Could a “demon” break one of the most fundamental laws of physics? Maxwell’s demon has puzzled physicists for more than 150 years. What began as a thought experiment about heat and entropy is now part of our understanding of information, computation and the laws of thermodynamics. Physicist John Goold explains the paradox and what the demon reveals about the relationship between entropy, measurement and the quantum world.

Quantum physicist Vlatko Vedral proposes a radical new vision of reality, one in which observers don’t exist, there are no particles and there is no space or time. Instead, for Vedral, quantum numbers, also known as Q numbers, are the true essence of reality, and it’s a much more beautiful and useful way to understand the world.