Universal absolute extensors in extension theory

Karasev, Alex; Valov, Vesko

doi:10.1090/S0002-9939-06-08304-3

Universal absolute extensors in extension theory
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Proc. Amer. Math. Soc. 134 (2006), 2473-2478 Request permission

Abstract:

Let $L$ be a countable and locally finite CW complex. Suppose that the class of all metrizable compacta of extension dimension $\le [L]$ 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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