Construction under Martin's axiom of a Boolean algebra with the Grothendieck property but without the Nikodym property
Abstract
Improving a result of M. Talagrand, under the assumption of a weak form of Martin's axiom, we construct a totally disconnected compact Hausdorff space K such that the Banach space C(K) of continuous real-valued functions on K is a Grothendieck space but there exists a sequence (μn) of Radon measures on K such that μn(A)0 for every clopen set A⊂eq K and ∫Kfdμn0 for some f∈ C(K). Consequently, we get that Martin's axiom implies the existence of a Boolean algebra with the Grothendieck property but without the Nikodym property.
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