Quantum Information & Computation
Volume 25, Issue 6
RESEARCH ARTICLE Open access

Random-Projector Quantum Diagnostics of Ramsey Numbers and A Prime-factor Heuristic for R (5, 5) = 45

Fabrizio Tamburini

Author affiliations
  • Fabrizio Tamburini1
  1. Rotonium – Quantum Computing, Le Village by CA, Piazza G. Zanellato, 23, Padova PD, Italy

pp. 739-772 · 10.2478/qic-2025-0039

Abstract

We introduce a statistical framework for estimating Ramsey numbers by embedding two-color Ramsey instances into a ℤ2 × ℤ2 -graded Majorana algebra. This approach replaces brute-force enumeration with two randomized spectral diagnostics applied to operators of a given dimension d associated with Ramsey numbers: a linear projector Plin and an exponential map Pexp (α), suitable for both classical and quantum computation. In the diagonal case, both diagnostics identify R(5, 5) at n = 45. The quantum realizations act on a reduced module and therefore require only five data qubits plus a few ancillas via block-encoding/qubitization for R(5, 5) = 45, in stark contrast to the (n2)≈103\left(\begin{matrix} n \\ 2 \\\end{matrix} \right) \approx {10^3} logical qubits demanded by direct edge encodings. We also provide few-qubit estimates for R(6, 6) and R(7, 7), and propose a simple “prime-sequence” consistency heuristic that connects R(5, 5) = 45 to constrained diagonal growth. Our method echoes Erdős’s probabilistic paradigm, emphasizing randomized arguments rather than explicit colorings, and parallels the classical coin-flip approach to Ramsey bounds. Finally, we discuss potential applications of this framework to machine learning with a limited number of qubits.
Open accessCC BY-NC-ND 4.0

Keywords

  • quantum algorithms
  • ramsey number R(5, 5)
  • random projectors

Suggested citation

Fabrizio Tamburini (2025). Random-Projector Quantum Diagnostics of Ramsey Numbers and A Prime-factor Heuristic for R (5, 5) = 45. Quantum Information & Computation, 25(6), 739-772. https://doi.org/10.2478/qic-2025-0039

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