Monads of infinite points and finite product spaces
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- by Frank Wattenberg PDF
- Trans. Amer. Math. Soc. 176 (1973), 351-368 Request permission
Abstract:
The notion of “monad” is generalized to infinite (i.e. non-near-standard) points in arbitrary nonstandard models of completely regular topological spaces. The behaviour of several such monad systems in finite product spaces is investigated and we prove that for paracompact spaces X such that $X \times X$ is normal, the covering monad $\mu$ satisfies $\mu (x,y) = \mu (x) \times \mu (y)$ whenever x and y have the same “order of magnitude.” Finally, monad systems, in particular non-standard models of the real line, R, are studied and we show that in a minimal nonstandard model of R exactly one monad system exists and, in fact, $\mu (x) = \{ x\}$ if x is infinite.References
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Additional Information
- © Copyright 1973 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 176 (1973), 351-368
- MSC: Primary 54D15; Secondary 02H25
- DOI: https://doi.org/10.1090/S0002-9947-1973-0312463-9
- MathSciNet review: 0312463