Existential Physics: A Scientist's Guide to Life's Biggest Questions

Sabine Hossenfelder examines the intersection of theoretical physics and philosophy, distinguishing between established scientific facts and what she calls "ascientific" speculation. She addresses fundamental questions regarding the nature of time, the existence of free will, and the possibility of a multiverse. By applying the laws of thermodynamics and quantum mechanics, she explains why the past still exists and why the concept of a "now" is scientifically subjective. The text breaks down specific frameworks like reductionism and determinism to show how mathematical models limit or support certain metaphysical beliefs about the beginning of the universe and the persistence of information.

Readers interested in the boundaries of human knowledge will find a clear distinction between empirical evidence and mathematical guesswork. This book serves those who want to understand how general relativity and particle physics impact personal identity and consciousness without the inclusion of spiritual pseudoscience. The reader gains a realistic perspective on what science can actually prove about reality, leaving behind popular myths for a more disciplined understanding of how the cosmos functions. They finish the book knowing which big questions are solvable through evidence and which remain matters of faith.