Abstract

This note provides a detailed proof of Conner–Gesmundo– Landsberg–Ventura’s result that the border rank of the Kronecker square of the little Coppersmith–Winograd tensor is (q + 2)2 . We also indicate how the same ideas seem to extend to the case of the Kronecker cube, pointing toward the conjectural value (q + 2)m (m ≥ 4), although a full proof is left for future work.