Abstract
We show that the Hrushovski–Fraïssé limit of certain classes of trees lead to strictly superstable theories of various U-ranks. In fact, for each \( \alpha \in \omega +1\backslash \{0\}\) we introduce a strictly superstable theory of U-rank \( \alpha \). Furthermore, we show that these theories are decidable and pseudofinite.
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Acknowledgements
We would like to thank J. Baldwin, C. Laskowski and D. Macpherson for the helpful discussions we had during our stay at the Institute Henri Poincaré (IHP). Hereby, we also would like to thank IHP and CIMPA for supporting our participation in the trimester MOCOVA 2018 held at the IHP. Also, the authors are thankful to the anonymous referee for his useful suggestions and comments.
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Communicated by Hamid Reza Ebrahimi Vishki.
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Valizadeh, A.N., Pourmahdian, M. Strict Superstablity and Decidability of Certain Generic Graphs. Bull. Iran. Math. Soc. 45, 1839–1854 (2019). https://doi.org/10.1007/s41980-019-00234-2
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DOI: https://doi.org/10.1007/s41980-019-00234-2
Keywords
- Hrushovski constructions
- Generic structures
- Strictly superstable
- Lascar rank
- Predimension
- Pseudofinite structures
- Ultraflat graphs