arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2005.12817math.AG
收藏

关于一般线性级数在稳定曲线上的秩

On the rank of general linear series on stable curves

Karl Christ

摘要:

本文研究了稳定曲线上特殊线丛的轨迹维数,并对固定的半稳定多自由度进行了研究。在全次数$d = g - 1$的情况下,我们刻画了有效轨迹何时给出θ因子。在度$g - 2$和$g$的情况下,我们证明了轨迹是空的或具有期望的维数。这导致在这些程度的半稳定性的一个新的特征。在其余的情况下,我们表明,特殊的轨迹有余维至少$2$。如果曲线的每一个不可约分量上的多重度都是非负的,我们证明了特殊轨迹包含一个期望维数的可约分量。

英文摘要:

We study the dimension of loci of special line bundles on stable curves and for a fixed semistable multidegree. In case of total degree $d = g - 1$, we characterize when the effective locus gives a Theta divisor. In case of degree $g - 2$ and $g$, we show that the locus is either empty or has the expected dimension. This leads to a new characterization of semistability in these degrees. In the remaining cases, we show that the special locus has codimension at least $2$. If the multidegree in addition is non-negative on each irreducible component of the curve, we show that the special locus contains an irrreducible component of expected dimension.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