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0 pointsmrfox3212y ago0 comments

Re [1]: it's fairly concrete to simply say that matrix multiplication can be performed block-wise.

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I don’t disagree; but that is just an example of MM. The gist is not that you can do block multiplication; but that you can define matrices over any non commutative ring, which includes other matrices - ie blocks.

mrfox321OP2y ago

Yeah matrices are more abstract. I guess I am just pointing out that your concrete example of non-commutative rings (matrices of matrices) still needs a proof to demonstrate bijection between 4N x 4N (scalar) and 4 x 4 (N x N(scalar)).

Block MM demonstrates the equivalence.

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PartiallyTyped2y ago

mrfox321OP2y ago

Block MM demonstrates the equivalence.

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