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arXiv · 2503.11823

Two-particle scattering on general graphs

Luna Lima Keller·Daniel Jost Brod
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Abstract

Quantum walks in general graphs, or more specifically scattering on graphs, encompass enough complexity to perform universal quantum computation. Any given quantum circuit can be broken down into single- and two-qubit gates, which can then be translated into subgraphs -- gadgets -- that implement such unitaries on the logical qubits, simulated by particles traveling along a sparse graph. In this work, we start to develop a full theory of multi-particle scattering on graphs and give initial applications to build multi-particle gadgets with different properties.

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Luna Lima Keller, Daniel Jost Brod. 2025-03-14. Two-particle scattering on general graphs. https://doi.org/10.22331/q-2026-03-23-2038

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