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Absolute Zero Conquest of Cold

   2007    Technology
This scientific detective tale tells the story of a remarkable group of pioneers who wanted to reach the ultimate extreme: absolute zero, a place so cold that the physical world as we know it doesn't exist, electricity flows without resistance, fluids defy gravity and the speed of light can be reduced to 38 miles per hour. Absolute zero became the Holy Grail of temperature physicists and is considered the gateway to many new technologies, such as nano-construction, neurological networks and quantum computing. The possibilities, it seems, are limitless. The first episode Chronicles the major discoveries leading towards the mastery of cold, beginning with King James I's court magician, Cornelius Drebbel, who managed to air condition the largest interior space in the British Isles in 1620. Other stories will include the first "natural philosopher," Robert Boyle, a founder of the Royal Society in Great Britain; the Grand Duke Ferdinand II de Medici's involvement in the creation of the first thermometer; the establishment of the laws of thermodynamics by three young scientists, Sadi Carnot, James Joule and William Thomson; and Michael Faraday's critical achievement in liquefying several other gases which set the stage for the commercial application of cold to refrigeration and air conditioning.
Series: Absolute Zero

The Hawking Paradox

   2005    Science
Stephen Hawking is the most famous scientist on the planet. But behind the public face lies an argument that has been raging for almost 30 years. Has he been wrong for the last 30 years? Hawking shot to fame in the world of physics when he provided a mathematical proof for the Big Bang theory. This theory showed that the entire universe exploded from a singularity, an infinitely small point with infinite density and infinite gravity. Hawking was able to come to his proof using mathematical techniques that had been developed by Roger Penrose. These techniques were however developed to deal not with the beginning of the Universe but with black holes". Science had long predicted that if a sufficiently large star collapsed at the end of its life, all the matter left in the star would be crushed into an infinitely small point with infinite gravity and infinite density – a singularity. Hawking realised that the Universe was, in effect, a black hole in reverse. Instead of matter being crushed into a singularity, the Universe began when a singularity expanded to form everything we see around us today, from stars to planets to people. Hawking realised that to come to a complete understanding of the Universe he would have to unravel the mysteries of the black hole and its paradoxes

Death Of The Universe

   2008    Science
While scientists have previously theorised about a “Big Crunch” where the universe retracts back to its original size, the discovery of Dark Matter and Dark Energy has placed that hypothesis on the backburner. Some astronomers now believe that if Dark Matter offsets Dark Energy then as the universe slowly expands, stars will gradually fade, running out of fuel and leading to a dark, cold and lifeless universe. Others hypothesise a much more violent end where Dark Energy continues to expand the universe at a greater and greater speed. Stronger than gravity, Dark Energy would pull apart everything down to the fundamental particles – the universe’s very fibres. While the universe’s end may be 50 billion years away, great leaps in science will continue to alter how we believe the universe was formed – and how it will end.

The End of the Universe

   2014    Science
How and when will the Universe end? Gravity and dark matter are poised to annihilate the Universe in a big crunch. Expansion and dark energy may tear it apart. Or, a phase transition could kill us tomorrow in a cosmic death bubble.
Series: How the Universe Works

Numbers as God

   2018    Science
Mathematician Dr Hannah Fry explores the mystery of maths. It underpins so much of our modern world that it's hard to imagine life without its technological advances, but where exactly does maths come from? Is it invented like a language or is it something discovered and part of the fabric of the universe? It's a question that some of the most eminent mathematical minds have been wrestling with. To investigate this question, Hannah goes head first down the fastest zip wire in the world to learn more about Newton's law of gravity, she paraglides to understand where the theory of maths and its practice application collide, and she travels to infinity and beyond to discover that some infinities are bigger than others.
In this episode, Hannah goes back to the time of the ancient Greeks to find out why they were so fascinated by the connection between beautiful music and maths. The patterns our ancestors found in music are all around us, from the way a sunflower stores its seeds to the number of petals in a flower. Even the shapes of some of the smallest structures in nature, such as viruses, seem to follow the rules of maths. All strong evidence for maths being discovered. But there are those who claim maths is all in our heads and something we invented. To find out if this is true, Hannah has her brain scanned. It turns out there is a place in all our brains where we do maths, but that doesn't prove its invented.
Experiments with infants, who have never had a maths lesson in their lives, suggests we all come hardwired to do maths. Far from being a creation of the human mind, this is evidence for maths being something we discover. Then along comes the invention of zero to help make counting more convenient and the creation of imaginary numbers, and the balance is tilted in the direction of maths being something we invented. The question of whether maths is invented or discovered just got a whole lot more difficult to answer
Series: Magic Numbers

Is the Universe a Hologram

   2019    Science    HD
Shocking new evidence has convinced some of the world's greatest physicists that the universe is a hologram. Using cutting-edge technology, they investigate the secrets of black holes and space-time to build the case for this game-changing discovery.
The holographic principle is a supposed property of quantum gravity that states that the description of a volume of space can be thought of as encoded on a lower-dimensional boundary to the region like a gravitational horizon. First proposed by Gerard 't Hooft, it was given a precise string-theory interpretation by Leonard Susskind.
The holographic principle was inspired by black hole thermodynamics, which conjectures that the maximal entropy in any region scales with the radius squared, and not cubed as might be expected. In the case of a black hole, the insight was that the informational content of all the objects that have fallen into the hole might be entirely contained in surface fluctuations of the event horizon.
Series: Space Deepest Secrets