The boundaries between individual universes are theoretical constructs that represent the limits of a specific universe. These boundaries are often referred to as "cosmic horizons" and are defined by the observable universe, which is the portion of the universe that we can see and study.
The boundaries between individual universes are determined by the expansion of the universe and the speed of light. As the universe expands, light from distant objects takes longer to reach us, creating a limit to what we can observe. This limit is known as the cosmic horizon and is considered the boundary of our universe.
Currently, there is no known way to cross the boundaries between individual universes. The laws of physics, as we understand them, prevent us from traveling beyond the cosmic horizon. However, there are theoretical concepts such as wormholes and multiverses that propose ways to breach these boundaries, but they have not been proven.
The boundaries between individual universes challenge our understanding of the universe and its origins. They suggest that there may be multiple universes beyond our own, each with its own set of physical laws and characteristics. This concept opens up new avenues for scientific exploration and raises questions about the nature of reality.
The boundaries between individual universes are constantly evolving as the universe expands. This means that the cosmic horizon, and therefore the boundaries, will continue to move outward as the universe continues to grow. However, it is currently unknown if these boundaries can change in any other way, such as merging with another universe or collapsing in on itself.