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+1 vote

We came across it in the Fierz Transformation tutorial. But did not understand the purpose of free and fixed indices.

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1 Answer

+1 vote

Read the chapter on indices in the reference manual,

https://cadabra.science/notebooks/ref_indices.html

Hope that helps; if it doesn't, reply to this and I'll make another attempt.

answered by (45.3k points)
Curved and Flat Indices
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