• Gladaed@feddit.org
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        6 days ago

        A*B is not B*A in every calculus. Imagine what if the entries where matrices themselves.

        Let me show you in 2 D instead of 5:

        (a,b)^T*(a,b) = {(a * a, b * a),(ab, bb)}

        Where () are row vectors, power of T is transposition and {()} is a matrix.

        • Gobbel2000@programming.dev
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          6 days ago

          It’s not that I’m expecting Chinese to be commutative, but the original image makes it look as such, with the upper and lower triangles of the matrix having the same symbols. In your 2D example this would be like having ab on the top right as well (I would give an example of the characters, but I cannot write Chinese).

      • jdr@lemmy.ml
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        6 days ago

        Context? Torsion? Shitty OCR?

        I think Imperial Chinese Geometry considers it one of the great open questions.