Matrices as Tensor Network Diagrams
How would one write a cross-product with that?<p>Using two vectors and the epsilon tensor (Levi-Chivita-symbol), I guess?<p><i>Edit:</i> So like this: two circles with one connection each as input, i.e. vectors (a and b), and a tensor with three connections, leaving one, meaning the result will be a vector again.<p><pre><code>  a  o
      \
       o -    (-o c)
      /
  b  o
</code></pre>
Multiplying with another vector c gives the parallelepipedial product (a x b) c, a scalar (also = det(a,b,c)).<p>Cool :)