# A direct product theorem for one-way quantum communication

@article{Jain2020ADP, title={A direct product theorem for one-way quantum communication}, author={Rahul Jain and Srijita Kundu}, journal={Proceedings of the 36th Computational Complexity Conference}, year={2020} }

We prove a direct product theorem for the one-way entanglement-assisted quantum communication complexity of a general relation f⊆X×Y×Z. For any 0 < ε < δ < 1/2 and any k ≥ 1, we show that [EQUATION] where Q1ε(f) represents the one-way entanglement-assisted quantum communication complexity of f with worst-case error ε and fk denotes k parallel instances of f. As far as we are aware, this is the first direct product theorem for the quantum communication complexity of a general relation - direct…

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