A Hypothetical Model of the Universe Based on Cosmic Microwave Background Radiation and the Observable Universe

The standard cosmological model holds that the Cosmic Microwave Background (CMB) is a one-time "afterglow" of the Big Bang. However, this paper points out that radiation produced by a one-time explosion must decay to an unobservable level on a timescale of 13.8 billion years, which contradicts the observational fact that the CMB still exists stably and uniformly. Based on this contradiction, this paper proposes a hypothetical cosmic structure model with a central point and an energy gradient. The core assumption of the model: The singularity of the Big Bang did not disappear, but evolved into a continuously existing white hole structure, as the unique source of matter and energy in the universe, which has been continuously outputting outward since its birth. This output drives the universe to present a radial energy gradient distribution — the temperature is higher near the center and lower near the edge. The observable universe where humanity is located happens to be in the gentle zone of the gradient, so the observed CMB appears uniform. The model further infers that the universe has a real physical boundary composed of early ejected hydrogen, making the universe a closed system at the material level. Based on this, the model gives two clear predictions that can be falsified by future observations: If the universe moves toward heat death, the CMB will first dim and cool from the edge direction; If the universe moves toward collapse, the CMB will first brighten and heat up from the central direction. This model does not require the introduction of dark matter and dark energy, and provides a unified explanation for the long-term existence of the CMB, cosmic expansion, the irreversibility of time, and the structure of the cosmic boundary, offering a brand-new theoretical framework for human understanding of the universe. Keywords: cosmic microwave background, cosmic central point, white hole, energy gradient, heat death, cosmic boundary