A noncommutative extended de Finetti theorem |
| |
Authors: | Claus Kö stler |
| |
Affiliation: | University of Illinois at Urbana-Champaign, Department of Mathematics, Altgeld Hall, 1409 West Green Street, Urbana, 61801, USA |
| |
Abstract: | The extended de Finetti theorem characterizes exchangeable infinite sequences of random variables as conditionally i.i.d. and shows that the apparently weaker distributional symmetry of spreadability is equivalent to exchangeability. Our main result is a noncommutative version of this theorem.In contrast to the classical result of Ryll-Nardzewski, exchangeability turns out to be stronger than spreadability for infinite sequences of noncommutative random variables. Out of our investigations emerges noncommutative conditional independence in terms of a von Neumann algebraic structure closely related to Popa's notion of commuting squares and Kümmerer's generalized Bernoulli shifts. Our main result is applicable to classical probability, quantum probability, in particular free probability, braid group representations and Jones subfactors. |
| |
Keywords: | Noncommutative de Finetti theorem Distributional symmetries Exchangeability Spreadability Noncommutative conditional independence Mean ergodic theorem Noncommutative Kolmogorov zero-one law Noncommutative Bernoulli shifts |
本文献已被 ScienceDirect 等数据库收录! |
|