Stephen J. Hawking by Rachel Finck
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Stephen J. Hawking by Rachel Finck
Stephen Hawking was born in January of 1942 in Oxford, England. He grew
up near London and was educated at Oxford, from which he received his BA in 1962,
and Cambridge, where he received his doctorate in theoretical physics. Stephen
Hawking is a brilliant and highly productive researcher, and, since 1979, he has
held the Lucasian professorship in mathematics at Cambridge, the very chair once
held by Isaac Newton. Although still relatively young, Hawking is already being
compared to such great intellects as Newton and Albert Einstein. Yet it should
be noted that since the early 1960s he has been the victim of a progressive and
incurable motorneurone disease, ALS, that now confines him to a wheelchair.
This affliction prevents Hawking from reading, writing, or calculating in a
direct and simple way. The bulk of his work, involving studying, publishing,
lecturing, and worldwide travel, is carried on with the help of colleagues,
friends, and his wife. Of his illness, Hawking has said that it has enhanced
his career by giving him the freedom to think about physics and the Universe.
Stephen Hawking has written many essays involving the unified theory,
which is a theory summarizing the entire of the physical world; a theory that
would stand as a complete, consistent theory of the physical interactions that
would describe all possible observations. Our attempts at modeling physical
reality normally consists of two parts: a) A set of local laws that are obeyed
by the various physical quantities, formulated in terms of differential
equations, and b) Sets of boundary conditions that tell us the state of some
regions of the universe at a certain time and what effects propagate into it
subsequently from the rest of the universe. Presently, physicist are still
trying to unify two separate theories to describe everything in the universe.
The two theories are the general theory of relativity and quantum mechanics.
Albert Einstein formulated the general theory of relativity almost
single-handedly in 1915. First, in 1905, he developed the special theory of
relativity, which deals with the concept of people measuring different time
intervals, while moving at different speeds, yet measuring the same speed for
the speed of light, regardless of velocity. In 1915, he developed the general
theory of relativity. This theory dealt with the concept of gravity as a
distortion of space-time, and not just a force within it.
Einstein\'s original equations predicted that the universe was either
expanding or contracting. Einstein\'s equations showed that mass and energy are
always positive, which is why gravity always attracts bodies toward each other.
Space-time is curved back onto itself like the surface of the earth. It was
then theorized that what if matter could curve a region in on itself so much
that it could cut itself off from the rest of the universe. The region would
become what is known as a black hole. Nothing could escape it, although objects
could fall in. To get out, the objects would have to move faster than the speed
of light, and this was not allowed by the general theory of relativity. In 1965,
Hawking along with Roger Penrose proved a number of theorems that showed the
fact that space-time was curved in on itself so that there would be
singularities where space-time had a beginning or an end.
"The fact that Einstein\'s general theory of relativity turned out to
predict singularities led to a crisis in physics. (Hawking)" The equations of
general relativity cannot be defined as a singularity. This means that general
relativity cannot predict how the universe should begin at the big bang. Thus,
it is not a complete theory. It must be paired with quantum mechanics.
In 1905, the photoelectric effect was written about by Einstein, which
he theorized could be explain if light came not in continuously variable amounts,
but in packets of a certain size. A few years earlier, the idea of energy in
quanta had been introduced by Max Planck.
The full implications of the photoelectric effect were not realized
until 1925, when Werner Heisenberg pointed out that it made it impossible to
measure the position of a particle exactly. To see where a particle is, you
have to shine a light on it. As Einstein showed, you had to use at least one
quanta of light. This whole packet of light would disturb the particle and
cause it to move at some speed in some direction different than its state before
the light was shined. In this way, it was theorized that the more accurately
you want to measure the position of the particle, the greater the energy packet
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Black holes, General relativity, Cosmologists, Philosophers of science, Physical cosmology, Quantum mechanics, Quantum gravity, Theoretical physics, Physics, Big Bang, Albert Einstein, Roger Penrose
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