This dataset/paper presents an educational and approximate model of the early universe using a finite universe framework based on Light-Cosmos Theory. It estimates the initial diameter of the universe and the total photon number corresponding to the current cosmic age and the 2. 7 K cosmic microwave background (CMB) temperature. Assuming idealized expansion at the speed of light and ignoring gravity and matter effects, the model shows that the initial universe could have had a diameter of approximately 5. 48 µm and accommodate around 10^89 photons. This work is intended as a conceptual and pedagogical tool for understanding the scale and numerical aspects of cosmic expansion, rather than a precise description of the real universe.
Akihito Sugawara (Sun,) studied this question.