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Consistency of max{e, b} < e*

Establish whether it is consistent with ZFC that max{e, b} < e*, where e is the evasion number for ordinary prediction, b is the bounding number, and e* is the evasion number for bounding-prediction.

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Background

The paper introduces variants of the evasion/prediction numbers, including the bounding-prediction versions e* and pr*. The main results separate many such characteristics, but the status of stricter separations involving e* remains unresolved.

The author explicitly points out that, even though models with e < b and b < e are known, the stronger separation max{e, b} < e* is still unknown.

References

In fact, even the consistency of max{e,b} < e* is not known (e* < e* and b < e* are known to be consistent: Brendle [Bre95] proved the consistency of e < b (≤ e*), while he and Shelah [BS_E_and_P_2] proved that of b < e (≤ e*). Also, the latter is obtained as a corollary of Theorem C.).

Cichoń's maximum with evasion number (2401.14600 - Yamazoe, 26 Jan 2024) in Section 6 (Questions)