Patreon: https://www.patreon.com/seanmcarroll Blog post with audio player, show notes, and transcript: https://www.preposterousuniverse.com/podcast/2021/10/04/167-chiara-marletto-on-constructor-theory-physics-and-possibility/ Traditional physics works within the “Laplacian paradigm”: you give me the state of the universe (or some closed system), some equations of motion, then I use those equations to evolve the system through time. Constructor theory proposes an alternative paradigm: to think of physical systems in terms of counterfactuals — the set of rules governing what can and cannot happen. Originally proposed by David Deutsch, constructor theory has been developed by today’s guest, Chiara Marletto, and others. It might shed new light on quantum gravity and fundamental physics, as well as having applications to higher-level processes of thermodynamics and biology. Chiara Marletto received her DPhil in physics from the University of Oxford. She is currently a research fellow at Wolfson College, University of Oxford. Her new book is The Science of Can and Can’t: A Physicist’s Journey Through the Land of Counterfactuals. Mindscape Podcast playlist: https://www.youtube.com/playlist?list=PLrxfgDEc2NxY_fRExpDXr87tzRbPCaA5x Sean Carroll channel:  https://www.youtube.com/c/seancarroll #podcast #ideas #science #philosophy #culture