Can’t Quantum Gravity Theories All Get Along? An Interview with Karen Crowther [Video]

When physicists get stuck, call in the philosophers.

The nice thing about philosophers of physics is that they have no dog in the fight among string theory, loop quantum gravity, and other competing approaches to a fundamental theory of nature. They can stand back and offer some third-party perspective. One who specializes in this is Karen Crowther, a postdoc in the University of Geneva philosophy department. She analyzes the assumptions, stated and unstated, that proponents of different theories make and in fact finds they’re not as far apart in their thinking as oft claimed.

In this interview, which I filmed in June 2017 at a conference on quantum gravity organized by Christian Wüthrich at Geneva and Nick Huggett at the University of Illinois in Chicago, she discusses three such assumptions: UV completeness (full unification occurs only on the most minute scales), correspondence (new theories reproduce not only the results of existing theories, but also their mathematical structure), and analogy (reasoning that applies to hot coals and crystals carries over to more exotic systems).

In her conference talk, now available on YouTube, you can also watch her dissect other words that physicists toss around, such as “fundamental” and “emergence.”