2 papers
math.OA2024
A post-group theoretic perspective on the operator-valued S-transform in free probability
Kurusch Ebrahimi-Fard, Timothé Ringeard
We investigate the algebraic structure underlying Voiculescu's S-transform in the setting of operator-valued free probability. We show that its twisted factorisation property gives…
math.CO2024
Planar binary trees, noncrossing partitions and the operator-valued S-transform
Kurusch Ebrahimi-Fard, Timothe Ringeard
We revisit the twisted multiplicativity property of Voiculescu's S-transform in the operator-valued setting, using a specific bijection between planar binary trees and noncrossing…