Work

Impossibility of One-Way One-Round Quantum 4-Coloring via Matrix-Space Stability

Year: 2026
Type: preprint
Abstract: We show that one-way one-round quantum-LOCAL algorithms cannot $4$-color directed cycles with high probability. This is the first lower bound in the high-probability quantum LOCAL setting that goes beyond the non-signaling and bounded-dependence models, exploiting the structure of distributed quantum algorithms. Our proof establishes a bidirectional connection between distributed quantum computing and extremal combinatorics. We obtain our lower bound by proving a Mantel-type stability theorem for weighted matrix spaces.
Language: English
Open Access status: green
OpenAlex ID: W7212048109
Cites: 1
Cited by: 1
Related to: 10