|"Is this all real? Or has this been happening inside my head?"
The subject of this article is a real-life person, group, company, product, or creative work that has been mentioned "in-universe" in a canon source. The Harry Potter Wiki is written from the perspective that all information presented in canon is true (e.g., Hogwarts really exists), and, as such, details contained in this article may differ from real world facts.
The Big Bang is the leading theory among most scientists about how our universe was formed. According to the theory, the universe was once incredibly hot and dense before expanding to the state it is in today.
- Harry Potter and the Prisoner of Azkaban (film) (Mentioned on book cover)