arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 2003.03966math.AC
收藏

同调移位理想

Homological shift ideals

Jürgen Herzog, Somayeh Moradi, Masoomeh Rahimbeigi, Guangjun Zhu

摘要:

对于单式理想$I$,我们考虑$I$的$i$次同调移位理想,记为$\text{HS}_i(I)$,即由$I$的$i$次多级移位生成的理想.研究了这类理想的一些代数性质。证明了对任意的单名理想$I$和任意的单名素理想$P$,对所有的$i$都有$\text{HS}_i(I(P))\subseteq \text{HS}_i(I)(P)$,其中$I(P)$是$I$的单名局部化.特别地,我们考虑了一些具有线性同调元的单项式理想族的同调移位理想。对任意$\textbf{c}$有界主Borel理想$I$和路图补图的边理想,证明了$\text{HS}_i(I)$对所有$i$都有线性映射.作为$\textbf{c}$ -有界主Borel理想的一个例子,考虑了Veronese型理想,并证明了这些理想的同调移位理想是多项式拟阵的.这意味着对于任何满足强交换性质的多拟阵理想,$\text{HS}_j(I)$对所有$j$都是多拟阵理想。对任意线性分辨率的边理想,刻画了理想$\text{HS}_j(I)$的特征,证明了理想$\text{HS}_1(I)$具有线性的边元.

英文摘要:

For a monomial ideal $I$, we consider the $i$th homological shift ideal of $I$, denoted by $\text{HS}_i(I)$, that is, the ideal generated by the $i$th multigraded shifts of $I$. Some algebraic properties of this ideal are studied. It is shown that for any monomial ideal $I$ and any monomial prime ideal $P$, $\text{HS}_i(I(P))\subseteq \text{HS}_i(I)(P)$ for all $i$, where $I(P)$ is the monomial localization of $I$. In particular, we consider the homological shift ideal of some families of monomial ideals with linear quotients. For any $\textbf{c}$-bounded principal Borel ideal $I$ and for the edge ideal of complement of any path graph, it is proved that $\text{HS}_i(I)$ has linear quotients for all $i$. As an example of $\textbf{c}$-bounded principal Borel ideals, Veronese type ideals are considered and it is shown that the homological shift ideal of these ideals are polymatroidal. This implies that for any polymatroidal ideal which satisfies the strong exchange property, $\text{HS}_j(I)$ is again a polymatroidal ideal for all $j$. Moreover, for any edge ideal with linear resolution, the ideal $\text{HS}_j(I)$ is characterized and it is shown that $\text{HS}_1(I)$ has linear quotients.

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。

↑