Hechler’s theorem for the null ideal
@article{Burke2004HechlersTF, title={Hechler’s theorem for the null ideal}, author={Maxim R. Burke and Masaru Kada}, journal={Archive for Mathematical Logic}, year={2004}, volume={43}, pages={703-722} }
Abstract.We prove the following theorem: For a partially ordered set Q such that every countable subset of Q has a strict upper bound, there is a forcing notion satisfying the countable chain condition such that, in the forcing extension, there is a basis of the null ideal of the real line which is order-isomorphic to Q with respect to set-inclusion. This is a variation of Hechler’s classical result in the theory of forcing. The corresponding theorem for the meager ideal was established by…
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