TY - JOUR
T1 - Multilinear transference of Fourier and Schur multipliers acting on non-commutative Lp-spaces
AU - Caspers, Martijn
AU - Krishnaswamy-Usha, Amudhan
AU - Vos, Gerrit
PY - 2022
Y1 - 2022
N2 - Let G be a locally compact unimodular group, and let φ be some function of n variables on G. To such a φ, one can associate a multilinear Fourier multiplier, which acts on some n-fold product of the noncommutative L
p-spaces of the group von Neumann algebra. One may also define an associated Schur multiplier, which acts on an n-fold product of Schatten classes S
p(L
2(G). We generalize well-known transference results from the linear case to the multilinear case. In particular, we show that the so-called multiplicatively bounded (p1,....,pn)-norm"of a multilinear Schur multiplier is bounded above by the corresponding multiplicatively bounded norm of the Fourier multiplier, with equality whenever the group is amenable. Furthermore, we prove that the bilinear Hilbert transform is not bounded as a vector-valued map L
p1(R,S
p1) × L
p2 (R,S
p2), → L
1(R,S
1), whenever p1 and p2 are such that {equation presented}. A similar result holds for certain Calderón-Zygmund-type operators. This is in contrast to the nonvector-valued Euclidean case.
AB - Let G be a locally compact unimodular group, and let φ be some function of n variables on G. To such a φ, one can associate a multilinear Fourier multiplier, which acts on some n-fold product of the noncommutative L
p-spaces of the group von Neumann algebra. One may also define an associated Schur multiplier, which acts on an n-fold product of Schatten classes S
p(L
2(G). We generalize well-known transference results from the linear case to the multilinear case. In particular, we show that the so-called multiplicatively bounded (p1,....,pn)-norm"of a multilinear Schur multiplier is bounded above by the corresponding multiplicatively bounded norm of the Fourier multiplier, with equality whenever the group is amenable. Furthermore, we prove that the bilinear Hilbert transform is not bounded as a vector-valued map L
p1(R,S
p1) × L
p2 (R,S
p2), → L
1(R,S
1), whenever p1 and p2 are such that {equation presented}. A similar result holds for certain Calderón-Zygmund-type operators. This is in contrast to the nonvector-valued Euclidean case.
KW - Fourier multipliers
KW - multilinear maps
KW - non-commutative Lspaces
KW - Schur multipliers
UR - http://www.scopus.com/inward/record.url?scp=85141495944&partnerID=8YFLogxK
U2 - 10.4153/S0008414X2200058X
DO - 10.4153/S0008414X2200058X
M3 - Article
AN - SCOPUS:85141495944
SN - 0008-414X
VL - 75
SP - 1986
EP - 2006
JO - Canadian Journal of Mathematics
JF - Canadian Journal of Mathematics
IS - 6
ER -