OCW
How did the Milky Way get its shape?
Thirteen billion years ago, the gas and dust particles that eventually became our Milky Way were whizzing around in every direction. Despite the wild motion of its parts, the galaxy as a whole was rotating about an axis. So why did the Milky Way, like most galaxies, become flat, and not spherical li..
TED
How do bulletproof vests work?
By 1975, Richard Davis had been shot at close range 192 times. But not only was he completely healthy, each of those bullets were part of a demonstration to sell his new product: the bulletproof vest. So, how does such a light, flexible piece of clothing stop a bullet? The secret was a synthetic fib..
TED
The secret force for limitless energy? Lasers
In 2022, physicist Tammy Ma and the team at Lawrence Livermore National Laboratory achieved a scientific breakthrough decades in the making: fusion ignition, or the combining of two atoms to generate more energy out of a reaction than was put in — recreating on Earth the same process that powers t..
TED
How does an air conditioner actually work?
Typically, with any piece of technology, you pump one unit of energy in and you get about one out. That’s just the first law of thermodynamics: energy has to be conserved. But there’s a piece of technology called a heat pump, where for every bit of energy you put in, you get three to five times ..
TED
3 mysteries of the universe — and a new force that might explain them
We're still in the dark about what 95 percent of our universe is made of — and the standard model for understanding particle physics has hit a limit. What's the next step forward? Particle physicist Alex Keshavarzi digs into the first results of the Muon g-2 experiment at Fermilab in Chi..
TED
Why can't you put metal in a microwave?
In 1945, engineer Percy Spencer was standing near a RADAR device that produced high-intensity microwaves and noticed that his candy bar had melted. He then exposed popcorn kernels to the magnetron device, and sure enough, they popped. Soon after, the first microwave oven became available, using the ..
TED
