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EDITORIAL/국제 :: Worldpost

In Memory of A Fallen Star


In Memory of A Fallen Star | English Columnist Michelle Lee


Born in Oxford, England, Dr. Stephen Hawking was known for his groundbreaking research in theoretical physics, quantum mechanics, cosmology. When attending the University of Oxford, he pursued interests such as thermodynamics, relativity and quantum mechanics. At the age of 21 as he arrived in University of Cambridge, he was diagnosed with a Motor Neuron Disease called ALS, also known as Lou Gehrig’s Disease. It is a disease in which the motor neurons in your brain and spinal cord slowly die. Patients experience gradual deterioration of muscle movement, and have difficulty swallowing, eating, breathing and speaking and often have a life expectancy of five years. However, Dr. Hawking exceeded the doctors’ predictions and lived on for years until his death at the age of 76 on March 14th, 2018 whilst continuing his search to prove the mysteries of our cosmos. In memory of his loss and as a true admirer of his work, I’ve decided to share some of his greatest contributions to the science community. Although I doubt anyone could possibly understand the mechanics of his thoughts, here’s a shot.

 

1)    When and How did our universe begin?


Hawking worked on the basic laws that govern the universe with his former professor and colleague, Roger Penrose. Using Albert Einstein’s General Theory of Relativity* Hawking and Penrose showed that Einstein’s theory implies that space-time would have a beginning. They developed a theory that provided a set of sufficient conditions for the existence of a singularity, implying that space and time began in a Big Bang event. A singularity is a region of space-time where density of matter becomes infinite and the concept of space and time becomes obsolete. Think of all the matter and energy that exists in the current world, all piled on top of each other. This would not only mean that there is infinite pressure, but also an infinite density. At that singularity, in such an environment, Einstein’s General Theory of Relativity along with any theories that deal with physical laws become inapplicable. The logic behind the presence of a singularity or at least the beginning of the universe can be easily understood when you trace your steps back from the world we live in now. Scientists currently know that the galaxies seem like they’re moving away from us and that in fact space-time itself is expanding in an accelerating rate. This means that when you trace back your steps from our current, accelerating universe to the supposed “beginning of time”, we arrive at a single point, also known as the singularity. From that point, we can assume our universe went through the Big Bang, elements forming from the initially dispersed plasma, elements forming molecules as the universe expanded and everything cooled down to a certain degree. Hawking predicted that a black hole would also have that same singularity within its center.

 

1)    What are Black Holes?


Although, the existence of black holes was proposed long ago and has been developed by a number of scientists, some of which you probably are familiar with such as Isaac Newton and Albert Einstein, it was Hawking who suggested and proved some of the major characteristics of it. Hawking made was how black holes were technically given the wrong name, that they were not entirely black. Black holes were named so because the black hole would suck up all the light by even the nearest star. However, that would’ve been a name solely based on the observable electromagnetic waves. Although it might seem like nothing will be able to escape once it’s past the event horizon and thus there will be nothing, Hawking proves that it isn’t necessarily true. Let’s imagine you are a particle – anti-particle pair falling into the black hole (I honestly don’t know who would ever imagine themselves as a pair of particles, but for the sake of understanding this concept, we will do that), on the edge of the event horizon (a boundary around the black hole where the escape velocity is faster than the speed of light). Virtual particle pairs such as you are constantly being created and annihilated at this high-energy zone. However, if one of your virtual pairs, let’s assume the normal particle is past the event when the anti-particle is still on its way to the event horizon (imagine the event horizon as an extremely thin boundary). Then the normal particle will be pulled into the black hole before it can collide and annihilate with your anti-particle and consequently the anti-particle will be flying off, away from the black hole.

 

Hawking also helped bring cosmology to the masses by writing books such as “A Brief History of Time,” “The Grand Design” and “The Universe in a Nutshell.” His work has been admired by all, the entertainment industry even filming a movie The Theory of Everything starring Eddie Redmayne and Felicity Jones and television networks presenting documentaries such as Into the Universe with Stephen Hawking.

 

Over the course of his life, Hawking has married twice, has had three children and published more than 100 papers attempting and often succeeding to answer mind-boggling questions dealing with the physical forces of our universe. He outlived all of our expectations and certainly is one of the greatest losses the scientific community experienced in a while. His ashes will be interred later this year at London’s Westminster Abbey which houses the remains of Isaac Newton, Charles Darwin, and other renowned scholars.

*General Theory of Relativity: Albert Einstein’s refined version of the Special Relativity Theory. Presents ideas such as gravity as a property of space-time, expanding universe, time-dilation, and gravitational light bending and curvature of space-time.

 

Sources:

 

https://www.youtube.com/watch?v=XDWXNelRsOg

http://www.hawking.org.uk/publications.html

http://www.hawking.org.uk/the-beginning-of-time.html

https://www.nytimes.com/2018/03/31/world/europe/stephen-hawking-funeral-eddie-redmayne.html

https://www.physicsoftheuniverse.com/scientists_hawking.html

https://www.space.com/39988-black-hole-mysteries-stephen-hawking.html

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/hawking.html

http://www.hawking.org.uk/about-stephen.html