This paper proposes a phenomenological model for the fine-structure constant based on an internal rotational structure combined with relativistic energy considerations. A dimensionless parameter α = rω/c is introduced, and a normalization condition αᵢnt = 1 is assumed for the internal layer, where the rotational velocity reaches the speed of light. Using the relativistic energy–momentum relation and an effective momentum associated with internal rotation, the total energy is expressed as E = mc²√ (1 + α²). By comparing the closed-form expression with its series expansion, a residual term δ = (3/2 − √2) is obtained. It is shown that the square of this residual reproduces the order of magnitude of the fine-structure constant, α ≈ δ² ≈ 1/137, with a deviation of approximately 0. 8%. Furthermore, the structure of the deviation is examined from the viewpoint of hierarchical corrections. An alternating higher-order structure, δ² = α − α³ + α⁵ − α⁷ + ⋯, is discussed as a possible phenomenological representation of internal self-similar structure. The observed discrepancy is shown to be of order α², suggesting that the present model captures the leading-order structure of the fine-structure constant, while higher-order corrections may involve additional hierarchical or geometrical effects not included in the present approximation. This work presents a structural interpretation of the fine-structure constant as an emergent quantity derived from internal rotational dynamics and relativistic corrections.
Hidemi Munakata (Wed,) studied this question.