Part 2/10:
The Big Bang should not be misunderstood as a mere explosion that occurred in space. Instead, it represents an expansion of space itself. Imagining the event from a perspective existing outside our universe is misleading; in fact, that outside perspective may not even exist. If it did, it would belong to another universe altogether. For those within the universe at the time of the Big Bang, the experience would have been marked by a rapid decline in both temperature and density, heralding the transformation of the cosmos. This monumental event, occurring approximately 13.8 billion years ago, has since given rise to an ever-expanding universe that continues to cool.