§28.1 explicitly allows noncommutative multiplication.
别名:环
按作者与版本查阅
以下按已登记位置排列。出现顺序、原文引用与已登记依赖分别展示;最早位置不代表全书首次定义。
Woit · 2025-10-20
已登记出处中的最早位置:§28.1 · zh-CN。
来源短摘录与定位
§28.1 · zh-CN · machine_draft · machine-draft-not-reviewed
在数学中,“环(ring)”是带加法和乘法的集合,这些运算满足结合律与分配律,但不一定满足交换律;“代数(algebra)”则是同时具有某个标量域上向量空间结构的环。正则对易关系与正则反对易关系分别定义了Weyl代数和Clifford代数。以复数为标量的情形最简单,我们先讨论复数情形,再讨论实数情形。
§28.1 · en · machine_draft · machine-draft-not-reviewed
In mathematics, a “ring” is a set with associative and distributive addition and multiplication laws, not necessarily commutative. An “algebra” is a ring that is also a vector space over a field of scalars. The canonical commutation and anticommutation relations define the Weyl and Clifford algebras, respectively. We begin with complex scalars and then turn to real scalars.