On this episode, we meet with Professor of Physics at UCSD and the Associate Director of CASS, the Center for Astrophysics and Space Sciences, Tom Murphy. Murphy shows us how continued growth and energy use is an impossibility if continued at our current trajectory. How does physics constrain our planetary ambitions? Murphy helps us do the math. To help us align with a post-growth trajectory, Murphy offers suggestions for how humans can begin to treat nature as well as we treat ourselves — and why we must care about the future in order to create a brighter one. About Thomas Murphy Thomas Murphy is a Professor in the Physics Department at UCSD, the Associate Director of CASS, the Center for Astrophysics and Space Sciences, and is the author of Energy and Human Ambitions on a Finite Planet. From 2003–2020, Murphy led the APOLLO project as an ultra-precise test of General Relativity using the technique of lunar laser ranging. Professor Murphy’s interests are transitioning to quantitative assessment of the challenges associated with long-term human success on a finite planet.