Imagining a sustainable future - Alex Steffen

View full lesson: http://ed.ted.com/lessons/why-do-some-people-go-bald-sarthak-sinhaUploaded 02-10-14If you are a living, breathing human being, chances are you have felt sad at least a few times in your life. But what exactly is melancholy, and what (if anything) should we do about it? Courtney St…

Dive into the history of the life-saving procedure of blood transfusions and how it has evolved since the 17th century. Uploaded 18-02-20--In 1881, doctor William Halsted rushed to help his sister Minnie, who was hemorrhaging after childbirth. He quickly inserted a needle into his arm, withdrew his…

View full lesson: http://ed.ted.com/lessons/a-trip-through-space-to-calculate-distance-heather-tunnellUploaded 06-09-13Imagine two aliens racing across outer space to their moon. Who can we deem the fastest alien? With DIRT -- or the equation Distance = Rate x Time -- we can calculate their rates, …

What makes crystals grow into their signature shapes? Dig into the atomic patterns and unique properties of crystals.Uploaded 18-06-19--Many crystals have signature shapes— like the cascade of pointed quartz or a pile of galena cubes. Every crystal’s atoms have a defining feature: their organized, …