On the Jayne-Rogers theorem

Sergey Medvedev

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arXiv · 1706.03624

On the Jayne-Rogers theorem

Sergey Medvedev

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Abstract

In 1982, J.E. Jayne and C.A. Rogers proved that a mapping $f \colon X \rightarrow Y$ of an absolute Souslin-F set X to a metric space Y is $\Delta^0_2$-measurable if and only if it is piecewise continuous. We now give a similar result for a perfectly paracompact first-countable space X and a regular space Y.

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Sergey Medvedev. 2017-06-08. On the Jayne-Rogers theorem. https://arxiv.org/abs/1706.03624

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