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A Sky Full of Ghosts

   2014    Science
Tyson begins the episode by explaining the nature of the speed of light and how much of what is seen of the observable universe is from light emanated from billions of years in the past. Tyson further explains how modern astronomy has used such analyzes via deep time to identify the Big Bang event and the age of the universe. Tyson proceeds to describe how the work of Isaac Newton, William Herschel, and James Clerk Maxwell contributed to understanding the nature of electromagnetic waves and gravitational force, and how this work led towards Albert Einstein's Theory of Relativity, that the speed of light is a fundamental constant of the universe and gravity can be seen as distortion of the fabric of space-time. Tyson describes the concept of dark stars as postulated by John Michell which are not visible but detectable by tracking other stars trapped within their gravity wells, an idea Herschel used to discover binary stars. Tyson then describes the nature of black holes, their enormous gravitational forces that can even capture light, and their discovery via X-ray sources such as Cygnus X-1. Tyson uses the Ship of Imagination to provide a postulate of the warping of spacetime and time dilation as one enters the event horizon of the black hole, and the possibility that these may lead to other points within our universe or others, or even time travel. Tyson ends on noting that Herschel's son, John would be inspired by his father to continue to document the known stars as well as contributions towards photography that play on the same nature of deep time used by astronomers.
Series: Cosmos: A Spacetime Odyssey

Weirder and Weirder

   2018    Science
Dr Hannah Fry explores a paradox at the heart of modern maths, discovered by Bertrand Russell, which undermines the very foundations of logic that all of maths is built on. These flaws suggest that maths isn't a true part of the universe but might just be a human language - fallible and imprecise. However, Hannah argues that Einstein's theoretical equations, such as E=mc2 and his theory of general relativity, are so good at predicting the universe that they must be reflecting some basic structure in it. This idea is supported by Kurt Godel, who proved that there are parts of maths that we have to take on faith.
Hannah then explores what maths can reveal about the fundamental building blocks of the universe - the subatomic, quantum world. The maths tells us that particles can exist in two states at once, and yet quantum physics is at the core of photosynthesis and therefore fundamental to most of life on earth - more evidence of discovering mathematical rules in nature. But if we accept that maths is part of the structure of the universe, there are two main problems: firstly, the two main theories that predict and describe the universe - quantum physics and general relativity - are actually incompatible; and secondly, most of the maths behind them suggests the likelihood of something even stranger - multiple universes.
We may just have to accept that the world really is weirder than we thought, and Hannah concludes that while we have invented the language of maths, the structure behind it all is something we discover. And beyond that, it is the debate about the origins of maths that has had the most profound consequences: it has truly transformed the human experience, giving us powerful new number systems and an understanding that now underpins the modern world.
Series: Magic Numbers

Secrets of Time Travel

   2019    Science
Could time travel ever be science fact? Time itself may be something you can bend and stretch. Trying to understand if time travel can be possible teach us a lot about the universe. It forces us to take on some of the toughest unanswered questions in all of physics and will ultimately probably lead to deeper understanding of the very nature of the cosmos.
Series: How the Universe Works Series 8

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

Gravity and Me The Force that Shapes our Lives

   2017    Science
Professor Jim Al-Khalili investigates the amazing science of gravity. A fundamental force of nature, gravity shapes our entire universe. It sculpts galaxies and warps space and time. But gravity’s strange powers also affect our daily lives in the most unexpected ways. This is a story with surprises in store for Jim himself. In telling the story of gravity, his own understanding of the nature of reality comes to be challenged. Finally, Jim discovers that, despite incredible progress, gravity still has many secrets to unveil.

How Time and Consciousness Arise

   2024    Science    HD
The documentary, an own production, immerses the viewer in a journey that blends science and philosophy, questioning the nature of time and unveiling a 4-dimensional universe, where space and time are integrated. We are invited to consider a universe in which past, present, and future coexist, suggesting that our linear perception of time might be more of a mental construction than a physical reality. The narrative progresses by exploring how quantum particles exist in states of probability until they are observed, at which point they acquire defined properties. Then, the provocative hypothesis is presented that observation also fixes the temporal dimension of the particles.
The sensation of the flow of time and the distinction between past, present, and future are introduced as mental constructions, arising from the human brain's limited capacity to process the complexity of reality. It is then proposed that the mind, by observing itself, fixes itself in the temporal dimension, thus creating the illusion of the present. Finally, the impact of these theories on free will is discussed.
This documentary challenges viewers to look beyond their everyday perceptions and consider the possibility that reality is much more complex and fascinating than our immediate experiences suggest. It is an invitation to explore the limits of science, philosophy, and the mind itself in search of answers to some of the deepest questions of existence.
More information on https://www.javier-serrano.blog/Ciencia/representacion_tridimensional_del_universo.php