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forumfann
Sep5-09, 03:38 AM
Could anyone help me on this question:
Suppose ${e_i}$ is an orthonormal frame, is $\nabla_{e_1}e_j$ is 0 if i is not equal to j?

Any answers or suggestion will be highly appreciated.

HallsofIvy
Sep5-09, 07:09 AM
Could anyone help me on this question:
Suppose ${e_i}$ is an orthonormal frame, is $\nabla_{e_1}e_j$ is 0 if i is not equal to j?

Any answers or suggestion will be highly appreciated.
First, use [ itex ] and [ /itex ] or [ tex ] and [ itex ] (without the spaces) on this forum rather that "$". So your question is
"Suppose \{e_i\} is an orthonormal frame, is \nabla_{e_i}e_j is 0 if i is not equal to j?"

Okay, what does \nabla_{ei}e_j mean?

forumfann
Sep5-09, 10:07 AM
\nabla_{e_{i}}e_{j} is the Levi-Civita connection between e_{i} and e_{j}. Does \nabla_{e_{i}}e_{j} equal 0 if i is not equal to j?

Ben Niehoff
Sep5-09, 02:23 PM
No, not in general, because the frame can rotate.