Structural Origin of Quark Masses

This work presents a zero-parameter structural formulation of the quark-mass hierarchy. Using the fixed constants = 136, S = 3124, six quark masses are expressed through a unified structural relation, qmₑ=Kq (3R²S) (8^uqR^{uq+1}S) ⁿ. , the coefficients \ (Kq\) are generated from two structural indices, \d = 2, ᵤ = 2R, correspond to the six quark sectors \ (u, d, c, s, t, b\). The formulation reproduces the observed quark-mass hierarchy across all three generations, including the light-quark scale, the charm and strange masses, the bottom mass, and the top-quark mass scale near \ (173\, GeV\). The result is interpreted conservatively as a structural correspondence between fixed dimensionless ratios and the observed quark-mass spectrum. The top-quark value is not tuned to the latest central value, but is treated as an effective structural mass scale consistent with the known scheme dependence of top-mass determinations. A notable feature of the formulation is the structural asymmetry appearing in the second generation, where the charm and strange sectors follow different correction patterns. This is discussed as a possible transitional layer between the base and higher-order propagation sectors. No free parameters are introduced. No tuning is performed. All quantities arise from the fixed structural relations. A minimal Python implementation is provided for full reproducibility: https: //github. com/yasuotanakaresearch/zero-parameter-structure