ON n-TO-ONE CONTINUOUS IMAGES OF βN

نویسندگان

  • ALAN DOW
  • JAN VAN MILL
چکیده

Eric van Douwen [5] produced a maximal crowded extremally disconnected regular space and showed that its Čech–Stone compactification is an at most two-to-one image of βN. We construct for any n = 3 an example of a compact crowded space Xn that is an image of βN under a map all of whose fibers have either size n or n− 1. We also show that under CH this is best possible.

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تاریخ انتشار 2005