Coloring linear orders with Rado's partial order
نویسندگان
چکیده
Let 1R be the preorder of embeddability between countable linear orders colored with elements of Rado’s partial order (a standard example of a wqo which is not a bqo). We show that 1R has fairly high complexity with respect to Borel reducibility (e.g. if P is a Borel preorder then P ≤B 1R), although its exact classification remains open.
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عنوان ژورنال:
- Math. Log. Q.
دوره 53 شماره
صفحات -
تاریخ انتشار 2007