The discussion centers on the nature of time and space before the Big Bang, with participants questioning whether time and space truly did not exist or if current cosmological models simply cannot describe that period. The Hartle-Hawking no boundary proposal suggests that as one approaches the Big Bang, time and space cease to exist, making the concept of "before" meaningless. There is debate over the terminology of "Big Bang," with some arguing it should refer to the hot, dense state post-inflation rather than an initial singularity. The Borde-Guth-Vilenkin theorem is mentioned, which rules out certain inflationary models extending infinitely into the past, but some argue that alternative models may still exist. Overall, the conversation highlights the complexities and uncertainties in understanding the universe's origins and the limitations of current theoretical frameworks.