The Hausel partition-function conjecture for mixed Hodge polynomials of character varieties

Fix the number kk of marked points and the genus gg. For partitions μ1,,μk\mu_1,\ldots,\mu_k and the corresponding generic character variety Xg;Jμ1,,JμkX_{g;J_{\mu_1},\ldots,J_{\mu_k}}, let MHg,k\mathrm{MH}_{g,k} be the generating symmetric function of their mixed Hodge polynomials, and let Ωg,k\Omega_{g,k} be the partition function defined using modified Macdonald polynomials. Hausel's partition-function conjecture.

Ωg,k=Exp(MHg,k(q1)(t1)).\Omega_{g,k}=\operatorname{Exp}\left(-\frac{\mathrm{MH}_{g,k}}{(q-1)(t-1)}\right).

The source calls this the biggest open problem in the field and supplies no resolution; it relates all character varieties' mixed Hodge polynomials to a Macdonald-polynomial partition function.

Sources & referencesView supporting material

Primary source

Anton Mellit, “Cohomology rings of character varieties”, arXiv:2507.12454 (2025).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.