You are on a spaceship, cruising in the midst of space. All of a sudden, there is a disturbance. The spaceship starts accelerating toward a point. You quickly turn the engines on to full power in reverse, trying to escape the mysterious gravitational pull on the ship, but to no avail. You are being sucked into a black hole, something you never had believed in. And to think, all this could have been prevented had you just believed… Scientists have long searched for evidence of the existence of black holes. The evidence was hard to find, since black holes don’t let light escape them, and thus they cannot be directly observed. However, their existence has been inferred through their effects on their surroundings. There is one thing black holes can’t hide - their noticeable effect on the gravitational field. Contrary to some who think black holes are only science fiction, black holes really do exist.
First of all, scientists have observed large clouds of cosmic dust, stars, and other matter orbiting an invisible massive object at extremely high speeds (The Universe). Some of those objects get closer and closer to the center of rotation until they disappear from view. Physicists have modeled this phenomenon and came to the conclusion that the most likely explanation is that the matter is getting sucked inside a black hole. According to Roeland Van Der Marel, these observations and their theoretical explanation are based on Einstein’s general theory of relativity, which predicted the existence of black holes back in 1915. Furthermore, stars and other known galactic objects do not have a high enough gravitational pull to make matter orbit them at such high speeds, and they do reflect light, so if the mysterious object in the center of rotation were a regular star or a dust cloud the scientists would have been able to see it (Roeland Van Der Marel). So overall, the only phenomenon that could be causing the matter’s perplexing behavior is a black hole.
Scientists have also observed gamma rays streaming from the points where the matter disappears under the invisible gravitational pull (The Universe). According to NASA, the types of cosmic objects that can produce high energy gamma rays include remains of supernovas, quasars, neutron stars, and black holes. In the case described in The Universe, there are no visible objects such as stars, supernovas, quasars, or neutron stars in the vicinity. The remaining plausible explanation is that the gamma rays are emitted due to the extremely rapid acceleration of matter falling into the singularity of a black hole.
The most direct evidence of the existence of black holes is in the relationship between the mass and size of massive objects lying at the center of many galaxies, including our very own Milky Way galaxy. By dividing the mass of an object at the center of our galaxy by its size, scientists have calculated the implied density, which turned out to be high enough to produce a black hole. As discovered by Einstein in his general theory of relativity, once the density of matter exceeds some critical value, any particle that gets close enough will be sucked in and won’t be able to escape even if it moves with the speed of light. This is how black holes appear (The Universe). Astronomical observations of cosmic matter’s behavior near the center of our galaxy and several other galaxies are precisely consistent with the phenomena predicted to occur near black holes.
Despite all the evidence, black holes may actually not exist. According to Stephen J. Crothers, even though it may seem as though black holes exist, the idea of black holes goes against the theory of quantum physics, and therefore it is impossible for black holes to exist. If quantum physics had more evidence supporting it, that would be a valid concern. However, quantum physics is itself an unproven theory, with substantially less evidence for it than for the existence of black holes. So actually, the theory of quantum physics might itself be wrong, while the theory that black holes exist looks perfectly valid.
Black holes have a profound effect on everything in the universe, and there is ample evidence for their existence. First, matter has been seen orbiting invisible objects at high speeds, eventually getting sucked into a point, nowhere to be seen. Second, high-energy gamma rays have been observed radiating from those points, as cosmic matter falls into a gravitational singularity of black holes. Finally, the densities of massive objects at galaxy centers lie above the critical level where the space warps and a black hole appears. All these facts indisputably point to only one thing: the existence of black holes. Even Einstein would agree.
Works Cited
1. The Universe, Black Holes Episode, A&E Television Networks, 2011, Movie Episode
2. "HubbleSite: Black Holes: Gravity's Relentless Pull Interactive: Encyclopedia."HubbleSite: Black Holes: Gravity's Relentless Pull. Roeland Van Der Marel, n.d. Web. 6 Mar. 2014. <http://hubblesite.org/explore_astronomy/black_holes/encyclopedia.html>.
3. Stephen J. Crothers, person
4. "Gamma-rays." Gamma-rays. NASA, n.d. Web. 29 Apr. 2014. <http://science.hq.nasa.gov/kids/imagers/ems/gamma.html>.
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