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An engineering explainer on why Tesla abandoned the induction motor for the Model 3 and used an IPM-SynRM design. It covers the reluctance torque and permanent magnet principles behind the choice.

Kurzgesagt explores the idea that life might have arisen shortly after the Big Bang, when the whole universe was warm enough to be habitable. It discusses what that would mean for the origin and spread of life.

A ten-minute explainer from Hypermind on the wisdom of crowds, covering Galton's discovery and the diversity theorem. It argues that collective intelligence comes from diversity, independence and aggregation.

Vsauce explores math through card tricks and big numbers, including an animation of how enormous 52 factorial, the number of deck orderings, really is.

A two-minute explanation of what a rocket mass heater is, starting from how a conventional wood stove works and why creosote and chimney fires occur. It shows how burning hot and storing the heat in thermal mass makes for an efficient heater.

A video explaining why Japanese cities look the way they do, through Japan's national tiered zoning system that permits mixed use and flexible development. It compares this approach with more restrictive zoning elsewhere.

Kurzgesagt explains black hole stars, a hypothesized kind of giant star with a black hole at its core that could be a route to early supermassive black holes.

Kurzgesagt explains why, even with science-fiction technology, most of the universe is permanently out of reach because of cosmic expansion and finite resources.

Tom Scott explains how decades of deep coal mining sank parts of Germany's Ruhr Valley and changed its drainage. Pumps run by Emschergenossenschaft must now work permanently to keep towns and cities from flooding.

PBS Space Time explains how general relativity permits warp drive in principle and covers recent theoretical advances toward solving the negative energy problem.