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New trace norm inequalities for 2 x 2 blocks of diagonal matrices

Christopher King·Michael Nathanson
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Abstract

Several new trace norm inequalities are established for 2n x 2n block matrices, in the special case where the four n x n blocks are diagonal. Some of the inequalities are non-commutative analogs of Hanner's inequality, others describe the behavior of the trace norm under re-ordering of diagonal entries of the blocks.

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Christopher King, Michael Nathanson. 2003-12-09. New trace norm inequalities for 2 x 2 blocks of diagonal matrices. https://arxiv.org/abs/math/0312194

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