How many alien civilizations are out there? | Sara Walker and Lee Cronin and Lex Fridman

Lex Fridman Podcast full episode: https://www.youtube.com/watch?v=SFxIazwNP_0 Please support this podcast by checking out our sponsors: - Uncruise: https://uncruise.com/pages/lex - Linode: https://linode.com/lex to get $100 free credit - ExpressVPN: https://expressvpn.com/lexpod and use code LexPod to get 3 months free - ROKA: https://roka.com/ and use code LEX to get 20% off your first order - Athletic Greens: https://athleticgreens.com/lex and use code LEX to get 1 month of fish oil GUEST BIO: Sara Walker is an astrobiologist and theoretical physicist. Lee Cronin is a chemist. This is a conversation and debate about alien life and alien civilizations. PODCAST INFO: Podcast website: https://lexfridman.com/podcast Apple Podcasts: https://apple.co/2lwqZIr Spotify: https://spoti.fi/2nEwCF8 RSS: https://lexfridman.com/feed/podcast/ Full episodes playlist: https://www.youtube.com/playlist?list=PLrAXtmErZgOdP_8GztsuKi9nrraNbKKp4 Clips playlist: https://www.youtube.com/playlist?list=PLrAXtmErZgOeciFP3CBCIEElOJeitOr41 SOCIAL: - Twitter: https://twitter.com/lexfridman - LinkedIn: https://www.linkedin.com/in/lexfridman - Facebook: https://www.facebook.com/lexfridman - Instagram: https://www.instagram.com/lexfridman - Medium: https://medium.com/@lexfridman - Reddit: https://reddit.com/r/lexfridman - Support on Patreon: https://www.patreon.com/lexfridman