TY - JOUR
T1 - On the partially symmetric rank of tensor products of W-states and other symmetric tensors
AU - Ballico, Edoardo
AU - Bernardi, Alessandra
AU - Christandl, Matthias
AU - Gesmundo, Fulvio
PY - 2019
Y1 - 2019
N2 - — Given tensors T and T 0 of order k and k0 respectively, the tensor product T n T 0 is a tensor of order k þ k0. It was recently shown that the tensor rank can be strictly submultiplicative under this operation ([Christandl–Jensen–Zuiddam]). We study this phenomenon for symmetric tensors where additional techniques from algebraic geometry are available. The tensor product of symmetric tensors results in a partially symmetric tensor and our results amount to bounds on the partially symmetric rank. Following motivations from algebraic complexity theory and quantum information theory, we focus on the so-called W-states, namely monomials of the form xd1y, and on products of such. In particular, we prove that the partially symmetric rank of xd11y n n xdk1y is at most 2k1ðd1 þ þ dkÞ.
AB - — Given tensors T and T 0 of order k and k0 respectively, the tensor product T n T 0 is a tensor of order k þ k0. It was recently shown that the tensor rank can be strictly submultiplicative under this operation ([Christandl–Jensen–Zuiddam]). We study this phenomenon for symmetric tensors where additional techniques from algebraic geometry are available. The tensor product of symmetric tensors results in a partially symmetric tensor and our results amount to bounds on the partially symmetric rank. Following motivations from algebraic complexity theory and quantum information theory, we focus on the so-called W-states, namely monomials of the form xd1y, and on products of such. In particular, we prove that the partially symmetric rank of xd11y n n xdk1y is at most 2k1ðd1 þ þ dkÞ.
KW - Partially symmetric rank
KW - cactus rank
KW - tensor rank
KW - W-state
KW - entanglement
U2 - 10.4171/RLM/837
DO - 10.4171/RLM/837
M3 - Journal article
SN - 1120-6330
VL - 30
SP - 93
EP - 124
JO - Atti della Accademia Nazionale dei Lincei, Classe di Scienze Fisiche, Matematiche e Naturali, Rendiconti Lincei Matematica E Applicazioni
JF - Atti della Accademia Nazionale dei Lincei, Classe di Scienze Fisiche, Matematiche e Naturali, Rendiconti Lincei Matematica E Applicazioni
IS - 1
ER -