The TEDxYouth@IdealeSchool video titled “The Dark Side of the Universe” presented by Rania Chaouech explores the mysterious world of black holes and their role in the cosmos. The video delves into the history of our understanding of space, from the ancient belief that Earth was the center of the universe to the discovery of supermassive black holes at the center of galaxies.
Rania discusses the concept of general relativity and how it shapes our current understanding of gravity and spacetime. She presents a hypothetical scenario of an astronaut being pulled into a black hole, exploring the mind-bending physics behind such an event. The astronaut’s journey into the black hole, experiencing time dilation and spaghettification, highlights the extreme and incomprehensible forces at play in these cosmic phenomena.
The video serves as a fascinating and thought-provoking look at the dark and mysterious side of the universe, leaving viewers with a sense of wonder and curiosity about the secrets that lie beyond our understanding.
Watch the video by TEDxTalks
Author Video Description
What’s a blackhole? Watch Rania’s speech if you want to find out more about our universe a 17 year-old student from Tunisia This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at https://www.ted.com/tedx
[Applause] hello everyone it’s aming to be here tonight okay so um it’s obvious enough I’m going to talk about space um as you might know thousands of years ago philosophers thought that the Earth was the center of the ccle around which uh Sun Moon planets and stars rotate later on they
Discovered that the Earth actually rotated around the Sun and also situated quite far in one of the Milky Ways uh spiral arms named orang arm well the question that actually is unsolved is what actually centers our galaxy well uh in the 1930s an American engineer named Carl jensy discovered a radio signal
Coming from the constellation of Sagittarius towards the center of the Milky Way uh this Galactic signal Source Sagittarius A star was then identified uh in 1974 by astronomers Bruce bik and Robert Brown uh it was during the 1980s that astronomers actually formulated the idea that this Central compact object
Was in fact a black hole of a size until then inimaginable this super massive black hole uh has a mass that is 4 million times uh greater than a our sun makes you feel funy just thinking about it uh now there must be this question that is picking your curiosity or at
Least mine what actually happens if you get sucked into a black hole well uh this question might never be answered because you know everything in space is so far away it would take a Human Being 2 billion kilometers to actually get to Sagittarius A star but uh hypothetically
If we uh ever uh managed to you know with the development of Technology uh physics and science maybe in the future it will be possible to travel far distances in space uh anyway before we jump into any hypothesis you have to know that black holes are one of the
Most mysterious things of our galaxy uh with very very uh a lot of theories revolving around it one of them is the general relativity which is the theory we’re using today to based on an answer uh the general relativity is a theory of space and time this theory was published
By Albert Einstein in 1915 the central idea of uh general relativity is that uh space and time are two aspects of SpaceTime SpaceTime is curved when there is matter energy and momentum resulting in what we perceive as gravity uh now back to the main topic if let’s say hypothetically an astronaut ever
Gets lost in space with a a very very effective heat proof jumpsuit because you know around Sagittarius A Stars a lot of hot gases and stars estimated to be around a billion degrees they would be uh vaporized immediately now this astronaut by lack of luck finds themselves being pulled
Towards the one and only Sagittarius A star now a black hole is is a Sellar object capable of creating a curvature in SpaceTime its gravitational force is so colossal that it deviates light to its gravity Center which gives it that shiny outside look and very very deep Darkness on the
Inside um now this uh astronaut uh would be pulled towards this super massive black hole and and its gravitational force is so massive it would be impossible to turn around and Escape uh in this case uh the a had the luck to fall feet first into the black hole
Otherwise they’d be rotating around it in such an imaginable Force like the moon around Earth just a billion times faster um this astronaut uh sorry uh this as would be observing uh the image of the universe narrowing like they’re getting deep into a black tunnel where they only can observe the light
From where they entered getting smaller and smaller uh now uh they can see from the other side of the light because in some theories you can see uh no because black holes deviates lights obviously and in some theories you can see your reflection before you and next to
You uh the more the astronoid gets dangerously closer the more spectacular phenomena they be observing uh first of all the more they get and closer the more time starts to expand and seconds becomes minutes then hours days years and centuries and the expansion never stops another visual trick is that the
More they’re getting closer the more they’re turning a red tone this is called the Doppler effect if somebody could actually see them they’d see a red flying object going very very very slowly um this astronaut uh would uh be observing um uh no sorry the astronaut uh would be uh observing um
The no with expansion of time the Astron would be observing Stars dying and fusion of galaxies every million years to their eyes would be only a second after some time the ason would have passed a very dangerous pH The Event Horizon this is the border of a black
Hole and the ason is exactly now 13 million kilm away from its gravitational singularity this is the center of a black hole and where all the black hole’s Mass lies well now uh the closest thing to the center in this case his feet are going
To start to expand he would start feel a weird sensation in his legs but to this point there is no visible pain then the asod would feel his whole body starts to expand into a point where even he can’t see it anymore uh he’s experiencing what we call in the general relativity the
Spaghettification this is the last step before the death of any Galactic object and fortunate enough to get sun to to a black hole uh the ass would be so stretched he’d be literally sliced in half and still alive they would continue their spaghettification until they end
Up into a bunch of molecular pieces and finally these pieces would merge with Sagittarius a star’s gravitational singularity and all that is left of our guinea pig is absolute nothingness in the middle of turtle Darkness the end now this is just a hypothesis that obviously has not been proven
Uh this is only based on the general relativity and logically we don’t actually know what happens past the Event Horizon thank you for listening to my speech
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Video “The Dark Side of the Universe | Rania Chaouech | TEDxYouth@IdealeSchool” was uploaded on 02/29/2024 to Youtube Channel TEDx Talks