Fermi's Paradox and the Psychology of Galactic Empires | Matthew O´Dowd | TEDxTUWien
22:52
8 ways the world could suddenly end: Stephen Petranek at TEDxMidwest
17:30
Why We are Alone in the Galaxy | Marc Defant | TEDxUSF
17:42
A Theory You've Never Heard Of | Michael Robinson | TEDxUniversityofHartford
24:02
Is Time Travel, Especially Into the Past Possible? | Matt Szydagis | TEDxSchenectady
10:52
Why I believe in UFOs, and you should too... | Ben Mezrich | TEDxBeaconStreet
10:25
Extraterrestrials - Why They're Almost Certainly Out There... | Chris Crowe | TEDxJohnLyonSchool
16:06
Cosmology and the arrow of time: Sean Carroll at TEDxCaltech
17:58