Groups in supersimple and pseudofinite theories

نویسندگان

  • Richard Elwes
  • Eric Jaligot
  • Dugald Macpherson
  • Mark Ryten
چکیده

We consider groups G interpretable in a supersimple finite rank theory T such that T eq eliminates ∃∞. It is shown that G has a definable soluble radical. If G has rank 2, then if G is pseudofinite it is soluble-by-finite, and partial results are obtained under weaker hypotheses, such as unimodularity of the theory. A classification is obtained when T is pseudofinite and G has a definable and definably primitive action on a rank 1 set.

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تاریخ انتشار 2010