k-leaky double Hurwitz descendants
Forum of Mathematics, Sigma, Tome 13 (2025) no. 1, p. e60

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We define a new class of enumerative invariants called k-leaky double Hurwitz descendants, generalizing both descendant integrals of double ramification cycles and the k-leaky double Hurwitz numbers introduced in [CMR25]. These numbers are defined as intersection numbers of the logarithmic DR cycle against $\psi $-classes and logarithmic classes coming from piecewise polynomials encoding fixed branch point conditions. We give a tropical graph sum formula for these new invariants, allowing us to show their piecewise polynomiality in any genus. Investigating the piecewise polynomial structure further (and restricting to genus zero for this purpose), we also show a wall-crossing formula. We also prove that in genus zero the invariants are always nonnegative and give a complete classification of the cases where they vanish.
Cavalieri, Renzo; Markwig, Hannah; Schmitt, Johannes. k-leaky double Hurwitz descendants. Forum of Mathematics, Sigma, Tome 13 (2025) no. 1, p. e60. doi: 10.1017/fms.2025.26
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[ACFW13] Abramovich, D., Cadman, C., Fantechi, B. and Wise, J., ‘Expanded degenerations and pairs’, Comm. Algebra 41(6) (2013), 2346–2386. Google Scholar | DOI

[Bar19] Barrott, L. J., ‘Logarithmic Chow theory’, Preprint, 2019, . Google Scholar | arXiv

[BR21] Buryak, A. and Rossi, P., ‘Quadratic double ramification integrals and the noncommutative KdV hierarchy’, Bull. Lond. Math. Soc. 53(3) (2021), 843–854. Google Scholar | DOI

[BR24] Buryak, A. and Rossi, P., ‘Counting meromorphic differentials on ’, Lett. Math. Phys. 114(4) (2024), Paper No. 97, 27. Google Scholar | DOI

[BSSZ15] Buryak, A., Shadrin, S., Spitz, L. and Zvonkine, D., ‘Integrals of -classes over double ramification cycles’, Amer. J. Math. 137(3) (2015), 699–737. Google Scholar | DOI

[Bur15] Buryak, A., ‘Double ramification cycles and integrable hierarchies’, Comm. Math. Phys. 336(3) (2015), 1085–1107. Google Scholar | DOI

[CCUW20] Cavalieri, R., Chan, M., Ulirsch, M. and Wise, J., ‘A moduli stack of tropical curves’, Forum Math. Sigma 8 (2020), Paper No. e23, 93. Google Scholar | DOI

[CGH+22] Chen, D., Grushevsky, S., Holmes, D., Möller, M. and Schmitt, J., ‘A tale of two moduli spaces: logarithmic and multi-scale differentials’, Preprint, 2022, . Google Scholar | arXiv

[CH24] Chiodo, A. and Holmes, D., ‘Double ramification cycles within degeneracy loci via moduli of roots’, Preprint, 2024, . Google Scholar | arXiv

[CJM10] Cavalieri, R., Johnson, P. and Markwig, H., ‘Tropical Hurwitz numbers’, J. Algebr. Comb. 32(2) (2010), 241–265, . Google Scholar | arXiv | DOI

[CJM11] Cavalieri, R., Johnson, P. and Markwig, H., ‘Wall crossings for double Hurwitz numbers’, Adv. Math. 228(4) (2011), 1894–1937. Google Scholar

[CM14] Cavalieri, R. and Marcus, S., ‘Geometric perspective on piecewise polynomiality of double Hurwitz numbers’, Canad. Math. Bull. 57(4) (2014), 749–764. Google Scholar | DOI

[CMR25] Cavalieri, R., Markwig, H. and Ranganathan, D., ‘Pluricanonical cycles and tropical covers’, Trans. Amer. Math. Soc. 378(1) (2025), 117–158. Google Scholar

[CMS] Cavalieri, R., Markwig, H. and Schmitt, J., ‘One-part leaky covers’, in preparation. Google Scholar

[CP23] Chen, D. and Prado, M., ‘Counting differentials with fixed residues’, Preprint, 2023, . Google Scholar | arXiv

[CSS21] Costantini, M., Sauvaget, A. and Schmitt, J., ‘Integrals of -classes on twisted double ramification cycles and spaces of differentials’, Preprint, 2021, . Google Scholar | arXiv

