A MAD Q-set
نویسنده
چکیده
A MAD (maximal almost disjoint) family is an infinite subset A of the infinite subsets of ω = {0, 1, 2, . . .} such that any two elements of A intersect in a finite set and every infinite subset of ω meets some element of A in an infinite set. A Q-set is an uncountable set of reals such that every subset is a relative Gδ set. It is shown that it is relatively consistent with ZFC that there exists a MAD family which is also a Q-set in the topology in inherits a subset of P (ω) = 2.
منابع مشابه
2 4 D ec 2 00 2 A MAD Q - set Arnold
A MAD (maximal almost disjoint) family is an infinite subset A of the infinite subsets of ω = {0, 1, 2, . . . , } such that any two elements of A intersect in a finite set and every infinite subset of ω meets some element of A in an infinite set. A Q-set is an uncountable set of reals such that every subset is a relative Gδ set. It is shown that it is relatively consistent with ZFC that there e...
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تاریخ انتشار 2004