Guram Bezhanishvili , Nick Bezhanishvili , Joel Lucero - Bryan and Jan van Mill S 4 . 3 and hereditarily extremally disconnected spaces
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Research Article Guram Bezhanishvili, Nick Bezhanishvili, Joel Lucero-Bryan and Jan van Mill S4.3 and hereditarily extremally disconnected spaces Abstract: Themodal logic S4.3 de nes the class of hereditarily extremally disconnected spaces (HED-spaces). We construct a countable HED-subspaceX of the Gleason cover of the real closed unit interval [0, 1] such that S4.3 is the logic ofX.
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