Another proof of Banaschewski's surjection theorem

نویسندگان

  • Ales Pultr Department of Applied Mathematics and ITI, MFF, Charles University, Malostranske nam. 24, 11800 Praha 1, Czech Republic
  • Dharmanand Baboolal School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Durban 4000, South Africa.
  • Jorge Picado Department of Mathematics University of Coimbra PORTUGAL
چکیده مقاله:

We present a new proof of Banaschewski's theorem stating that the completion lift of a uniform surjection is a surjection. The new procedure allows to extend the fact (and, similarly, the related theorem on closed uniform sublocales of complete uniform frames) to quasi-uniformities ("not necessarily symmetric uniformities"). Further, we show how a (regular) Cauchy point on a closed uniform sublocale can be extended to a (regular) Cauchy point on the larger (quasi-)uniform frame.

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عنوان ژورنال

دوره 11  شماره Special Issue Dedicated to Prof. George A. Grätzer

صفحات  113- 130

تاریخ انتشار 2019-07-01

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