A Very Discontinuous Borel Function
Steprans, Juris
J. Symbolic Logic, Tome 58 (1993) no. 1, p. 1268-1283 / Harvested from Project Euclid
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It is shown to be consistent that the reals are covered by $\aleph_1$ meagre sets yet there is a Baire class 1 function which cannot be covered by fewer than $\aleph_2$ continuous functions. A new cardinal invariant is introduced which corresponds to the least number of continuous functions required to cover a given function. This is characterized combinatorially. A forcing notion similar to, but not equivalent to, superperfect forcing is introduced.
Publié le : 1993-12-14
Classification:  
@article{1183744374,
     author = {Steprans, Juris},
     title = {A Very Discontinuous Borel Function},
     journal = {J. Symbolic Logic},
     volume = {58},
     number = {1},
     year = {1993},
     pages = { 1268-1283},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1183744374}
}

Steprans, Juris. A Very Discontinuous Borel Function. J. Symbolic Logic, Tome 58 (1993) no. 1, pp.  1268-1283. http://gdmltest.u-ga.fr/item/1183744374/