What seasons are and why Earth has them

Stephen Wolfram answers general questions from his viewers about science and technology as part of an unscripted livestream series, also available on YouTube here: https://wolfr.am/youtube-sw-qa

Topics: Three-body problem and computational irreducibility - Climate and radiation on planets with multiple suns - Cherenkov radiation and why it doesn't break relativity Proton decay, particle physics and "how bad would it be?"