The Independence of $\delta^1_n$
Leshem, Amir ; Magidor, Menachem
J. Symbolic Logic, Tome 64 (1999) no. 1, p. 350-362 / Harvested from Project Euclid
In this paper we prove the independence of $\delta^1_n$ for n $\geq$ 3. We show that $\delta^1_4$ can be forced to be above any ordinal of L using set forcing. For $\delta^1_3$ we prove that it can be forced, using set forcing, to be above any L cardinal $\kappa$ such that $\kappa$ is $\Pi_1$ definable without parameters in L. We then show that $\delta^1_3$ cannot be forced by a set forcing to be above every cardinal of L. Finally we present a class forcing construction to make $\delta^1_3$ greater than any given L cardinal.
Publié le : 1999-03-14
Classification: 
@article{1183745710,
     author = {Leshem, Amir and Magidor, Menachem},
     title = {The Independence of $\delta^1\_n$},
     journal = {J. Symbolic Logic},
     volume = {64},
     number = {1},
     year = {1999},
     pages = { 350-362},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1183745710}
}
Leshem, Amir; Magidor, Menachem. The Independence of $\delta^1_n$. J. Symbolic Logic, Tome 64 (1999) no. 1, pp.  350-362. http://gdmltest.u-ga.fr/item/1183745710/