tree property;
successors of singulars;
forcing;
SUCCESSORS;
D O I:
10.1017/jsl.2019.4
中图分类号:
O1 [数学];
学科分类号:
0701 ;
070101 ;
摘要:
We construct a model in which the tree property holds in. aleph(omega+1) and it is destructible under Col(omega, omega(1)). On the other hand we discuss some cases in which the tree property is indestructible under small or closed forcings.