Two models that show the interpolation theorem fails in all L1(Qα) and L1,1 (Qα) α= 0,1,2,…
Bulletin of the London Mathematical Society
The logics L1(Q), L1,1(Q) and L2(Q) are formed by adding quantifiers Q, Q1,1 and Q2 respectively to the first-order logic. In this paper, for each ordinal α (including α = 0), we construct two Qa models to prove that the Interpolation Theorem fails in L(Q) and L1,1(Q). © 1992, Oxford University Press. All rights reserved.
Talebi, Norollah, "Two models that show the interpolation theorem fails in all L1(Qα) and L1,1 (Qα) α= 0,1,2,…" (1992). Articles & Book Chapters. 448.