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arXiv · 2502.05733

On definable J-sets

Zhentao Zhang
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Abstract

We study definable J-sets for definable groups and compare them with weakly generic sets. We show that the property that J-sets coincide with weakly generic sets is invariant on enough saturated models, and hence a model-theoretical property. We have positive results for superstable commutative groups and some easy examples in pCF. We also give an example for noncoincidence.

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Zhentao Zhang. 2025-02-09. On definable J-sets. https://arxiv.org/abs/2502.05733

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