Fresh subsets of ultrapowers
نویسنده
چکیده
In [8], Shelah and Stanley constructed a κ-Aronszjan tree with an ascent path using κ. We show that κ,2 does not imply the existence of Aronszajn trees with ascent paths. The proof goes through an intermediate combinatorial principle, which we investigate further.
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عنوان ژورنال:
- Arch. Math. Log.
دوره 55 شماره
صفحات -
تاریخ انتشار 2016