On powers of Lindelöf spaces
نویسنده
چکیده
We present a forcing construction of a Hausdorff zero-dimensional Lindelöf space X whose square X is again Lindelöf but its cube X has a closed discrete subspace of size c, hence the Lindelöf degree L(X) = c. In our model the Continuum Hypothesis holds true. After that we give a description of a forcing notion to get a space X such that L(X) = א0 for all positive integers n, but L(X0 ) = c = א2.
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تاریخ انتشار 2010