We give an explicit description of the category of central extensions of a group scheme by a sheaf of Abelian groups. Based on this, we describe a framework for computing with central extensions of finite locally free commutative group schemes, torsors under such group schemes and groups of isomorphism classes of these objects.

中文翻译：

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有限群方案的扩展和扭转

我们通过一组阿贝尔群给出了群方案的中心扩展范畴的明确描述。在此基础上，我们描述了一个计算框架，该框架具有有限局部自由交换群方案、此类群方案下的tors以及这些对象的同构类群的中心扩展。