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IEEE Transactions on Information Theory

Classical Capacity of Classical-Quantum Arbitrarily Varying Channels

Rudolf Ahlswede, Vladimir M. Blinovsky

Published Jan 23, 2007• 47 citations
Publisher

Abstract

We prove that the average error classical capacity C(W) of a classicalquantum arbitrarily varying channel (cq-AVC) W equals 0 or else the random code capacity C (Ahlswede's dichotomy). We also establish a necessary and sufficient condition for C(W)>0
DOI
10.1109/tit.2006.889004

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We derive a regularized formula for the common randomness assisted entanglement transmission capacity of finite arbitrarily varying quantum channels (AVQC's). For finite AVQC's with positive capacity for classical message transmission we show, by derandomization through classical forward communication, that the random capacity for entanglement transmission equals the deterministic capacity for entanglement transmission. This is a quantum version of the famous Ahlswede dichotomy. In the infinite case, we derive a similar result for certain classes of AVQC's. At last, we give two possible definitions of symmetrizability of an AVQC.