Literature review

Black holes; Discoveries after Discoveries

Presentation of the topic

Black holes are one of the many things in the universe that scientists still have a muddy understanding of. Never discovered until 1780 and predicted by the famous physicist Albert Einstein, black holes were called black hole only in the 1960s. It is only since 2019 that scientists have been able to take clear photos of black holes even though they are millions of kilometers away. Many questions about them have emerged and have never stopped evolving the science of astronomy and astrophysics. The simple question that everyone should ask themselves is '' But what is a black hole in reality? ‘‘Several scientists have already asked themselves the question, and numerous studies have emerged as a result. Some consider them as stars while others consider them just as a region in space-time. The questions remain present because no one was able to see one clearly and precisely. Indeed, the first picture of a black hole was taken by the Telescope Event Horizon and was published only recently. Therefore, many studies tried to prove them as a star with multiple calculations and others as the consequence of the formation of our galaxy.

Presentation of the articles

In his study, Graeme Heald (2018), presented arguments in favor of the fact that black holes could be considered as quark stars by proving them with different calculations based on theories. What he brings new is the fact that black holes can be totally different from what other scientists have said. As previously mentioned, the author came to his arguments through mathematical formulas invented by other scientists like Albert Einstein who were able to make an active contribution in what attracted work on black holes. The author used several methods to support his arguments. Second data analysis was used. In fact, the author was able to provide evidence to his arguments based on popular scientific formulas to bring new data to his stud and analyzed them. Several scientists like the author attempted to observe the black holes. The first part of the study is more based on subject theory. The author tried to define his concepts to improve the understanding of his article. In this section, Graeme Heald (2018) mentions that definitions of these concepts come from recognized scientists. In the second part of his article, the author prefers to show his calculations based on the theory above. However, he does not just demonstrate them. Indeed, he makes sure to support all his formulas with a good paragraph explaining the parameters of his equations. The article does not contain a message, but rather the response to his proposal, to his hypothesis that black holes could be considered as quark stars.

Grib, A., & Pavlov, Y. (2017) rather decided to approach the subject from a different angle. Instead of talking about black holes in general, they decided to choose a specific aspect of them and then do a vigorous analysis. As in article 1, Graeme Heald (2018), the authors demonstrated, using mathematical calculations, their theory of the negative energy that particles can possess in black holes. They used the method of second data analysis but did not support them with many theories. Instead, it is a neutral article that merely presents data. Compared to other conventional scientific articles where sections are separated with Introduction, Methods, Discussion, and Conclusion, this article is rather separated into numbered chapters.  Each chapter presents something different. Even though the chapters have a common link, arriving at the proposal made by the authors in the introduction, each section can bring something different always supported with mathematical and physical calculations. To make its discussion, the authors decided to do so throughout their study. Thus, no observations were made, but rather the collection of data to analyze them. As in the previous article, there is no real message. The authors do not even end their study with a conclusion, but rather with calculations that prove their original proposal.

In the last article, Keith W. Moored, Jr. (2018) decides to talk about black holes as one of the sources of the formation of our galaxy and their roles in this perspective. The author is proposing that black holes recycle dark matter from space and that this would be a factor in the formation of our galaxy. He begins his article by defining all the essential concepts to know and that are directly related to his question. He takes at least half a page to ensure that readers are put into context by explaining the meaning of these terms. Subsequently, instead of presenting only calculations, the author chooses to explain throughout his article, why black holes and decoding cycles of material recycling would be the basis of the formation of our galaxy. However, in two appendices he presents some calculations to support his remarks and explanations. In his conclusion, the author decides to end by saying clearly that his initial proposal was correct, and that this theory is a continuation of the one on the Big Bang. So, he ends up with an opening.