English

A compact topology for $\sigma$-algebra convergence

Probability 2021-05-20 v3 Functional Analysis

Abstract

We propose a sequential topology on the space of sub-σ\sigma-algebras of a separable probability space (Ω,F,P)(\Omega,\mathcal{F},\mathbb{P}) by linking conditional expectations on L2L^{2} along sequences of sub-σ\sigma-algebras. The varying index of measurability is captured by a bundle space construction. As a consequence, we establish the compactness of the space of sub-σ\sigma-algebras. The proposed topology preserves independence and is compatible with join and meet operations.

Keywords

Cite

@article{arxiv.1802.05920,
  title  = {A compact topology for $\sigma$-algebra convergence},
  author = {Patrick Beissner and Jonas M. Tölle},
  journal= {arXiv preprint arXiv:1802.05920},
  year   = {2021}
}

Comments

There is a gap in the proof of Theorem 2.6 on page 12, Proof of Claim 3: the tower-type property cannot be applied in the asserted generality

R2 v1 2026-06-23T00:24:30.197Z