The cup subalgebra of a II_1 factor given by a subfactor planar algebra   is maximal amenable
  To every subfactor planar algebra was associated a II_1 factor with a canonical abelian subalgebra generated by the cup tangle. Using Popa's approximative orthogonality property, we show that this cup subalgebra is maximal amenable. 
Arnaud Brothier
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