Some More Conservation Results on the Baire Category Theorem
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In this paper, we generalize a result of Brown and Simpson [1] to prove that RCA0+Π∞-BCT is conservative over RCA0 with respect to the set of formulae in the form ∃!X φ(X), where φ is arithmetical. We also consider the conservation of Π∞-BCT over Σ1-NIA+∇1-CA. Mathematics Subject Classification: 03F35, 03F60.
[1] Fernando Ferreira,et al. A feasible theory for analysis , 1994, Journal of Symbolic Logic.
[2] Stephen G. Simpson,et al. Subsystems of second order arithmetic , 1999, Perspectives in mathematical logic.
[3] Stephen G. Simpson,et al. The Baire category theorem in weak subsystems of second-order arithmetic , 1993, Journal of Symbolic Logic.