Hirokazu Nasu

activity

20162025

collaborators

5 papers

math.AG2025

Obstructions to deforming space curves lying on a del Pezzo surface

Hirokazu Nasu

We study the deformations of space curves $C \subset P^{4}$ , assuming that they are contained in a smooth complete intersection $S_{2, 2} \subset P^{4}$ , i.e., a smooth…

math.AG2019

Obstructions to deforming space curves lying on a smooth cubic surface

Hirokazu Nasu

In this paper, we study the deformations of curves in the projective 3-space $P^{3}$ (space curves), one of the most classically studied objects in algebraic geometry. We pro…

math.AG2019

Obstructions to deforming curves on an Enriques-Fano 3-fold

Hirokazu Nasu

We study the deformations of a curve $C$ on an Enriques-Fano $3$ -fold $X \subset P^{n}$ , assuming that $C$ is contained in a smooth hyperplane section $S \subset X$ , that is…

math.AG2018

Obstructions to deforming curves on a prime Fano 3-fold

Hirokazu Nasu

We prove that for every smooth prime Fano $3$ -fold $V$ , the Hilbert scheme $Hilb^{sc} V$ of smooth connected curves on $V$ contains a generically non-reduced irreduc…

math.AG2016

Obstructions to deforming curves on a 3-fold, III: Deformations of curves lying on a K3 surface

Hirokazu Nasu

We study the deformations of a smooth curve $C$ on a smooth projective threefold $V$ , assuming the presence of a smooth surface $S$ satisfying $C \subset S \subset V$ . Generalizing…