The Biggest Ideas in the Universe is a series of videos where I talk informally about some of the fundamental concepts that help us understand our natural world. Exceedingly casual, not overly polished, and meant for absolutely everybody.
This is the Q&A video for Idea #6, "Spacetime." I try to explain what is meant by "photons do not experience time," and why the speed of light has the value it does.
My web page: http://www.preposterousuniverse.com/
My YouTube channel: https://www.youtube.com/c/seancarroll
Mindscape podcast: http://www.preposterousuniverse.com/podcast
The Biggest Ideas playlist: https://www.youtube.com/watch?v=HI09kat_GeI&list=PLrxfgDEc2NxZJcWcrxH3jyjUUrJlnoyzX&ab_channel=SeanCarroll
Blog posts for the series: http://www.preposterousuniverse.com/blog/category/biggest-ideas-in-the-universe/
Background image: https://www.amazon.com/Spacetime-Geometry-Introduction-General-Relativity-ebook/dp/B07T9MCTWF/
#science #physics #ideas #universe #learning #cosmology #philosophy #math #spacetime #relativity