Daytime • 2006 • episode "S1E1" • BBC: Time

4:49

Light always travels at a speed of 299,792,458 meters per second. But if you're in motion too, you're going to perceive it as traveling even faster -- which isn't possible! In this second installment of a three-part series on space-time, CERN scientists Andrew Pontzen and Tom Whyntie use a space-time diagram to analyze the sometimes confounding motion of light.

TED-Ed • Physics

44:09

The 100 greatest discoveries in Physics!

Physics

87:15

Extra dimensions of space — the idea that we are immersed in hyperspace — may be key to explaining the fundamental nature of the universe. Relativity introduced time as the fourth dimension, and Einstein’s subsequent work envisioned more dimensions still — but ultimately hit a dead end. Modern research has advanced the subject in ways he couldn’t have imagined. John Hockenberry joins Brian Greene, Lawrence Krauss, and other leading thinkers on a visual tour through wondrous spatial realms that may lie beyond the ones we experience.

World Science Festival • 2015 • Physics

48:53

We hold a unique knowledge of time, realising that it stretches deep into the past, and will continue into the future. How does this affect our sense of who we are?

S1E3 • BBC: Time • 2006 • 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

5:22

How do we know what matter is made of? The quest for the atom has been a long one, beginning 2,400 years ago with the work of a Greek philosopher and later continued by a Quaker and a few Nobel Prize-winning scientists. Theresa Doud details the history of atomic theory.?

TED-Ed • Physics