Abstract
Let \({\cal P}_w\) denote the set of weak degrees of nonempty \(\Pi^0_1\) classes in the Cantor space 2ω. We show that \({\cal P}_w\) is not a Heyting algebra. This is a solution to a question presented by Simpson [3].
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Higuchi, K. (2010). \({\cal P}_w\) Is Not a Heyting Algebra. In: Ferreira, F., Löwe, B., Mayordomo, E., Mendes Gomes, L. (eds) Programs, Proofs, Processes. CiE 2010. Lecture Notes in Computer Science, vol 6158. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-13962-8_21
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DOI: https://doi.org/10.1007/978-3-642-13962-8_21
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-13961-1
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