How To Travel Through.Time • 2009 • episode "S1E6" • Physics of the Impossible

10:29

The equations of physics suggest time should be able to go backwards as well as forwards. Experience suggests, though, that it cannot. Why? And is time travel really possible?

The Economist • 2015 • Physics

5:29

When we look at the sky, we have a flat, two-dimensional view. So how do astronomers figure the distances of stars and galaxies from Earth? Yuan-Sen Ting shows us how trigonometric parallaxes, standard candles and more help us determine the distance of objects several billion light years away from Earth.

TED-Ed • 2014 • Physics

58:15

Award-winning physicist Sean Carroll is known for his keen observations on the relationship between humanity and the laws of nature, and finding where human purpose and meaning fit into a scientific world view.

S1E8 • Curiosity Retreats: 2016 Lectures • 2016 • Physics

11:18

Scientists investigate the way the Sun builds its power -- through fusion -- hoping to find a way to use fusion as a less dangerous and less radioactive waste-producing path to energy than fission. But there are some major difficulties along the way...

2017 • Physics

44:09

The 100 greatest discoveries in Physics!

Physics

57:59

Hannah is going the other way by asking whether everything could, in fact, be smaller. But going smaller turns out not to be much safer... First, we shrink the Earth to half its size - it starts well with lower gravity enabling us to do incredible acrobatics, but things gradually turn nasty as everyone gets altitude sickness - even at sea level. Then we visit Professor Daniel Lathrop's incredible laboratory, where he has built a model Earth that allows us to investigate the other effects of shrinking the planet to half size. The results aren't good - with a weaker magnetic field we would lose our atmosphere and eventually become a barren, lifeless rock like Mars. In our next thought experiment, we shrink people to find out what life is like if you are just 5mm tall. We find out why small creatures have superpowers that seem to defy the laws of physics, meet Jyoti Amge, the world's smallest woman, and with the help of Dr Diana Van Heemst and thousands of baseball players reveal why short people have longer lives. Lastly, the Sun gets as small as a sun can be. We visit the fusion reactor at the Joint European Torus to find out why stars have to be a minimum size or fusion won't happen. And if our Sun were that small? Plants would turn from green to black, and Earth would probably resemble a giant, frozen eyeball. Which all goes to show that size really does matter.

S1E2 • Size Matters with Hannah Fry • 2018 • Physics