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Black Holes essay

DO NOT STEAL. THIS IS MY ESSAY I WROTE FOR 8TH GRADE! It is so bad lmfao. This is from 5 years ago. I just want to archive it

What are black holes according to Stephen Hawking?

When physicist Stephen Hawking wrote his book A Brief History of Time, on many topics on time and the universe, he wrote two whole chapters on black holes. When the book was written, black holes were theoretical. It's only for the first time that a photo was taken in April 2019. This report is going to be based off what Stephen Hawking found out and from the sources he used as well such as Einstein's theory of relativity. Some alternate sources will be used to explain more in a broader and simpler sense of what Hawking said.

Hawking wrote "To understand how a black hole might be formed, we first need an understanding of the life cycle of a star." A star is mostly made up of hydrogen and there is such an immense amount of mass starts to collapse because of the strong gravitational pull. As the atoms build up and start to interact quickly, the gas heats up and the reaction causes the star to shine. Certain stars can eventually form into a white dwarf, a small star with hundreds of tons of mass and can stay this way a very long time. To start off, gravitational pull in a black hole is very strong as shown in the example in the next paragraph. Light cannot escape as it is sucked in and while the star contracts, "the gravitational field at its surface gets stronger and the light cones get bent inward more." The region in which nothing can escape is the black hole.

The entirety of space is three dimensions and in Einstein's theories, the fourth dimension is time. The universe is seen as one sheet or grid. A big object of mass such as a planet falls on the grid and can warp space-time. This means that the gravity is the curvature of the universe. For example, Stephen Hawking was writing (before black holes were 100% proven true), "observations with the Hubble telescope of the galaxy known as M87 reveal that it contains a disk of gas 130 light-years across rotating about a central object two thousand million times the mass of the sun. This can only be a black hole." Hawking was making his point that something with that much mass could only be a black hole because of all the infinite mass surrounding it that gets pulled in forever and this type is categorized as a supermassive black hole.

When black holes were still theoretical, Stephen Hawking made a very interesting point that to detect them, because of the huge gravitational pull and the infinite mass, objects nearby would be affected by this. Any mass of celestial object that comes near the black hole will distort, be sucked in or torn apart. For example, stars' and their, "remains, and gas that is thrown off other stars, will fall toward the black hole." This means that when the stars come too close, the force of the hole will suck it in and could potential release X-rays.

Depending on perspective, an observer would see different things around the hole. If someone was outside a black hole, the gravitation force would be so strong that they would get stretched out like a noodle; this process is called spaghettification. It's not relevant to the collapse except demonstrating the effects of the gravity around the event horizon. The event horizon is the boundary of the blackhole where no light can escape.

Another mathematical physicist, Roger Penrose whom Hawking worked with researched and found out that, "according to general relativity, there must be a singularity of infinite density and space-time curvature within a black hole." In a more simplified idea, this means that a because a black hole has so much mass and can greatly warp spacetime curving it, there has to be a point with infinite mass (the singularity).

Depending on perspective, if an astronaut were to be somewhat close to the black hole, they would see different effects happening. The event horizon is the boundary of black hole and it falls in the way of the light rays. For a simple visual, the event horizon is like the atmosphere on a planet, and the black hole itself is one big black sphere. Hawking describes it as a "one-way membrane." From a view outside the Everything fails to escape from the black hole and it just gets sucked in further and further causing more mass to build up. In my own words, I would say black holes are like an infinite pit where anything can go in and there is enough room and it never comes out but I'm sure someone else has said that.

Hawking wrote a chapter that went more in depth into black holes applying quantum theory into black holes. When applied, it changes the physics and theories of properties of black holes. Because the paper I am writing is talking briefly about black holes, this paper will not mention the quantum theory but summarizing the temperatures, as a black hole loses mass, the temperature increases. It is possible for a black hole to lose mass relating to thermodynamic physics and a type of thermal radiation called Hawking Radiation. In the end, Hawking theorized that when a black hole contracts, it will just "disappear, at least from our region of the universe, taking with it the astronaut and any singularity there might be inside it" and it was an indication of the possibility of removing singularities with the quantum physics applied.

Black holes can be very simple and complex at the same time when it is looked at from different perspectives. They are an interesting topic in the universe and still to this day many questions are lurking around. It is hard to imagine a ball of mass so powerful that it can pull light in that cannot escape. A dense small star evolves into a big ball bigger than the sun and given the scale, that is truly supermassive. Stephen Hawking was a very smart man and probably one of the best of the 20th-21st century. It is probably true that no human will ever get remotely close to a black hole, but even if they did, would they want to go in? I found out so much more than I already knew about black holes especially the more detailed properties. Maybe sometime in the future, I will explore deeper into the topic and go into the physics of black holes and find my own ideas. Hawking did use theories of many other mathematicians and physicists to form his own theories himself. In a parallel universe, perhaps there is an answer to everything and black holes and in our own world, the acquired knowledge of black holes will not be lost in a void of singularity.

Loff, Sarah. "Black Hole Image Makes History; NASA Telescopes Coordinate Observation." NASA. NASA, April 10, 2019. https://www.nasa.gov/mission_pages/chandra/news/black-hole-image-makes-history.

Stephen Hawking, A Brief History of Time, (New York: Random House US, 2018), p. 84

Stephen Hawking, A Brief History of Time, (New York Random House US 2018),p. 88

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 99

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 98

J. Craig Wheeler, Cosmic Catastrophes: Exploding Stars, Black Holes, and mapping the universe, (Cambridge University Press 2007), p. 182

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 90

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 92

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 111

Stephen Hawking, A Brief History of Time, (New York: Random House US 2018), p. 116

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