A note on Rainwater's Theorem

David Preiss

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arXiv · 2609.36306

A note on Rainwater's Theorem

David Preiss

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Abstract

We extend Rainwater's theorem that, for Baire measures on a compact Hausdorff space,a measure singular with respect to any measure from a $w^*$-compact convex set $M$ of probability measures sits on a Baire set which is $μ$-null for every $μ\in M$. Our main result shows that this statement holds under the weaker assumption of convex analyticity of $M$. In the standard way, this extends the Glicksberg--König--Seever decomposition theorem. We also give conditions for our results to hold for sets of signed measures.

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David Preiss. 2026-09-28. A note on Rainwater's Theorem. https://arxiv.org/abs/2609.36306

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