Abstract
We introduce the notion of filtration between topologies and study its stabilization properties. Descriptive set theoretic complexity plays a role in this study. Filtrations lead to natural transfinite sequences approximating a given equivalence relation. We investigate those.
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Acknowledgments
I thank Assaf Shani for pointing out paper [4] to me. I also thank the referee for a careful reading of the paper and for pointing out a gap, which has been repaired, in one of the arguments in an earlier version of it.
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Research supported by NSF grant DMS-1800680.
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Solecki, S. Transfinite sequences of topologies, descriptive complexity, and approximating equivalence relations. Isr. J. Math. 242, 933–953 (2021). https://doi.org/10.1007/s11856-021-2153-x
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DOI: https://doi.org/10.1007/s11856-021-2153-x