Delve into the intricacies of quantum theory in this 21-minute undergraduate lecture from the University of Oxford's Second Year Quantum Theory course. Explore a formal mathematical statement and proof of Heisenberg's Uncertainty Principle, followed by an in-depth discussion of its physical interpretation. Understand why it's impossible to measure a particle's position and momentum with arbitrary accuracy. Learn about quadratic expressions, position and momentum eigenstates, and gain valuable insights into the mathematical foundations of quantum mechanics. Access additional course materials and related lectures to further enhance your understanding of this fundamental principle in quantum physics.