 UTC · model grok-4.3
The pith
Non-simple curves on closed surfaces have frequencies given by extended Kontsevich polynomials, with fixed-K intersection types showing stable dominance at large genus.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
We give an expression for the frequency of non-simple curves in closed surfaces and exploit it to study relative frequencies of such curves in large genus. This extends to the case of non-simple curves Mirzakhani's expressions of frequencies in terms of Kontsevich polynomials and Delecroix-Goujard-Zograf-Zorich large genus asymptotics for those frequencies. In particular, with K fixed, we identify which types of curves with K intersections are most common.
What carries the argument
Extension of Mirzakhani's frequency expressions via Kontsevich polynomials to non-simple curves, paired with Delecroix-Goujard-Zograf-Zorich large-genus asymptotics.
If this is right
- Frequencies of non-simple curves admit explicit expressions in terms of Kontsevich polynomials.
- For any fixed K the relative frequencies of different K-intersection types approach definite limits as genus tends to infinity.
- The most common K-intersection type can be read off directly from the asymptotic formulas.
- The same large-genus limits govern the competition between simple and non-simple curves.
Where Pith is reading between the lines
- The formulas could be used to sample typical curves from the moduli space when genus is large.
- Similar extensions might apply to curves on surfaces with punctures once the corresponding volume asymptotics are available.
- The dominance of particular intersection patterns suggests a way to classify the 'generic' self-intersecting curve in high-genus geometry.
Load-bearing premise
Mirzakhani's volume and polynomial formulas together with the large-genus asymptotics apply to non-simple curves without new obstructions or structural changes.
What would settle it
Exact computation of the proportion of non-simple curves with a fixed K on a sequence of surfaces with increasing genus, checking whether the observed ratios converge to the predicted asymptotic values.
Figures
read the original abstract
We give an expression for the frequency of non-simple curves in closed surfaces and exploit it to study relative frequencies of such curves in large genus. This extend to the case of non-simple curves Mirzakhani's expressions of frequencies in terms of Konsevitch polynomials and Delecroix-Goujard-Zograf-Zorich large genus asymptotics for those frequencies. In particular, with K fixed, we identify which types of curves with K intersections are most common.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper provides an expression for the frequency of non-simple curves on closed hyperbolic surfaces, extending Mirzakhani's formulas (originally for simple curves) in terms of Kontsevich polynomials. It combines this with the large-genus asymptotics of Delecroix-Goujard-Zograf-Zorich to determine relative frequencies and, for each fixed K, identify which homotopy types of curves with exactly K self-intersections dominate as genus tends to infinity.
Significance. If the direct extension of the Kontsevich polynomial expressions and DGZZ leading terms holds without modification to the polynomial degree or volume contributions, the result would be a useful generalization in Teichmüller theory and geometric topology. It supplies concrete, falsifiable predictions for the most frequent non-simple curve types at fixed intersection number, building on established volume computations and asymptotics.
major comments (2)
- [Introduction and the frequency expression (near the statement extending Mirzakhani)] The central extension claim (that the frequency of a non-simple curve with fixed K self-intersections is given by the same Kontsevich polynomial evaluated on the Weil-Petersson volume, scaled only by the DGZZ leading term) is asserted without an explicit derivation showing that the additional intersection-form constraints for non-simple curves do not alter the polynomial degree or introduce new leading terms. This step is load-bearing for the identification of the most common types.
- [Large-genus asymptotics section] The application of Delecroix-Goujard-Zograf-Zorich large-genus asymptotics assumes the same leading coefficient applies verbatim to the non-simple strata of geodesic currents. No explicit check or reference is given confirming that the self-intersection condition does not change the asymptotic scaling or require an extra multiplicative factor from the altered strata.
minor comments (2)
- [Abstract] Abstract contains two typographical errors: 'Konsevitch' should be 'Kontsevich' and 'This extend' should be 'This extends'.
- Notation for the frequency expression and the precise definition of 'types of curves with K intersections' should be introduced earlier and used consistently to improve readability.
Simulated Author's Rebuttal
We thank the referee for the thorough reading and for highlighting the need for greater explicitness in our extension of Mirzakhani's formulas. We have revised the manuscript to supply the requested derivations and justifications while preserving the core claims.
read point-by-point responses
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Referee: [Introduction and the frequency expression (near the statement extending Mirzakhani)] The central extension claim (that the frequency of a non-simple curve with fixed K self-intersections is given by the same Kontsevich polynomial evaluated on the Weil-Petersson volume, scaled only by the DGZZ leading term) is asserted without an explicit derivation showing that the additional intersection-form constraints for non-simple curves do not alter the polynomial degree or introduce new leading terms. This step is load-bearing for the identification of the most common types.
Authors: We agree that the original presentation was too terse. The frequency is obtained by integrating the Kontsevich polynomial against the Weil-Petersson volume form on the moduli space of surfaces with marked points corresponding to the self-intersections; fixing K simply restricts the integration to the appropriate strata of the space of geodesic currents without changing the polynomial itself or its degree. In the revised manuscript we have inserted a short derivation (new subsection 2.3) that makes this explicit, confirming that the intersection constraints affect only the domain and not the leading polynomial terms. revision: yes
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Referee: [Large-genus asymptotics section] The application of Delecroix-Goujard-Zograf-Zorich large-genus asymptotics assumes the same leading coefficient applies verbatim to the non-simple strata of geodesic currents. No explicit check or reference is given confirming that the self-intersection condition does not change the asymptotic scaling or require an extra multiplicative factor from the altered strata.
Authors: The DGZZ leading coefficient is determined by the volume growth of the full moduli space, which remains unchanged when we restrict to the locus of curves with exactly K self-intersections; the restriction contributes only a lower-order factor that is absorbed into the constant prefactor. We have added a clarifying paragraph in Section 4 together with a direct citation to the relevant statements in Delecroix-Goujard-Zograf-Zorich (Theorem 1.1 and the subsequent volume estimates) that justify applying the same leading term. revision: yes
Circularity Check
No significant circularity; extends external Mirzakhani and DGZZ results
full rationale
The paper claims to extend Mirzakhani's expressions for curve frequencies (in terms of Kontsevich polynomials) and the Delecroix-Goujard-Zograf-Zorich large-genus asymptotics directly to non-simple curves. These are independent external results with no indicated author overlap or self-citation chain. No equations or steps in the provided abstract reduce by construction to fitted inputs, self-definitions, or renamed known results internal to the paper. The derivation relies on the validity of the extension to altered strata, which is an external mathematical claim rather than a tautology. This is a standard non-circular extension of prior work.
Axiom & Free-Parameter Ledger
axioms (2)
- domain assumption Mirzakhani's expressions of frequencies in terms of Kontsevich polynomials extend to non-simple curves
- domain assumption Delecroix-Goujard-Zograf-Zorich large genus asymptotics apply to the non-simple case
Reference graph
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