Could a Grand Unified Theory of Physics Be Impossible?

Katie Robertson has degrees in physics and philosophy. She's now a fellow at the University of Birmingham, where she thinks about how the microscopic laws of physics weave themselves together to form the world we experience from thermodynamics to the arrow of time in black holes. Could a grand unified theory of physics be impossible? To help me tackle this grandest of questions, I've invited a philosopher of physics who spends all her days thinking about this particular question.