# Wall-crossings for Hassett descendant potentials

**Authors:** Vance Blankers, Renzo Cavalieri

arXiv: 1907.06277 · 2019-07-16

## TL;DR

This paper explores the intersection theory of Hassett spaces, deriving generating functions for $	ext{psi}$ class intersections from Gromov-Witten potentials, and extends these results to tautological cycle comparisons.

## Contribution

It provides a combinatorial framework linking Hassett space intersection theory to Gromov-Witten theory and introduces explicit variable transformations for these generating functions.

## Key findings

- Derived a generating function for Hassett space intersection numbers from Gromov-Witten potential.
- Explicit polynomial transformations for diagonal weights.
- Extended potential comparison to tautological cycle level using pinwheel cycle potential.

## Abstract

This paper solves the combinatorics relating the intersection theory of $\psi$-classes of Hassett spaces to that of $\overline{\mathcal{M}}_{g,n}$. A generating function for intersection numbers of $\psi$ classes on all Hassett spaces is obtained from the Gromov-Witten potential of a point via a non-invertible transformation of variables. When restricting to diagonal weights, the changes of variables are invertible and explicitly described as polynomial functions. Finally, the comparison of potentials is extended to the level of cycles: the pinwheel cycle potential, a generating function for tautological classes of rational tail type on $\overline{\mathcal{M}}_{g,n}$ is the right instrument to describe the pull-back to $\overline{\mathcal{M}}_{g,n}$ of all monomials of $\psi$ classes on Hassett spaces.

## Full text

_Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/1907.06277/full.md

## Figures

4 figures with captions in the complete paper: https://tomesphere.com/paper/1907.06277/full.md

## References

19 references — full list in the complete paper: https://tomesphere.com/paper/1907.06277/full.md

---
Source: https://tomesphere.com/paper/1907.06277