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15Comparison of the deformation behaviour of commercially pure titanium and Ti–5Al–2.5Sn at 296 and 728 KPhilosophical Magazine 93 (21): 2875-2895. 2013.
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507Does the solar system compute the laws of motion?Synthese 198 (4): 3203-3220. 2019.The counterfactual account of physical computation is simple and, for the most part, very attractive. However, it is usually thought to trivialize the notion of physical computation insofar as it implies ‘limited pancomputationalism’, this being the doctrine that every deterministic physical system computes some function. Should we bite the bullet and accept limited pancomputationalism, or reject the counterfactual account as untenable? Jack Copeland would have us do neither of the above. He att…Read more
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25A nonlow2 R. E. Degree with the Extension of Embeddings Properties of a low2 DegreeMathematical Logic Quarterly 48 (1): 131-146. 2002.We construct a nonlow2 r.e. degree d such that every positive extension of embeddings property that holds below every low2 degree holds below d. Indeed, we can also guarantee the converse so that there is a low r.e. degree c such that that the extension of embeddings properties true below c are exactly the ones true belowd.Moreover, we can also guarantee that no b ≤ d is the base of a nonsplitting pair
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12Ct ChongIn Edward R. Griffor (ed.), Handbook of computability theory, Elsevier. pp. 140--298. 1999.
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46The minimal e-degree problem in fragments of Peano arithmeticAnnals of Pure and Applied Logic 131 (1-3): 159-175. 2005.We study the minimal enumeration degree problem in models of fragments of Peano arithmetic () and prove the following results: in any model M of Σ2 induction, there is a minimal enumeration degree if and only if M is a nonstandard model. Furthermore, any cut in such a model has minimal e-degree. By contrast, this phenomenon fails in the absence of Σ2 induction. In fact, whether every Σ2 cut has minimal e-degree is independent of the Σ2 bounding principle
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