A space is said to be nearly pseudocompact iff $vX-X$ is dense in $\beta X-X$. In this paper relatively realcompact sets are defined, and it is shown that a space is nearly pseudocompact iff every relatively realcompact open set is relatively compact. Other equivalences of nearly pseudocompactness are obtained and compared to some results of Blair and van Douwen.
@article{118591, author = {John J. Schommer}, title = {Relatively realcompact sets and nearly pseudocompact spaces}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {34}, year = {1993}, pages = {375-382}, zbl = {0781.54019}, mrnumber = {1241747}, language = {en}, url = {http://dml.mathdoc.fr/item/118591} }
Schommer, John J. Relatively realcompact sets and nearly pseudocompact spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 34 (1993) pp. 375-382. http://gdmltest.u-ga.fr/item/118591/
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