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--- advanced_tools:bianchi_identities [2019/01/16 14:24]
129.13.36.189 [Concrete]
+++ advanced_tools:bianchi_identities [2019/01/16 14:34]
129.13.36.189 [Abstract]
@@ Line 28: / Line 28: @@
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-Bianchi identities express the fact that the boundary of a boundary is always zero. Mathematically this follows by applying Stoke's theorem twice.
+Bianchi identities express the fact that the boundary of a boundary is always zero. Mathematically this follows by applying Stoke's theorem twice. This is discussed explicitly in the book No-Nonsense Electrodynamics by Schwichtenberg
 <tabbox Abstract>
+In general relativity, the Bianchi identity
-<note tip>
+$$ \nabla R = \nabla \nabla \theta =0  $$
-The motto in this section is: //the higher the level of abstraction, the better//.
+roughly says "that the sum over a closed two-dimensional surface of rotations induced by Riemannian curvature is equal to zero." (Source)
-</note>
 <tabbox Why is it interesting?>
 <blockquote>