Lee Smolin: Quantum Gravity and Einstein’s Unfinished Revolution

Lex introduces Lee Smolin, a theoretical physicist and co-inventor of loop quantum gravity who contributed to cosmology, quantum field theory, the foundations of quantum mechanics, theoretical biology, and the philosophy of science. Author of The Trouble with Physics and Einstein's Unfinished Revolution, Smolin is an outspoken figure among top theoretical physicists—a world of academics, naked emperors, outcasts, revolutionaries, madmen, and dreamers that Lex finds exciting to explore, recommending past episodes with Susskind, Carroll, Kaku, Tegmark, Weinstein, and Gates.

Lex explains why he talks to physicists despite an AI focus: creating AI requires returning to the fundamental nature of the universe and the human mind, and theoretical physicists venture into dark, psychologically challenging places to force out principles. After the Cash App sponsor read, with a tangent on cryptocurrency and the history of money, he turns to Smolin.

Lex opens with the "easy" question of what is real, and how we distinguish reality from a creation of human perception. Smolin says we don't know—this is science—but he believes there is a world independent of his existence, experience, and knowledge, which he calls the real world. Lex pushes beyond science.

Asked whether everything might be merely a creation of mind, Smolin grants a non-crazy version: our brains actively construct a highly processed experience, not the raw world—yet he still believes a real world lies behind that veil and is curious about it. We are, like our cave ancestors, naturally curious storytellers who must judge fast on incomplete information ("tiger or not?"), so we're often wrong and readily fool ourselves and others.

Asked what it means to be right, Smolin, as a realist, says there's no simple right and wrong but a relative scale: you're more right the closer you come to an exact description of the real world, though we can never know for sure. He denies there is a scientific method, citing Paul Feyerabend, who argued by logic and historical example that any proposed rule of science must sometimes be violated for science to progress.