# Separators of Arithmetically Cohen-Macaulay fat points in P^1 x P^1

@article{Guardo2010SeparatorsOA, title={Separators of Arithmetically Cohen-Macaulay fat points in P^1 x P^1}, author={Elena Guardo and Adam Van Tuyl}, journal={arXiv: Commutative Algebra}, year={2010} }

Let Z be a set of fat points in P^1 x P^1 that is also arithmetically Cohen-Macaulay (ACM). We describe how to compute the degree of a separator of a fat point of multiplicity m for each point in the support of Z using only a numerical description of Z. Our formula extends the case of reduced points which was previously known.

## 3 Citations

### On the arithmetically Cohen-Macaulay property for sets of points in multiprojective spaces

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We study the arithmetically Cohen-Macaulay (ACM) property for finite sets of points in multiprojective spaces, especially $(\mathbb P^1)^n$. A combinatorial characterization, the $(\star)$-property,…

### Kaehler differentials for fat point schemes in P^1xP^1

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- 2016

Let $X$ be a set of $K$-rational points in $P^1 \times P^1$ over a field $K$ of characteristic zero, let $Y$ be a fat point scheme supported at $ X$, and let $R_Y$ be the bihomogeneus coordinate ring…

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