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Ilijas Farah - $\textrm{Exp}(N^\ast)$ need not be an $N^\ast$-image

ILIJAS FARAH, York University, Toronto, Ontario  M3J 1P3, Canada
$\textrm{Exp}(N^\ast)$ need not be an $N^\ast$-image

We prove, using an idea due to M. Bell, that the Cech-Stone remarinder of the integers does not map onto its exponential space. This result uses the Open Coloring Axiom, OCA, and it is another instance of the effect of OCA to structures closely related to real numbers which is opposite to the effect of Continuum Hypothesis (see [1]). References

1.  I. Farah, Completely additive liftings. Bull. Symb. Logic 4(1998), 37-54.