A-class conjecture for one frozen leg

Let Q=Q[a1,,an]Q=\mathbb{Q}[a_1,\dots,a_n]. For a stable rooted tree with one frozen leg, let Ag,n1R(Mg,n+1)QQA^1_{g,n}\in R^*({\overline{\mathcal{M}}}_{g,n+1})\otimes_{\mathbb{Q}}Q be the sum of the classes A(T)A(T) defined above, and let lvlΩg,n1{}^{lvl}\Omega^1_{g,n} be the corresponding degree-labeled stable tree expression. Here deg\deg denotes the degree in the variables a1,,ana_1,\dots,a_n. A-class conjecture. For g0g\geq 0 and n1n\geq 1, one has

deg(lvlΩg,n1Ag,n1)2g1.\deg\bigl({}^{lvl}\Omega^1_{g,n}-A^1_{g,n}\bigr)\leq 2g-1.

The conjecture is supported by computations for (g,n)=(1,2)(g,n)=(1,2) and (2,2)(2,2); it is proved in genus 00 and for n=0,1n=0,1 in the ranges stated in the supplied theorems, while the general case remains open.

Sources & referencesView supporting material

Primary source

Xavier Blot, Danilo Lewański, Paolo Rossi and Sergei Shadrin, “Stable tree expressions with Omega-classes and Double Ramification cycles”, arXiv:2403.05190 (2024).

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.