Carlo Rovelli is an Italian theoretical physicist and writer who has worked in Italy, the United States, France and, since 2020, in Canada. He is also currently a Distinguished Visiting Research Chair at the Perimeter Institute, core member of the Rotman Institute of Philosophy of Western University in Canada, and Fractal Faculty of the Santa Fe Institute in The United States.

Loop quantum gravity (LQG) is a theory of quantum gravity that incorporates matter of the Standard Model into the framework established for the intrinsic quantum gravity case. It is an attempt to develop a quantum theory of gravity based directly on Albert Einstein's geometric formulation rather than the treatment of gravity as a mysterious mechanism (force). As a theory, LQG postulates that the structure of space and time is composed of finite loops woven into an extremely fine fabric or network. These networks of loops are called spin networks. The evolution of a spin network, or spin foam, has a scale on the order of a Planck length, approximately 10−35 meters, and smaller scales are meaningless. Consequently, not just matter, but space itself, prefers an atomic structure.