evidence: A video shared on social media purportedly shows SpaceX CEO Elon Musk claiming belief in the flat earth theory. [...] The Twitter post claims Musk recently appeared on Joe Rogan’s podcast and stated his belief in the flat Earth theory. The Twitter post allegedly shows a conversation between podcaster Joe Rogan and Musk. "Elon Musk trying to break the firmament," text over the video reads. "Elon is a Flat Earther." [...] There have been other claims of Musk promoting the flat earth theory. One Twitter user claimed Musk tweeted out the theory, but no such tweet could be found.