The complexity of continuous embeddability between dendrites
نویسندگان
چکیده
We show that the quasi-order of continuous embeddability between finitely branching dendrites (a natural class of fairly simple compacta) is Σ1-complete. We also show that embeddability between countable linear orders with infinitely many colors is Σ1-complete.
منابع مشابه
Universality of Embeddability Relations for Coloured Total Orders
Some examples of Σ 1 1-universal preorders are presented, in the form of various relations of embeddability between countable coloured total orders. As an application, strengthening a theorem of [7], the Σ 1 1-universality of continuous embeddability for dendrites whose branch points have order 3 is obtained.
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عنوان ژورنال:
- J. Symb. Log.
دوره 69 شماره
صفحات -
تاریخ انتشار 2004