Abstract
The consistency of a second-order version of Morley’s Theorem on the number of countable models was proved in [EHMT23] with the aid of large cardinals. We here dispense with them.
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Tall, F.D., Zhang, J. The second-order version of Morley’s theorem on the number of countable models does not require large cardinals. Arch. Math. Logic 63, 483–490 (2024). https://doi.org/10.1007/s00153-024-00907-8
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DOI: https://doi.org/10.1007/s00153-024-00907-8
Keywords
- Morley’s theorem
- Countable models
- Cohen forcing
- \(\sigma \)-projective equivalence relations
- Large cardinals
- Generic absoluteness