In "A Brief History of Time," Stephen Hawking discusses the implications of Einstein's general theory of relativity on the nature of the universe. He emphasizes that this theory suggests that the universe is not infinite and must have a definitive beginning. This aligns with various scientific findings that explore the origin of the cosmos.

Hawking also touches on the possibility of the universe having an end, indicating that the laws of physics could lead to a conclusion of cosmic existence. Through collaboration with Roger Penrose, he highlights the importance of mathematical models in understanding both the beginnings and potential conclusions of the universe's existence.