We prove the consistency of the failure of the weak diamond Φ λ at strongly inaccessible cardinals. On the other hand, we show that the very weak diamond Ψ λ is equivalent to the statement 2 <λ < 2 λ and hence holds at every strongly inaccessible cardinal.
- Radin forcing
- Very weak diamond
- Weak diamond
All Science Journal Classification (ASJC) codes
- Algebra and Number Theory