The concept of an "edge" or "wall" at the edge of the universe is not well-defined in current scientific understanding. The universe, as far as we can observe, appears to be vast and expanding. However, it's important to note that the term "universe" refers to the observable universe, the portion of the cosmos that we can detect and study.
According to the leading cosmological model called the Big Bang theory, the universe originated from a highly dense and hot state around 13.8 billion years ago. Since then, it has been expanding and continues to do so. However, this expansion is not like an explosion that took place at a specific point and propelled matter into preexisting space. Instead, the expansion of the universe means that the distances between galaxies and other cosmic objects are increasing.
Currently, the observable universe is estimated to have a radius of about 46.5 billion light-years due to the expansion of space over time. However, it's important to note that this does not mean the universe is a sphere with a defined "edge" or "wall." Rather, it means that the observable universe has a limited extent based on the age of the universe and the speed of light, which sets the limit of how far we can see.
Beyond the observable universe, there may be regions that we cannot observe due to the finite speed of light and the expansion of space. These regions are often referred to as the unobservable or unknown regions of the universe. Speculating about what lies beyond the observable universe is currently a topic of active scientific research and remains an open question. It's important to approach such ideas with caution, as our knowledge and understanding of the universe are continually evolving based on new observations and discoveries.