In "Cycles of Time," Roger Penrose discusses a mathematical approach to understanding the concept of space-time, particularly in relation to the Big Bang. He suggests that it may be possible to think of space-time as having a conformal structure that can be extended slightly before the Big Bang hypersurface. This idea is intriguing, as it challenges the conventional notion that the Big Bang represents the absolute beginning of everything.

Penrose emphasizes that this extension is primarily a mathematical construct, lacking direct physical significance. However, it raises thought-provoking questions about the nature of time and existence itself. The proposition invites contemplation on whether there is any meaningful interpretation of what might precede the Big Bang, even if it is merely a theoretical exercise.