You've felt cold before. Sometimes it's cold outside. But what if I told you that "cold" isn't real? There's no substance or quantity called "cold" in science. We can't measure the amount of "cold" in something. Instead it's about what's NOT there.
Ever wonder how the heart symbol came to stand for the actual heart? And why do we speak of the heart as the seat of love, when love really happens in our brains? Is it true that animals only get a billion heartbeats? This week, we give you enough cool cardiac science to make your heart skip a beat.
Why do we sleep? We spend a third of our lives in slumber, but science has yet to determine exactly why we have do it. Here’s a look at how sleep works, why we’re not getting enough sleep, what happens if you DON’T sleep, and an idea about where sleep came from in the first place.
2015 • Health
Richard Feynman was one of the most brilliant theoretical physicists and original thinkers of the 20th century. He rebuilt the theory of quantum electrodynamics, and it was for this work that he won the Nobel Prize in 1965. In 1981, he gave Horizon a candid interview, talking about many things close to his heart.
Zach charts a journey to determine whether time travel is possible. He meets a man who claims to have traveled back in time due to a secret government program and a group of people living in Liverpool known as “time slippers.” Zach then makes an visit to the CERN headquarters in Geneva, where he attempts to understand the origins of the universe and the dimension of time. Equipped with this new knowledge, Zach tests his own perception of time with an elaborate skydiving experiment to see if he can slow down time itself.
2018 • Physics
In the summer of 1939 Albert Einstein was on holiday in a small resort town on the tip of Long Island. His peaceful summer, however, was about to be shattered by a visit from an old friend and colleague from his years in Berlin. The visitor was the physicist Leo Szilard. He had come to tell Einstein that he feared the Nazis could soon be in possession of a terrible new weapon and that something had to be done.
Physicist Jim Al-Khalili routinely deals with the strangest subject in all of science - quantum physics, the astonishing and perplexing theory of sub-atomic particles. But now he's turning his attention to the world of nature. Can quantum mechanics explain the greatest mysteries in biology?