The concept of "before" the Big Bang is a subject of ongoing scientific and philosophical debate, and our understanding of it is limited. The prevailing scientific theory suggests that the universe as we know it originated from a singularity—an infinitely dense and hot point—approximately 13.8 billion years ago in an event commonly referred to as the Big Bang. However, what might have existed before this event is still not fully understood.
The nature of time itself is intricately tied to the fabric of the universe, and our understanding of time breaks down at the moment of the Big Bang singularity. According to our current understanding, the concept of "before" the Big Bang may not have any meaningful significance, as time as we perceive it may have come into existence along with the universe.
Various cosmological models, such as the cyclic or multiverse theories, propose alternative explanations for what may have preceded or potentially coexisted with our universe. These theories suggest the existence of other universes or cycles of expansion and contraction, but they remain speculative and are still areas of active research and exploration.
It's important to acknowledge that our knowledge and understanding of the origins of the universe are continually evolving, and scientists are working to gather more evidence and refine our theories. However, the question of what existed "before nothing" or how the universe came into existence ultimately remains a subject of ongoing investigation and theoretical exploration.