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Converse separation: generically c.e. but not coarsely c.e. at level Σα+2

Determine whether there exists a countable linear ordering L and a computable ordinal α such that L is Σα+2-generically computably enumerable (c.e.) but not Σα+2-coarsely c.e.

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Background

The paper proves that for every computable ordinal α, there are linear orderings that are Σα+2-coarsely c.e. but not Σα+2-generically c.e. (Proposition 4.2), establishing a one-directional separation between generic and coarse computability at arbitrarily high levels.

The authors explicitly leave open the converse direction: whether there exist linear orderings that are Σα+2-generically c.e. yet fail to be Σα+2-coarsely c.e., which would demonstrate a strict non-coincidence of these notions at the same level from the opposite direction.

References

Note that we leave the converse construction open. Question 4.3. Is there a linear ordering that is Σα+2-generically c.e. but not Σα+2-coarsely c.e.?

Generically Computable Linear Orderings (2401.14598 - Calvert et al., 26 Jan 2024) in Question 4.3, Section 4.1