Monthly Archives: May 2025

EP 297 Sara Walker on the Physics of Life’s Emergence



Jim talks with Sara Walker about the ideas in her new book Life as No One Knows It: The Physics of Life’s Emergence. They discuss Sara’s path from theoretical physics to astrobiology, the biggest scientific questions, philosophy of science & theory development, historical approaches to origin of life research, Schrödinger’s negative entropy concept, Prigogine’s dissipative systems, information as a causal force at life’s origin, emergence as a scientific concept, constructor theory of information, Assembly Theory as a framework for detecting life, assembly index & copy number as measurable properties, complexity vs randomness, the physical nature of time in complex systems, how Assembly Theory redefines life beyond Earth-centric definitions, planetary-scale perspectives on life’s origins, measurements of exoplanet atmospheres, addressing the error catastrophe problem, Sara’s collaboration with Lee Cronin, the application of Assembly Theory to minerals & planetary atmospheres, the Fermi Paradox & observational horizons, constraints on Drake equation parameters, and much more.

Sara Walker is a theoretical physicist interested in the origins of life and discovering alien life on other worlds. She is Deputy Director of the Beyond Center for Fundamental Concepts in Science, a Professor in the School of Earth and Space Exploration at Arizona State University and an External Faculty at the Santa Fe Institute. Her recognition as a leading scientist includes a Stanley Miller Early Career award, and a Schmidt Sciences Polymath award. Her research team at ASU is internationally regarded for their work at the forefront of building fundamental, and testable theory for understanding what life is. She is also widely regarded for her public intellectual work advancing our understanding of life, which includes her popular science book Life as No One Knows It: The Physics of Life’s Emergence and appearances on podcasts such as Star Talk with Neil de Grasse Tyson, the Joe Rogan Experience, and the Lex Fridman podcast.