Five open problems in quantum information

Five selected problems in the theory of quantum information are presented. The first four concern existence of certain objects relevant for quantum information, namely mutually unbiased bases in dimension six, an infinite family of symmetric informationally complete generalized measurements, absolutely maximally entangled states for four subsystems with six levels each and bound entangled states with negative partial transpose. The last problem requires checking whether a certain state of a two-ququart system is 2-copy distillable. Finding a correct answer to any of them will be rewarded by the Golden KCIK Award established by the National Quantum Information Centre (KCIK) in Poland. A detailed description of the problems in question, the motivation to analyze them, as well as the rules for the open competition are provided.

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