arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1408.2273math.RT
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SL3(k)的线丛上同调群的支撑簇

Support varieties of line bundle cohomology groups for SL3 (k)

William D. Hardesty

摘要:

令$G= SL_3(k)$,其中$k$是特征$p > 0$的字段,并且令$λ\in X(T)$是具有$G/B$上的相应线丛$\mathscr{L}(λ)$的任何权重。在本文中,我们计算支持品种的形式$H^i(λ):= H^i(G/B, \mathscr{L}(λ))$的所有模块的第一Frobenius核$G_1$。该计算涉及到Donkin给出的某些递归特征标公式,这些公式可用于计算线丛上同调群的特征标。在$λ$是$p$ -正则权重且对于某些$i$是$M=H^i(λ)\neq 0$的情况下,这些公式用于表明单位$ζ$的任何$p^{th}$根不是$M$的类属维数的根。为了处理的情况下,$λ$是不$p$ -定期,我们采用类似的技术所使用的Drupieski,中野和Parshall表明,模块$H^i(λ)$是不投射在$G_1$,只要它是非零和$λ$在于外面的斯坦伯格块。

英文摘要:

Let $G= SL_3(k)$ where $k$ is a field of characteristic $p > 0$ and let $λ\in X(T)$ be any weight with corresponding line bundle $\mathscr{L}(λ)$ on $G/B$. In this paper we compute the support varieties for all modules of the form $H^i(λ):= H^i(G/B, \mathscr{L}(λ))$ over the first Frobenius kernel $G_1$. The calculation involves certain recursive character formulas given by Donkin which can be used to compute the characters of the line bundle cohomology groups. In the case where $λ$ is a $p$-regular weight and $M=H^i(λ)\neq 0$ for some $i$, these formulas are used to show that any $p^{th}$ root of unity $ζ$ is not a root of the generic dimension of $M$. To handle the case where $λ$ is not $p$-regular, we employ techniques similar to those used by Drupieski, Nakano and Parshall to show that the module $H^i(λ)$ is not projective over $G_1$ whenever it is nonzero and $λ$ lies outside of the Steinberg block.

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。

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