An introduction to generalized descriptive set theory, part 3

יום ב', 07/01/2019 - 13:00
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Abstract: 
After introducing the notions of $\kappa$-Borel class, $\kappa$-$\Delta_1^1$ class, $\kappa$-Borel^* class we saw some subset relations between them in the previous talk ( http://u.math.biu.ac.il/~morenom3/GDST-2018.pdf ). We finished the previous talk with a sketch of the proof of:
if  V=L, then $\kappa$-Borel* class is equal to the $\Sigma1^ 1(\kappa)$ class.
We will see this proof in complete detail, starting from the key lemma, Lemma 1.13 on the notes.