Le degré de Lindelöf est 𝑙-invariant

Bouziad, Ahmed

doi:10.1090/S0002-9939-00-05553-2

Le degré de Lindelöf est $l$-invariant
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Proc. Amer. Math. Soc. 129 (2001), 913-919 Request permission

Abstract:

Two Tychonoff spaces $X$ and $Y$ are said to be $l$-equivalent if $C_{p}(X)$ and $C_{p}(Y)$ are linearly homeomorphic. It is shown that if $X$ and $Y$ are $l$-equivalent, then the Lindelöf numbers of $X$ and $Y$ are the same. The proof given is a strengthening of the one given by N.V. Velichko to show that the Lindelöf property is $l$-invariant.

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