论文标题
一般基础方案上的弹簧同构
Springer isomorphisms over a general base scheme
论文作者
论文摘要
我们确定了在一般基础方案上还原性群体方案的弹簧同构的存在。为此,我们首先研究了还原群体方案的光纤常规部分的中心化,并且在许多情况下我们建立了它们的平坦度。最后,我们提出了一些论点,以表明我们的结果中的假设基本上是最佳的。我们的结果阐明了施普林格同构的某些方面,即使在一个领域上也是如此,在这种情况下,论点大大简化了。
We establish the existence of Springer isomorphisms for reductive group schemes over general base schemes. For this, we first study centralizers of fiberwise regular sections of reductive group schemes, and we establish their flatness in many cases. At the end, we give several arguments to show that the hypotheses in our results are essentially optimal. Our results clarify some aspects of Springer isomorphisms even over a field, and the arguments simplify considerably in this case.