Improved Separations between Quantum and Classical Communication Complexity of Total Functions

François Le Gall

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arXiv · 2609.16726

Improved Separations between Quantum and Classical Communication Complexity of Total Functions

François Le Gall

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Abstract

We refine Gavinsky's framework (arXiv:2608.18784) for exponential separations between quantum and randomized communication complexity of total functions and obtain larger separations: polylogarithmic quantum communication versus $\tildeΩ(\sqrt n)$ randomized communication with two quantum messages, and versus $Ω(n^{1-\varepsilon})$ for every fixed $0<\varepsilon<1$ with more quantum messages.

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François Le Gall. 2026-09-15. Improved Separations between Quantum and Classical Communication Complexity of Total Functions. https://arxiv.org/abs/2609.16726

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