The concept of an "infinitely old" universe raises philosophical and conceptual questions about time and the nature of existence itself. It's important to note that our current scientific understanding of the universe suggests that it had a beginning, commonly referred to as the Big Bang, around 13.8 billion years ago. However, discussing the implications of an infinitely old universe can still be an interesting exercise.
If we imagine an infinitely old universe, the notion of "before" and "after" becomes challenging to define. The concept of time as we understand it relies on a linear progression from past to present to future. In the case of an infinitely old universe, there wouldn't be a specific starting point or an endpoint. Time would extend indefinitely into the past.
When contemplating what might exist "before" an infinitely old universe, we enter a realm beyond our current understanding. Some theories propose the existence of a cyclical universe, where one universe gives rise to another in an eternal cycle. However, these are speculative ideas that are still subject to scientific investigation and debate.
It's worth noting that our current understanding of the universe is primarily based on observational evidence and theoretical models that are consistent with the Big Bang theory. Exploring the nature of existence beyond the Big Bang and the implications of an infinitely old universe requires further scientific advancements and a deeper understanding of the fundamental laws of physics.