Postulation of schemes of length at most 4 on surfaces

E. Ballico; S. Canino

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arXiv · 2511.22946

Postulation of schemes of length at most 4 on surfaces

E. Ballico·S. Canino

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Abstract

In this paper we address the postulation problem of zero-dimensional schemes on a surface of length at most 4. We prove some general results and then we focus on the case of P2, P1xP1 and Hirzebruch surfarces. In particular, we prove that except for few well-known exceptions, a general union of schemes of length at most 4 has always good postulation in P2 and in P1xP1.

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E. Ballico, S. Canino. 2025-11-28. Postulation of schemes of length at most 4 on surfaces. https://arxiv.org/abs/2511.22946

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