论文标题
部分可观测时空混沌系统的无模型预测
On the second cohomology of the norm one group of a p-adic division algebra
论文作者
论文摘要
令$ f $为$ p $ - adic字段,即$ \ mathbb q_p $的有限扩展名。让$ d $是超过$ f $的有限维中心分区代数,让$ sl_1(d)$是$ d $中的norm norm $ 1 $的元素组。 Prasad and Raghunathan proved that $H^2(SL_1(D),\mathbb R/\mathbb Z)$ is a cyclic $p$-group whose order is bounded from below by the number of $p$-power roots of unity in $F$, unless $D$ is a quaternion algebra over $\mathbb Q_2$. In this paper we give an explicit upper bound for the order of $H^2(SL_1(D),\mathbb R/\mathbb Z)$ for $p\geq 5$ and determine $H^2(SL_1(D),\mathbb R/\mathbb Z)$ precisely when $F$ is cyclotomic, $p\geq 19$ and the degree of $D$ is not a power of $p$.
Let $F$ be a $p$-adic field, that is, a finite extension of $\mathbb Q_p$. Let $D$ be a finite-dimensional central division algebra over $F$ and let $SL_1(D)$ be the group of elements of reduced norm $1$ in $D$. Prasad and Raghunathan proved that $H^2(SL_1(D),\mathbb R/\mathbb Z)$ is a cyclic $p$-group whose order is bounded from below by the number of $p$-power roots of unity in $F$, unless $D$ is a quaternion algebra over $\mathbb Q_2$. In this paper we give an explicit upper bound for the order of $H^2(SL_1(D),\mathbb R/\mathbb Z)$ for $p\geq 5$ and determine $H^2(SL_1(D),\mathbb R/\mathbb Z)$ precisely when $F$ is cyclotomic, $p\geq 19$ and the degree of $D$ is not a power of $p$.