A Gdelta ideal of compact sets strictly above the nowhere dense ideal in the Tukey order
نویسندگان
چکیده
We prove that there is a Gδ σ-ideal of compact sets which is strictly above NWD in the Tukey order. Here NWD is the collection of all compact nowhere dense subsets of the Cantor set. This answers a question of Louveau and Veličković asked in [4].
منابع مشابه
A Gδ Ideal of Compact Sets Strictly above the Nowhere Dense Ideal in the Tukey Order
We prove that there is a Gδ σ-ideal of compact sets which is strictly above NWD in the Tukey order. Here NWD is the collection of all compact nowhere dense subsets of the Cantor set. This answers a question of Louveau and Veličković asked in [4].
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عنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 156 شماره
صفحات -
تاریخ انتشار 2008