Open Access
2007 Bounds on Weak Scattering
Gerald E. Sacks
Notre Dame J. Formal Logic 48(1): 5-31 (2007). DOI: 10.1305/ndjfl/1172787542
Abstract

The notion of a weakly scattered theory T is defined. T need not be scattered. For each $\cal A$ a model of T, let sr($\cal A$) be the Scott rank of $\cal A$. Assume sr($\cal A$) ≤ ω\sp A \sb 1 for all $\cal A$ a model of T. Let σ\sp T \sb 2 be the least Σ₂ admissible ordinal relative to T. If T admits effective k-splitting as defined in this paper, then $∃θ < σ\sp T \sb 2 such that sr($\cal A$) < θ for all $\cal A$ a model of T.

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Copyright © 2007 University of Notre Dame
Gerald E. Sacks "Bounds on Weak Scattering," Notre Dame Journal of Formal Logic 48(1), 5-31, (2007). https://doi.org/10.1305/ndjfl/1172787542
Published: 2007
Vol.48 • No. 1 • 2007
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