The splitting number can be smaller than the matrix chaos number
Abstract
Let chi be the minimum cardinal of a subset of 2omega that cannot be made convergent by multiplication with a single Toeplitz matrix. By an application of creature forcing we show that s<chi is consistent. We thus answer a question by Vojtas. We give two kinds of models for the strict inequality. The first is the combination of an aleph2-iteration of some proper forcing with adding aleph1 random reals. The second kind of models is got by adding delta random reals to a model of MA< kappa for some delta in [aleph1,kappa). It was a conjecture of Blass that s=aleph1<chi=kappa holds in such a model. For the analysis of the second model we again use the creature forcing from the first model.
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