## Rocky Mountain Journal of Mathematics

### Psi-class intersections on Hassett spaces for genus 0 with all weights $\frac {1}{2}$

Nand Sharma

#### Abstract

Hassett spaces are moduli spaces of weighted stable pointed curves. We consider such spaces of curves of genus $0$ with weights all $\frac {1}{2}$. These spaces are interesting, since they are isomorphic to $\overline{M}_{0,n}$ but have different universal families and different intersection theory. We develop a closed formula for intersections of $\psi$-classes on such spaces. In our main result, we encode the formula for top intersections in a generating function obtained by applying a differential operator to the Witten potential.

#### Article information

Source
Rocky Mountain J. Math., Volume 49, Number 7 (2019), 2297-2324.

Dates
First available in Project Euclid: 8 December 2019

https://projecteuclid.org/euclid.rmjm/1575774139

Digital Object Identifier
doi:10.1216/RMJ-2019-49-7-2297

Mathematical Reviews number (MathSciNet)
MR4039971

Subjects
Primary: 14Q99: None of the above, but in this section

Keywords
$\psi$ classes Hassett spaces

#### Citation

Sharma, Nand. Psi-class intersections on Hassett spaces for genus 0 with all weights $\frac {1}{2}$. Rocky Mountain J. Math. 49 (2019), no. 7, 2297--2324. doi:10.1216/RMJ-2019-49-7-2297. https://projecteuclid.org/euclid.rmjm/1575774139

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