I am a theoretical physicist interested in quantum computing, quantum matter, and quantum gravity. My background is in particle physics and quantum field theory (subjects I still love), but in the 1990s I got excited about the possibility of solving otherwise intractable problems by exploiting quantum physics. I have proposed potential applications of quantum computers to quantum simulation and other hard problems, and I have developed methods for protecting quantum systems from decoherence using cleverly designed software and hardware. I am especially intrigued by the ways our deepening understanding of quantum information and quantum computing can be applied to other fundamental issues of physics, such as the classification of topological phases of matter, nonequilibrium quantum dynamics, the quantum properties of black holes, and the quantum structure of spacetime.