2. Stephen Hawking is one of the most influential
physicist of our time. He was born January 8, 1942.
Stephen is a British author and theoretical physicist with
some of his most famous and important work on
theorems of gravitational singularities with Roger
Penrose and on his theoretical prediction that black
holes should emit radiation. This radiation is now often
called Hawking radiation. Hawking is also famous for
several best seller books on the subject of Physics. These
books include A Brief History of Time, Black Holes and
Baby Universes, and one of his most recent books The
Grand Design which was published in 2010.
As you can see from the photo on the
right, Hawking is confined to a wheelchair and is almost
completely paralyzed. The reason he is like this is
because of a motor neuron disease related to
amyotrophic lateral sclerosis according to Wikipedia. Stephen Hawking
This disease has progressed over time since he was first
diagnosed with it about 1962. Now he can only talk with
the help of a speech generation device.
3. Stephen Hawking was born to Isobel and Frank Hawking. At the age of
11 he attended St. Albans School, Hertfordshire and after that he studied at
University College, Oxford. Here Hawking applied to study natural sciences that
had a emphasis on physics. After getting his Bachelors degree at Oxford, he went
on to study at Trinity Hall, Cambridge. It was here that he first learned of his
illness, but he kept on working and received his doctorate in 1966.
During the mid to late 1970s, Hawking entered a period of increasing
popularity and success. He was starting to appear in television documentaries and
in 1979 he became the Lucasian Professor of Mathematics at the University of
Cambridge. This chair was founded in 1663 with some money that was left in the
will of Reverend Henry Lucas who had been a member of Parliament for the
University. The chair was first held by Isaac Barrow and then in 1669 by Sir
Isaac Newton. In 1997, Stephen made a public scientific bet with Kip Thorne and
John Preskill of Caltech. This bet was about the black hole information paradox. In
2004 Stephen announced defeat and gave John Preskill a copy of a baseball
encyclopedia as a reward.
Hawking has been awarded many prizes for his many contributions to
the sciences. These awards include the Albert Einstein Medal, Commander of the
Order of the British Empire, member of the Pontifical Academy of Sciences, and in
2009 he was awarded the Presidential Medal of Freedom, which is the highest
civilian honor in the United States. The most famous contribution that Hawking
has made was the discovery of the sometimes named Hawking radiation.
4. Black holes
When most people think of a black hole
they think of quite literally a “black hole”
just sitting there in space, but black holes
are some of the most fascinating objects
in the universe.
Black holes are remnants of super massive stars
that have gone supernova. These black holes
have such high amounts of gravitational forces
drawing into them that not even light can escape
their grasp.
Stephen Hawking has been a major
contributor of interesting theorems and
theories to the subject of black holes and
one of his most famous ones is about Black
hole radiation. Sometimes called Hawking
Radiation .
5. Hawking Radiation
Hawking Radiation is a form of radiation that comes from black
holes. This radiation is also called black hole evaporation. This
evaporation makes it impossible for microscopic black holes to
exist.
How Hawking Radiation works is that there are these
particle-antiparticle pairs called virtual particles popping in and
out of existence all around us. What is an antiparticle you might
ask, well an antiparticle has the opposite electric charge than its
counterpart. So if you had a negative electron its antiparticle
would be the positive positron. When an antiparticle and a
regular particle of the same type meet they annihilate each
other and release all of their mass energy.
Now on to virtual particles. Virtual particles are
The picture above shows the particle-antiparticle pairs particle-antiparticle pairs that borrow their energy from the
next to a black hole’s event horizon. surrounding space and pop into existence. They then after a very
short interval annihilate each other and release their borrowed
energy back into space. At least this is what normally happens.
Sometimes this pair of particles appear right next to the event
horizon of a black hole. When this happens one of the
particles, the antiparticle, falls into the black hole while the other
particle escapes into space, a free particle. The other particle
goes into the black hole and annihilates with another particle
decreasing the mass of the black hole. This evaporation is
enough to totally consume microscopic black holes making it
impossible for them to exist.
This shows a particle-antiparticle pair annihilating each other.
