I'm reading A Note on a Theorem by Ladner by Balcazar and Diaz, trying to understand the proof of Theorem 2.1. I don't know if it's just old notation, but I'm having quite a bit of trouble.
- In step (a), is $\lambda$ the empty string?
- In step $(c1)$, it lists a sequence as $T(\lambda),T(0),T(0^2),\cdots,T(0^1)$. I don't see an obvious pattern defining this sequence, what is the sequence? And what's the difference between $T(0)$ and $T(0^1)$?
- In step $(c3)$, what does it mean that $T$ will "try to find" a $z$ satisfying those properties? How does it "try" to find it?
- The definition of the transducer $T$ and the language $L_{m+1}$ seems circular. Why do we not run into a chicken and egg conundrum?