For this question, please refer to Chapter 33 page 638, Set Theory Millennium Edition, by Thomas Jech.
The proof of analytic games $G_A$ is converted into an open game $G^ast$ on some suitable space. In the game $G^ast$, Player I plays $a_0$, then Player II plays a pair $(b_0, h_0)$, then I plays $a_1$, followed by II playing $(b_1, h_1)$, and so on. Each $h_i$ is an order preserving function from $K_i$ into $kappa$ (refer to the text for the definition of $K_i$). If Player II is able to construct the $h$'s such that $h_{i+1}$ extends $h_i$ for each $iinomega$, then Player II wins. This game $G^ast$, as mentioned, is an open game.
I would like to know specifically what the payoff set is and what the space is (including the topology).
I came up with the following:
The space is $kappa^K$, where $K=bigcup_{ssubseteq x}K_s$, $x=langle a_0, b_0, ldotsrangle$ formed at the end of the run, and the topology is just like that of the Baire space. The payoff set in $G^ast$ is $A^ast={finkappa^K:f;text{is not order preserving}}$. This set is closed by showing that the complement is open (easy). Hence, the game $G^ast$ is an open/closed game.
The above seem plausible, but the issue I have with the set I came up with is
it doesn't look like a set that include a "pair" as in $(b_0, h_0)$, for instance, does not appear anywhere, and
the set $K$ is particular to the $x=langle a_0, b_0, ldotsrangle$ produced.
I would appreciate if you could let me know if the above is right and provide me a hint as to how to relate to the related notion of a homogeneous tree thereafter. If the above doesn't makes sense, please let me know where it went wrong and a hint as to how to get the right open set in what topological space would be nice.
Thanks!
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