Interview, Fireside Chat
Adam Frank: Alien Civilizations and the Search for Extraterrestrial Life | Lex Fridman Podcast #455
- Data regarding the prevalence of alien civilizations is expected within the next 10 to 30 years, with predictions that planets are ubiquitous and habitable worlds likely exist around each star.
- Current research utilizing a giant laser at the University of Rochester aims to simulate conditions at super-Earth centers involving pressures millions of times Earth's surface pressure to understand planetary formation.
- Planetary evolution and life are linked to geological turmoil; plate tectonics may have ramped up a billion years ago, increasing net primary productivity by nearly a thousandfold, while biological evolution may require giant catastrophes.
- The introduction of oxygen photosynthesis 2.5 billion years ago created new evolutionary possibilities, and a common impact 65 million years later cleared the path for human rise from small mammals.
- If humanity survives climate change and other threats, the long-term goal is expanding to the entire solar system, with millions to billions of people potentially living in space habitats within a few hundred years.
- A self-sufficient Mars base is estimated to remain unachievable for at least two to three centuries, meaning it is not currently a viable backup plan, though some bacterial survival is deemed possible if introduced.
- While civilizations may be common, they likely constitute a "graveyard" in the galaxy due to short lifespans, with steady states only reached if a civilization survives 10,000 to 100,000 years, leaving regions empty for millions of years.
- Detecting a technological civilization within 10 light-years would be a historic discovery triggering a multi-generational probe project, with potential signatures including propulsion plumes, asteroid-chewing dust, or gamma-ray sprays from warp drive.
- The James Webb Space Telescope is predicted to be critical for characterizing exoplanet atmospheres at the edge of direct imaging capabilities, while artifacts on the Moon from 500 million years ago could remain visible due to slow micro-meteorite gardening.
- Risks include the possibility of human conflict within the solar system, the potential for technology to flatten out rather than advance indefinitely, and the uncertainty of whether intelligent life can easily survive off its home planet.
- The technosphere must mature to last tens of thousands to millions of years, as humans are not currently autopoietic, and the fate of Earth is inextricably combined with the fate of life.
- If the probability of a technological civilization forming is above $10^{-22}$, such civilizations are predicted to have occurred in history, though a fossil record of ancient civilizations hundreds of millions of years ago would be impossible to detect.