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تسجيل مستخدم جديدSchur multipliers of Cartan pairs
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We define the Schur multipliers of a separable von Neumann algebra M with Cartan masa A, generalising the classical Schur multipliers of $B(ell^2)$. We characterise these as the normal A-bimodule maps on M. If M contains a direct summand isomorphic to the hyperfinite II_1 factor, then we show that the Schur multipliers arising from the extended Haagerup tensor product $A otimes_{eh} A$ are strictly contained in the algebra of all Schur multipliers.
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