Physical Realization of Integer Carry Structures via Light‑Intensity Computation

This work presents an optical computing architecture that performs arithmetic operations using light intensity as a continuous physical quantity. By mapping continuous lux values into an 8‑state multi‑valued logic system, the proposed optical CPU physically separates the sum‑mod and carry components of integer addition. A key result is that the carry‑propagation structure—normally an internal and unobservable signal in electronic circuits—emerges as a measurable physical phenomenon: the generation of a carry corresponds to a threshold‑crossing event in light intensity. This provides the first physical observation of the non‑local carry behavior inherent in the digit structure of integers. The architecture implements the Physical layer of the Physical–Logical–Structural Three‑World Model proposed by the authors, establishing a direct connection between integer structure (Structural), multi‑valued logic (Logical), and light‑intensity computation (Physical). In this paper, experimental evaluation is conducted using the minimal 8‑state Optical CPU, demonstrating that integer carry structures can be generated, separated, and observed through light intensity alone. In addition, we present the architecture of a 7‑channel parallel Optical CPU as an extension based on the same physical principles, indicating that the proposed model naturally scales to parallel multi‑valued computation. The experimental results reported here pertain to the minimal configuration; the 7‑channel design is presented as an architectural extension and has not been experimentally evaluated in this work. These findings open a new direction for computation in which integer structure becomes a physically observable and manipulable object.