Rigidity of decompositions of rank-two matrices into sums of rank-one tensors? – mathoverflow.net

Let $X_1,X_2,X_3,X_4,Y_1,Y_2,Y_3,Y_4 \in \mathbb{C}^n$. Consider rank-one matrices

In the rank-one case, equality of two tensors is completely rigid: if $x_1 ...