Derek Levinson

collaborators

2 papers

math.LO2023

Unreachability of $Γ_{2n + 1, m}$

Derek Levinson

We find bounds for the maximal length of a sequence of distinct $Γ_{2n + 1, m}$ -sets under $A D$ and show there is no sequence of distinct $Γ_{2n + 1}$ -sets of length $\bf{δ^1_…

math.LO2022

Unreachability of Inductive-Like Pointclasses in $L (R)$

Derek Levinson, Itay Neeman, Grigor Sargsyan

Hjorth proved from $Z F + A D + D C$ that there is no sequence of distinct $Σ_{2}^{1}$ sets of length $δ_{2}^{1}$ . Sargsyan extended Hjorth's technique to show there is no sequence of distinc…

Unreachability of Γ2n+1,m​

Unreachability of Inductive-Like Pointclasses in L(R)

Unreachability of $Γ_{2n + 1, m}$

Unreachability of Inductive-Like Pointclasses in $L (R)$