Condensed matter theory and the end of quantum, temperature, and gravity

One of the central themes of condensed matter physics is the emergence of entirely new laws of physics upon combining many interacting parts into one coherent whole. A single atom, for example, has no notion of 'rigidity' or 'speed of sound', but a collection of many atoms in a solid piece of material does have these properties. The lesson of condensed matter that 'more' can be inherently 'different,' applies more broadly. In this inaugural lecture, I will discuss how emergence can help us understand some of the most fundamental problems in modern theoretical physics: the quantumclassical crossover, the meaning of temperature in quantum systems, and the connection between gravity and quantum physics.