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Black Holes
By Randy Guardado
Physics 1010
Howard Demars
Salt Lake Community College
December 8th, 2016
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Black Holes
The black hole was originally brought into question as a question itself. What if there was
a body that was so massive that even light could not escape its reach and vicinity? This is only
one of many phenomenon that is out in space and has become one of the most thought about
questions due to its popularity in fictional writing and the sheer thought of having such a
powerful and dangerous entity somewhere out there in our universe. Although black holes
present themselves as one of the most thought about phenomena and theories in astrology at the
moment, they are one of the least researched ones as well, due to the rarity and dangerousness of
one.
From what is currently theorized and known about black holes, a black hole is “a place in
space where gravity pulls so much that even light cannot get out. The gravity is so strong
because matter has been squeezed into a tiny space.” [2] The cause for the gravity in a black hole
being so strong is because it is incredibly dense, and its ability to “suck in” light is also the other
reason for its name, as you cannot see a black hole without a special device because of the
absence of light. The gravitational pressure is so strong that anyone sucked in could be just
compressed down to nothingness from the density of the black hole, but many new theories have
been appearing such as interpretations in the film “Interstellar” of wormholes to other universes
[5] or going so fast because of quantum mechanics that you hit a firewall and burn up inside the
black hole. [6]
While the concept of there being an entity whose surface velocity on such a dense object
in space would exceed even the speed of light by John Mitchel in 1784 existed, it was not until
Einstein’s Theory of Relativity that this idea was able to be expanded upon. General relativity
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explains laws of gravitation and its effect on space-time, including light, this helped form a
plausible reason for light to be non-existent in this dense object in space — the gravity would be
so immense that the light would warp and no longer be in the visible spectrum. One German
scientist — Karl Schwarzchild — was able to make a mathematical solution that used the theory
of relativity in order to describe an object around the 1920’s. This equation, named the
“Schawarzchild Metric,” helped discover that there might be a singularity at a center of a black
hole. Additionally, further research from Subrahmanyan Chandrasekhar in the 1930’s discovered
that a “star having a mass more than 1.44 times that of the Sun … [collapses and] becomes a
neutron star.” [10] The neutron star is a result of the ensuing supernova explosion from residual
gases from the star’s reactions, and since a neutron star is so dense already, if a star were to be
even more than 1.44 times the mass of the sun it would result in a black hole instead of a white
dwarf or neutron star.
Black holes currently have three different categories of sizes, those being stellar,
intermediate-mass, and supermassive, with a supermassive black hole being up to approximately
0.001 to 400 astronomical units large. It’s speculated as well that most large galaxies house a
black hole in the center of the, the bigger the galaxy the higher the odds of it being a
supermassive black hole. Its place in the universe could be a concern, but Earth is presently safe
from any such threat, as there is no black hole close enough to the solar system to cause
gravitational pull on Earth, and the sun does not have the mass necessary to become a black hole.
However, theories have been developed on what would occur if a person were to enter in range
of a black hole.
If a person were to enter the range of a black hole and be pulled into it, the immense
gravity difference would stretch a person as the gravitational difference between a person’s head
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and a person’s feet would be enormous. Outside of the range of a black hole, if another person
were to witness the first individual being sucked into the black hole, they would see their
movement slowly slow until they eventually simply stop, while the individual inside will
perceive time to flow normally. This is due to the immense gravity distorting space-time, giving
two different frames of reference which are perceived as different, which is something very
interesting for theoretical physicists. [4] In addition, due to gravity distorting space-time in a
black hole, the curvature also warps, giving the black hole strange properties. Black holes
contain something called an “event horizon,” a velocity required to escape a black hole because
it matches the speed of light, however since general relativity states that nothing is faster than
light, it means “nothing that enters a black hole can get out or can be observed from outside the
event horizon. Likewise, any radiation generated inside the horizon can never escape beyond it.”
Event horizons also serve to explain how red shift will cause distant galaxies to continue to leave
our view since light cannot catch up, therefore after a galaxy becomes out of view, it will
eventually be undiscoverable, a point of no return.
I do not think there is any way to harness black holes as some sort of benefit to humanity,
and anyways, due to the relative danger of being in proximity of one, I do not believe we will
have an opportunity to view the actual effects of a black hole. The most recent discovery with
plausible evidence of a black hole has been in 2005 when the Laser Interferometer GravitationalWave Observatory (LIGO) detected a gravitational wave that was “4 times the Schwarzchild
radius corresponding to the inferred masses,” [12] concluding that the two objects must have
been extremely compact, possibly a black hole.
In conclusion, black holes have been theorized about for a few centuries now, and
advancements in physical sciences and astrophysics are helping paint a clearer picture for what
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black holes can be, and how they can be used as analogs for finding more about our world, such
as the event horizon. Lots of media portray different theories of black holes as either spectacular
or horrifying things, such as wormholes being used as a method of transportation in the universe
or having worlds be swallowed by the gravitational pull of a black hole, respectively. It is
disappointing that black holes cannot be further researched on besides quantitate values and
speculation, but with drive from the scientific community and new developments always being
found such as event horizons, disproving of other theories possibly, and using hyper-sensitive
equipment to find concrete proof of them in the galaxy, it is very viable that humanity might in
fact see one through an observatory in our lifetime.
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Bibliography
1. Van Der Marel, Roeland. "HubbleSite: Black Holes: Gravity's Relentless Pull Interactive:
Encyclopedia." Hubble, n.d. Web.
2. Dunbar, Brian. "What Is a Black Hole?" NASA, 30 Sept. 2008. Web.
3. Jones, Andrew Zimmerman. "What Exactly Is a Black Hole?" About.com. N.p., 01 Sept.
2016. Web.
4. Redd, Nola Taylor. "Black Holes: Facts." Space.com. N.p., 09 Apr. 2015. Web.
5. Wall, Mike. "The Science of 'Interstellar': Black Holes, Wormholes and Space Travel."
Space.com. N.p., 10 Nov. 2014. Web.
6. Merali, Zeeya. "Astrophysics: Fire in the Hole!" Nature.com. Macmillan Publishers, 3
Apr. 2013. Web.
7. "The Origins of the Universe: Black Holes." Centre for Theoretical Cosmology: The
Origins of the Universe. University of Cambridge, n.d. Web.
8. Mitchel, John. "On the Means of Discovering the Distance, Magnitude, &c. of the Fixed
Stars… By the Rev. John Michell, B. D. F. R. S. In a Letter to Henry Cavendish, Esq. F.
R. S. and A. S”. Royal Society Publishing, 1 Jan. 1784.
9. Matsin, Luke. "Karl Schwarzschild." The Physics of the Universe. N.p., 2009. Web.
10. "Subrahmanyan Chandrasekhar." Encyclopedia Britannica Online. Encyclopedia
Britannica, 5 Apr. 2016. Web.
11. "Event Horizon." Encyclopedia Britannica Online. Encyclopedia Britannica, 20 Feb. 2009.
Web.
12. Overbye, Dennis. "Gravitational Waves Detected, Confirming Einstein’s Theory." The
New York Times. The New York Times, 11 Feb. 2016. Web.