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Aug 22, 2017 at 16:06 history edited Qmechanic
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Apr 30, 2017 at 17:52 vote accept Mikkel Rev
Apr 30, 2017 at 9:51 history edited Qmechanic CC BY-SA 3.0
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Apr 30, 2017 at 9:50 answer added Qmechanic timeline score: 12
Apr 29, 2017 at 23:21 comment added Mikkel Rev @knzhou By your first comment, I believe you confirm that you're puzzled too, correct? Flipping the indecies is exactly what I propose, but that's what the lecture notes do not.
Apr 29, 2017 at 23:09 comment added knzhou The upstairs/downstairs index placement is a red herring that can only add confusion; it's not a 'real' index because $\Lambda$ is not a tensor.
Apr 29, 2017 at 23:08 comment added knzhou I think you're put an extra flip in there somewhere. Just think about it like matrices: $ABC = D$ means $A_{ij} B_{jk} C_{k\ell} = D_{i\ell}$. Therefore $A^T BC = D$ means $B_{jk} A_{ji} C_{k\ell} = D_{i\ell}$ where I used the commutativity of multiplication, and replaced $A_{ij}$ with $A_{ji}$. This is exactly the same as equation (1).
Apr 29, 2017 at 22:31 history edited Qmechanic CC BY-SA 3.0
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Apr 29, 2017 at 22:18 history asked Mikkel Rev CC BY-SA 3.0