[DSvZ21] Delecroix, V., Schmitt, J. and Van Zelm, J., ‘admcycles—a Sage package for calculations in the tautological ring of the moduli space of stable curves’, J. Softw. Algebra Geom. 11(1) (2021), 89–112. Google Scholar | DOI

[GJ92] Goulden, I. P. and Jackson, D. M., ‘The combinatorial relationship between trees, cacti and certain connection coefficients for the symmetric group’, European J. Combin. 13(5) (1992), 357–365. Google Scholar | DOI

[GJV05] Goulden, I., Jackson, D. and Vakil, R., ‘Towards the geometry of double Hurwitz numbers’, Adv. Math. 198(1) (2005), 43–92. Google Scholar | DOI

[GT22] Gendron, Q. and Tahar, G., ‘Isoresidual fibration and resonance arrangements’, Lett. Math. Phys. 112(2) (2022), Paper No. 33, 36. Google Scholar | DOI

[GV05] Graber, T. and Vakil, R., ‘Relative virtual localization and vanishing of tautological classes on moduli spaces of curves’, Duke Math. J. 130(1) (2005), 1–37. Google Scholar | DOI

[HMP+22] Holmes, D., Molcho, S., Pandharipande, R., Pixton, A. and Schmitt, J., ‘Logarithmic double ramification cycles’, Preprint, 2022, . Google Scholar | arXiv

[Hol19] Holmes, D., ‘Extending the double ramification cycle by resolving the Abel-Jacobi map’, J. Inst. Math. Jussieu (2019), https://doi.org/10.1017/S1474748019000252. Google Scholar

[HS21] Holmes, D. and Schmitt, J., ‘Infinitesimal structure of the pluricanonical double ramification locus’, Compos. Math. 157(10) (2021), 2280–2337. Google Scholar

[JPPZ17] Janda, F., Pandharipande, R., Pixton, A. and Zvonkine, D., ‘Double ramification cycles on the moduli spaces of curves’, Publ. Math. Inst. Hautes Études Sci. 125(1) (2017), 221–266. Google Scholar | DOI

[Li01] Li, J., ‘Stable morphisms to singular schemes and relative stable morphisms’, J. Differential Geom. 57(3) (2001), 509–578. Google Scholar | DOI

[Li02] Li, J., ‘A degeneration formula of GW-invariants’, J. Differential Geom. 60(2) (2002), 199–293. Google Scholar | DOI

[Mou00] Mount, J.Fast unimodular counting’, Combin. Probab. Comput. 9(3) (2000), 277–285. Google Scholar | DOI

[MPS23] Molcho, S., Pandharipande, R. and Schmitt, J., ‘The Hodge bundle, the universal 0-section, and the log Chow ring of the moduli space of curves’, Compos. Math. 159(2) (2023), 306–354. Google Scholar | DOI

[MW20] Marcus, S. and Wise, J., ‘Logarithmic compactification of the Abel-Jacobi section’, Proc. Lond. Math. Soc. (3) 121(5) (2020), 1207–1250. Google Scholar | DOI

[Oes19] Oesinghaus, J., ‘Quasisymmetric functions and the Chow ring of the stack of expanded pairs’, Res. Math. Sci. 6(1) (2019), Paper No. 5, 18. Google Scholar

[PRSS24] Pandharipande, R., Ranganathan, D., Schmitt, J. and Spelier, P., ‘Logarithmic tautological rings of the moduli spaces of curves’, 2024. Google Scholar

[PZ] Pixton, A. and Zagier, D., ‘On combinatorial properties of the explicit expression for double ramification cycles’, in preparation, see here for a preliminary version. Google Scholar

[Sau] Sauvaget, A., ‘Combinatorics of integrals on double ramification cycles’, in preparation. Google Scholar

[Sch03] Schrijver, A., Combinatorial Optimization. Polyhedra and Efficiency. Vol. A (Algorithms and Combinatorics) vol. 24A (Springer-Verlag, Berlin, 2003). Paths, flows, matchings, Chapters 1–38. Google Scholar

[Spe24] Spelier, P., ‘Polynomiality of the double ramification cycle’, Preprint, 2024, . Google Scholar | arXiv

[Spe25] Spelier, P., ‘Splitting formulas for logarithmic double ramification cycles’, 2025, to appear. Google Scholar

[SSV08] Shadrin, S., Shapiro, M. and Vainshtein, A., ‘Chamber behavior of double Hurwitz numbers in genus 0’, Adv. Math. 217(1) (2008), 79–96. Google Scholar | DOI

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