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Absolute extensors in extension theory

Alex Karasev·Vesko Valov
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Abstract

Let L be a countable and locally finite CW complex. Suppose that the class of all metrizable compacta of extension dimension not greater than L contains a universal element which is an absolute extensor in dimension L. Our main result shows that L is quasi-finite.

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Alex Karasev, Vesko Valov. 2004-05-12. Absolute extensors in extension theory. https://arxiv.org/abs/math/0405212

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