A New w-Stable Plane

Gianluca Paolini


We use a variation on Mason’s α-function as a pre-dimension function to construct a not one-based ω–stable plane P (i.e. a simple rank 3 matroid) which does not admit an algebraic representation (in the sense of matroid theory) over any field. Furthermore, we characterize forking in Th(P), we prove that algebraic closure and intrinsic closure coincide in Th(P), and we show that Th(P) fails weak elimination of imaginaries, and has Morley rank ω.

AMS Subject Classification: 03C45, 05B35

Słowa kluczowe: Hrushovski constructions, matroids, w-stable structures

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