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Planting Kurepa trees and killing Jech-Kunen trees in a model by using one inaccessible cardinal

Renling Jin·Saharon Shelah
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Abstract

By an omega_1--tree we mean a tree of power omega_1 and height omega_1. Under CH and 2^{omega_1}> omega_2 we call an omega_1--tree a Jech--Kunen tree if it has kappa many branches for some kappa strictly between omega_1 and 2^{omega_1}. In this paper we prove that, assuming the existence of one inaccessible cardinal, (1) it is consistent with CH plus 2^{omega_1}> omega_2 that there exist Kurepa trees and there are no Jech--Kunen trees, (2) it is consistent with CH plus 2^{omega_1}= omega_4 that only Kurepa trees with omega_3 many branches exist.

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Renling Jin, Saharon Shelah. 1992-11-15. Planting Kurepa trees and killing Jech-Kunen trees in a model by using one inaccessible cardinal. https://arxiv.org/abs/math/9211214

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