The isomorphism problem for ω-automatic trees
نویسندگان
چکیده
منابع مشابه
The isomorphism problem for ω-automatic trees
The main result of this paper is that the isomorphism for ω-automatic trees of finite height is at least has hard as second-order arithmetic and therefore not analytical. This strengthens a recent result by Hjorth, Khoussainov, Montalbán, and Nies [9] showing that the isomorphism problem for ω-automatic structures is not Σ 2 . Moreover, assuming the continuum hypothesis CH, we can show that the...
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The main result of this paper states that the isomorphism for ω-automatic trees of finite height is at least has hard as second-order arithmetic and therefore not analytical. This strengthens a recent result by Hjorth, Khoussainov, Montalbán, and Nies [HKMN08] showing that the isomorphism problem for ωautomatic structures is not in Σ 2 . Moreover, assuming the continuum hypothesis CH, we can sh...
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15 صفحه اولThe Isomorphism Problem for k-Trees Is Complete for Logspace
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 2013
ISSN: 0168-0072
DOI: 10.1016/j.apal.2012.09.001