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I have the expression $$nn\cdot A $$

Where $n$ is a vector, $A$ is a matrix, and $\cdot$ is the dot product. This apparently evaluates to a matrix, but that makes no sense, as dot products only apply to vectors right?

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up vote 1 down vote accepted

You may want to give more context, but things like this occasionally come up in physics. For instance $$r\cdot\sigma=x\sigma_x+y\sigma_y+z\sigma_z,$$ where $\sigma_i$ are Pauli matrices. The result of this is a sum of three matrices which is again a matrix.

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