The concept of the Big Bang does not involve a specific location in terms of light years where it occurred. The Big Bang is not an explosion that happened at a particular point in space but rather the beginning of the expansion of the universe itself. It is often described as the event from which space, time, and matter originated.
According to the prevailing cosmological model, the universe began as an extremely hot and dense state around 13.7 billion years ago. As the universe expanded, matter and energy spread out, and space itself expanded. It is crucial to understand that the Big Bang did not happen at a specific location within the universe but initiated the expansion of the universe from an incredibly compact state.
The early universe was characterized by a hot, dense, and uniform state, and as it expanded, matter began to clump together due to gravitational attraction. Over time, these clumps of matter evolved into galaxies, galaxy clusters, and other cosmic structures that we observe today.
When scientists talk about the age of the universe or the time since the Big Bang, they refer to the elapsed time since the beginning of the expansion, not the distance from a specific location. The current estimate of 13.7 billion years represents the time that has passed since the universe started expanding from a hot and dense state.
It's worth noting that our understanding of the universe's history and the Big Bang is based on extensive observations, theoretical models, and the interpretation of various cosmic phenomena. However, since we can't observe the universe beyond a certain distance due to the finite speed of light, our knowledge of the earliest moments of the universe is limited.