The concept of light leaving and returning to our universe is not well-defined within our current understanding of physics. In physics, light is considered an electromagnetic wave that travels through space at a constant speed. It does not have a physical presence or consciousness that allows it to leave or reenter the universe.
However, if we speculate on a hypothetical scenario where light could somehow leave our universe and return to it, it would likely have significant consequences and raise profound questions about the fundamental laws of physics. Here are a few speculative possibilities:
Violation of Causality: One of the fundamental principles of physics is causality, which states that an effect must occur after its cause. If light were to leave the universe and return, it would imply a violation of causality because the effect (light returning) would precede its cause (light leaving). This would challenge our understanding of cause and effect and disrupt the logical consistency of our physical laws.
Disruption of Space-Time: Light plays a fundamental role in the structure of space and time according to Einstein's theory of general relativity. If light were to leave and reenter the universe, it could potentially disrupt the fabric of space-time itself. The consequences of such disruptions are difficult to predict, but it could lead to distortions, anomalies, or even the breakdown of our current understanding of space-time.
Energy and Conservation Laws: Light carries energy, and the conservation of energy is a fundamental principle in physics. If light were to leave the universe, it would result in a loss of energy within the system. The return of light would then introduce new energy into the universe. This violation of energy conservation principles would challenge our understanding of the laws of physics.
It's important to emphasize that these speculations are purely hypothetical and are not based on our current scientific understanding. The behavior of light leaving and returning to the universe falls outside the boundaries of our current knowledge and models. Exploring such scenarios would require a significant advancement in our understanding of physics and the nature of the universe.