Morphism spaces on low degree hypersurfaces

Abstract

For $r>2$, we study the moduli space parameterising fixed degree morphisms ${\mathbb{P}}^r\to X$ where $X$ is a smooth hypersurface of low degree. More precisely, we prove the following result: let $n\ge 2,e\ge 1$ and $X\subset {\mathbb{P}}^{n-1}$ a smooth degree $d\ge 2$ hypersurface over an algebraically closed field of characteristic zero or greater than $d$, then ${\mathrm{Mor}}_e({\mathbb{P}}^r,X)$ is irreducible of the expected dimension if \[ n> 2^d(d-1)\binom{de+r-1}{r-1}. \] Our result extends the result of Browning-Yamagishi for $r=2$ via multiblock Weyl differencing.

arXiv comment19 pages