HQET and Fermilab Method for Heavy-Quark Mass Extraction in Lattice QCD — E8 Intelligence Research

FINDING: HQET provides a systematic expansion in inverse heavy-quark mass (1/m_Q) for lattice QCD mass extraction, with the Fermilab method combining nonrelativistic heavy quarks and staggered light quarks to determine heavy-quark masses via one-loop lattice perturbation theory. | MATH: HQET Lagrangian: L = h̄_v (iv·D) h_v + (1/2m_Q) h̄_v (iD_⊥)^2 h_v + (c_F g_s/4m_Q) h̄_v σμν Gμν h_v + O(1/m_Q^2); mass relation: m_B = m_b + Λ̄ - (λ_1 + 3λ_2)/(2m_b) + ...; Fermilab method: m_Q = (m_H - m_light) + δm_pert (one-loop lattice PT); staggered quark action: χ(x) → (-1)x_1+...+x_4 χ(x) for spin-doubling removal. | CONNECTION: The 1/m_Q expansion mirrors the ratio structure of the golden ratio family — the leading term (iv·D) is the "1" (dominant), the kinetic term scales as 1/m_Q, and the spin term as 1/m_Q with coefficient c_F. The staggered phase factor (-1)Σx_μ is a Z_2 × Z_2 × Z_2 × Z_2 symmetry — a hypercubic lattice structure (the 4D analogue of Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com