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。
Szekeres · source-snapshot-bc3404156f6e
已登记出处中的最早位置:§18.4 · zh-CN。
来源短摘录与定位
§18.4 · zh-CN · translation · unreviewed
这个联络称为由度量张量所定义的黎曼联络(Riemannian connection)。一个不施加条件 (i) 的物理理论的有趣例子是爱因斯坦–嘉当理论,其中挠率表示自旋 [9]。条件 (ii) 具有以下推论。设是一条具有切向量的曲线,并设和是沿平行移动的向量场,从而。由式 (18.18) 可知,它们的内积沿该曲线为常数:
§18.4 · en · original_transcription · unreviewed
This connection is called the Riemannian connection defined by the metric tensor . An interesting example of a physical theory that does not impose condition (i) is the Einstein– Cartan theory where torsion represents spin [9]. Condition (ii) has the following consequence. Let be a curve with tangent vector , and let and be vector fields parallel transported along , so that . By Eq. (18.18) it follows that their inner product is constant along the curve: