Quantum gravity refers to a set of theories, including string theory, that seeks to unify the macroscopic world of gravity, governed by general relativity, with the microscopic world of quantum physics. At the core of the mystery is the question of whether gravity and the spacetime it inhabits can be “quantized,” or broken down into individual components (hypothetically a graviton), a hallmark of the quantum world. Cracking the problem of quantum gravity would be one of the greatest achievements