A matrix-discrepancy argument proves tight one-way quantum lower bounds for collision finding (Ω(N^{1/4})) and for streaming triangle finding (Ω(√Δ_V)) where Boolean-Hidden-Matching reductions fail.
Communication Complexity of Collision
1 Pith paper cite this work. Polarity classification is still indexing.
abstract
The Collision problem is to decide whether a given list of numbers $(x_1,\ldots,x_n)\in[n]^n$ is $1$-to-$1$ or $2$-to-$1$ when promised one of them is the case. We show an $n^{\Omega(1)}$ randomised communication lower bound for the natural two-party version of Collision where Alice holds the first half of the bits of each $x_i$ and Bob holds the second half. As an application, we also show a similar lower bound for a weak bit-pigeonhole search problem, which answers a question of Itsykson and Riazanov (CCC 2021).
fields
quant-ph 1years
2026 1verdicts
ACCEPT 1representative citing papers
citing papers explorer
-
Quantum Communication Lower Bounds for Search Problems via Matrix Discrepancy
A matrix-discrepancy argument proves tight one-way quantum lower bounds for collision finding (Ω(N^{1/4})) and for streaming triangle finding (Ω(√Δ_V)) where Boolean-Hidden-Matching reductions fail.