The cone of positive-definite quadratic forms is subdivided into aggregates of parallelohedra having certain properties. In E 6, the Σ-subcones are investigated and, in particular, the Σ0-subcone will be described which first occurs in E 6 and which is governed by the group {\cal G}_{E_6^*}. Further the \Sigma_{d+1 \choose 2}\-subcone which is governed by the group {\cal G}_{A_d^*} will be discussed for d = 6.

中文翻译：

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关于 E 6 中的两类特殊平行六面体

正定二次形式的圆锥体被细分为具有某些性质的平行六面体的集合体。在乙 6，研究了 Σ 子锥体，特别是 Σ0-subcone将被描述，它首先出现在乙 6且由群 {\cal G}_{E_6^*} 控制。此外，由群 {\cal G}_{A_d^*} 控制的 \Sigma_{d+1 \choose 2}\-subcone 将被讨论为d= 6。