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_Black Holes _
By: Christoffer Sundy
Black Holes If theories of their existence are true, black holes are the most
powerful force in the known physical universe. Many people are familiar with
the term black hole, but few people actually know anything about them. A black
hole forms as a result of a massive star running out of fuel to burn
(Chaisson, 193). Once the star is no longer exerting outward force by burning
off gases, it begins to collapse under it's own intense, inward gravity
(Chaisson, 193). It is like slowly letting the air out of a balloon. Once the
star is compacted to a certain size, while it's mass, or weight, remains the
same, it's gravity becomes so powerful that nothing can escape it (Hawking,
87). This critical size to weight ratio is known as the Schwarzchild Radius
(Hawking, 87). Once a black hole is created in this way, an invisible area, or
line around it exists. If any object crosses this line, it can no longer
escape the gravitational force of the black hole (Hawking, 87). This line is
called the event horizon (Hawking, 87). If black holes are proven to exist,
beyond theoretical physics, then they would probably be a very common anomaly
in this universe. In 1915, Albert Einstein put forth the first real
proposition of such an anomaly in his "Theory of Relativity" (Bunn, Black
Holes FAQ). In the 1930s, three physicists, doctors Volkoff, Snyder and
Oppenheimer, were able to prove the validity of black holes mathematically.
Since then, black holes have become a very important and integral part of
science and the over all understanding of the universe. It has been proven,
mathematically, that black holes have infinite, gravity based, escape
velocities and an immense effect on light, time and even the very fabric of
space. All bodies in space have gravity. According to Einstein's "Theory of
Relativity", this is because bodies with a large mass, or weight, actually
warp space (Chaisson, 77). For example, if a two dimensional sheet of cloth,
stretched and suspended at four corners, represents space, and a bowling ball
is placed in the center, the sheet will warp downward. If a golf ball is then
set at the edge of the sheet and allowed to move freely it will be attracted
toward the bowling ball, unless the golf ball is traveling at a speed great
enough to not be effected by the curve. This critical speed is known as an
escape velocity. This is the speed at which an object must travel to escape a
body's gravitational force (Chaisson, 77). If a body is compacted, such that
it's weight stays the same but it's radius, or size, becomes smaller, it's
escape velocity increases in parallel (Chaisson, 196). The simple formula for
this, in physics, states that a body's escape velocity is equal to the square
root of it's mass, divided by it's radius (Chaisson, 77). For example, if a
body's mass is two-hundred, and it's size is twelve and one half, the escape
velocity would be four. If the size of the same body is reduced to two, while
it's mass remained at two-hundred, the escape velocity increases to ten. Since
a black hole's size is always decreasing and it's weight is always the same,
the escape velocity is infinite (Chaisson, 195). This means that nothing can
escape a black hole past the event horizon, not even light. Light is made up
of waves and particles. It was discovered, in 1676, by Danish astronomer, Ole
Christenson, that light travels at a very high, but finite speed (Hawking,
18). These properties of light govern that it must be subject to forces of
nature, such as gravity. Light travels at such a high speed that it is not
observably effected by gravity, unless that gravity is very strong. A black
hole's gravity is powerful enough to trap light because it's escape velocity,
being infinite, exceeds the speed of light (Hawking, 82). This is why a black
hole is black. Once light crosses the event horizon it is drawn into the hole
in space. Although the light is still hitting objects, it is not able to
bounce off to indicate their existence to an observer, therefor the black hole
appears as a void in space. Closing in on the edge of the event horizon, light
travels back to an observer at a slower and slower rate, until it finally
becomes invisible. This is due to heavy gravity and the effect that a black
hole has on time (Bunn, Black Holes FAQ). According to Einstein's "General
Theory of Relativity", time is not a constant (Hawking, 86). Time is relative
to an observer and his or her environment (Hawking, 86). It has been proven
that time moves slower at higher speeds (Hawking, 86). An experiment was
conducted in which two synchronized atomic clocks were used. One was placed in
a jet and flown around the Earth at three times the speed of sound, while the
other was left stationary, on the ground (Hawking, 22). When the jet landed
and the clocks were compared, the one in the jet displayed an earlier time.
This leads to the reasoning that time is just as volatile as light or dirt. In
cosmology, a singularity is an event or point that has a future or a past, but
not both (Hawking, 49). In human life, death would be considered a
singularity. A black hole is also considered a singularity. If an object
crosses the event horizon of a black hole, it relatively ceases to exist, it
has no future (Hawking, 88). Absolutely nothing in the known universe can
survive in or escape from a black hole, so it can be said logically that time
is stopped within the event horizon. The only way for an object to escape this
fate would be for a strange anomaly to occur in the fabric of space, caused by
a theoretically different type of black hole. If the mathematics that describe
a black hole are reversed, the outcome is an object called a white hole (Bunn,
Black Holes FAQ). As the complete opposite of a black hole, a white hole is an
object into which nothing can fall and objects are only spit out (Bunn, Black
Holes FAQ). At this point, white holes are strictly theory. Their existence is
highly improbable. If certain properties, such as motion or a positive or
negative charge are applied to a black hole, then the possibility of a white
hole forming within the event horizon arises (Bunn, Black Holes FAQ). This
leads to an even more improbable occurrence called a wormhole (Bunn, Black
Holes FAQ). In theory, a wormhole would truly be a tear in the fabric of
space. Since time essentially has no effect on a black or white hole, if an
object were to fall into a worm hole, it could conceivably be spit out
anywhere in time or space(Bunn, Black Holes FAQ). If an object falls into a
black hole, which has undergone the transformation into a wormhole, it could
probably avoid hitting the singularity (Bunn, Black Holes FAQ). Therefor it
would not be turned into spaghetti and compacted to the size of a base
particle. Instead, it would follow the closest thing to a straight line that
it could find, which would be to slip completely through the wormhole (Bunn,
Black Holes FAQ). It sounds impossible, but it looks good on paper. If
wormholes could exist, according to calculations, they would be highly
unstable (Bunn, Black Holes FAQ). If anything were to disturb it, like an
object passing through it, it would likely collapse (Bunn, Black Holes FAQ).
Though the equations are valid, wormholes most assuredly do not exist. If they
did it would probably send shivers up the science fiction community's spine.
In the book, Relatively Speaking, the Author, Eric Chaisson says, "The world
of science is littered with mathematically elegant theories that apparently
have no basis in reality" (nasa). Although black holes have not been precisely
proven to exist, there is strong evidence, in the observable universe, that
they do. Black holes are very important to the world of cosmology. They allow
for the study of common particles under very uncommon environmental variables.
Scientists have vastly increased their knowledge of the universe and the
properties of matter through the study of a black holes effects on light, time
and the fabric of the space. Afterall, Black Holes may contain the secrets of
mankinds Destiny.
Word Count: 1410
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