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arXiv · 1606.04496

Effros, Baire, Steinhaus and Non-Separability

A. J. Ostaszewski
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Abstract

We give a short proof of an improved version of the Effros Open Mapping Principle via a shift-compactness theorem (also with a short proof), involving `sequential analysis' rather than separability, deducing it from the Baire property in a general Baire-space setting (rather than under topological completeness). It is applicable to absolutely-analytic normed groups (which include complete metrizable topological groups), and via a Steinhaus-type Sum-set Theorem (also a consequence of the shift-compactness theorem) includes the classical Open Mapping Theorem (separable or otherwise).

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BibTeXRIS

A. J. Ostaszewski. 2016-06-14. Effros, Baire, Steinhaus and Non-Separability. https://doi.org/10.1016/j.topol.2015.09.033

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