This book review will summarize A Brief History of Time. (The Updated and Expanded Tenth Anniversary Edition) which is a 226-page book written by Hawking, Stephen, W. on September 1998. This book was published by the Bantom Books Publishing Company, located in New York City, New York. This book was copyrighted in 1988 and 1996. The genre of this book is popular science. This book contains information on astronomy, cosmology, astrophysics, and quantum theories. It elaborates in great detail about conceptual lessons on physics, then it uses this basis to construct important scientific questions and how they were tackled. Each lesson is backed up by numerous theories, facts, and visual diagrams. This review will analyze this book thoroughly. This book includes conceptual lessons about topics in cosmology, including complex topics such as relativity, quantum mechanics, particle physics and phenomena such as the big bang and black holes. This book gives history and context about the search for a unified theory of relativity and quantum mechanics. This piece of scientific literature also includes a detailed qualitative examination of historical and contemporary views on the nature of time and the universe. Stephen Hawking made this book to inform others about cosmology and further related subjects to help spread interest in these areas, a key point reflected by his foreword which described the intentions of the book.In chapter three, The Expanding Universe, we are given evidence and reason on why the universe is expanding. Discussed is the Doppler shift, a phenomenon that occurs when something is moving towards (blue shifts) or away (red-shifts) from something else. By studying blue and red shifting through wavelengths of visible light, Edwin Hubble discovered many stars were red shifting. Hawking describes our expanding universe through this lens. Another point explained, is the observable ever-increasing distance between the Earth and certain stars. This increasing space between Earth and far away stars, led astronomers to infer that galaxies are moving away from this galaxy. Using these basic observations, Stephen Hawking concludes that our universe is no longer a static one, and shows us that it was never stationary in the first place. Rather than our universe being static, the galaxies in our universe are moving apart from one another; In other words, the galaxies and our universe are also expanding. In chapter 6, Black holes, is one of the main topics covered by this book. Black holes were significant works researched by Hawking, and he explains that black holes hold significant clues about our universe. This chapter focusses on the foundation of black holes, and star cycles including how a black hole may be a phase of a star’s life. He first explains the star cycle in great detail. Let us briefly summarize the points he covers. Firstly, a star is formed from huge amounts of hydrogen collapsing on itself due to gravitational attraction. Then atoms collide and contract, colliding exponentially faster. As a result, heat is released, increasing the pressure of the gas until there is a balance in gravitational attraction; which will stabilize the star. Eventually, the star will run out of its Hydrogen fuels, causing the star to cool off and contract After Hawkings has established a rudimentary knowledge about stars, he delves into possible futures of a star. Basically, a star’s fate depends on Chandrasekhar’s limit which explains that if a star is a certain mass. A star will either become a white dwarf, a neutron star or, if it’s heavy enough and gravity collapses within it, it’ll become a black hole! The chapter then explains that black holes are stars that have collapsed into one very small point called a singularity. Hawking also explains that they have a very strong gravitational force, and are able to pull things. This includes pulling light and stars, inwards to their centers. We then learn that black holes are almost impossible to locate because they do not let light out. However, they can be seen by telescopes when they suck in other stars, because they emit x-rays. Chapter 8, The Origin and Fate Of The Universe, is about how the origin of our universe formed and how it may end. The theory that the big bang was the main reason for the formation of our universe is the most accepted theory among scientists. Hawking then explains the hot big bang model. To summarize this model, we need to presume or understand that the universe started out infinitely hot. When the temperature started to trend towards the low end, the electrons and nuclei began to overcome the general electromagnetic attraction. This led to the formation of atoms. After the universe started to expand, various regions started to expand at different rates due to the difference of densities. At one point, regions started to slow down and stop, causing a recollapse of regions. This gravitational pull began to take in matter from outside of the regions of the universe, which led to the rotation and spin that would balance the attraction of gravity. Eventually, gases like hydrogen and helium would form from the many atoms colliding. This allows for the formation of multiple celestial bodies over time such as very own planet. Hawking then explains some possible fates that the universe may have. One possible outcome or future is the “Big Crunch” singularity which is what is predicted by Einstein’s general theory of relativity. To explain the Big crunch in basic terminology, it means that the universe will recollapse on itself. Another option is the that our universe will end at a singularity inside a black hole. Any mass that would enter this hole would be destroyed at the singularity, and the gravitational effect of the mass would only be felt by outside regions before they also enter into this hole. However, These two theories are overshadowed by the most popular theory of the universe’s fate. This theory is that the universe will continue to expand forever. This theory is the most accepted theory because the present evidence proves that even with the mass of dark matter and every star in every galaxy, the expansion of the universe cannot be halted The general conclusions of this book can be seen in both chapter one, Our Picture of the Universe and chapter twelve, Conclusion. A human’s desire for knowledge of the world in which they exist in is one of the main themes that Stephen Hawking believes this book concludes. Humans are inclined to know the answer to the many questions that the universe has brought. These questions gave birth to theories and new perspectives about our universe. As more knowledge is obtained, humans have learned that this universe inhabits a set of laws that govern the nature of the universe including things that can and cannot happen for certain reasons.This knowledge and the ability to use the previous knowledge to craft out representations and understandings separates our unique race from others. Although, there are many gaps we cannot explain. This is where religion takes it’s place in history, It gives the feeling of having an answer for our many questions. Perhaps the biggest question about the universe is why it exists and why humans exist; Stephen Hawking states this in his Conclusion, saying that by answering this question, humans can truly know the mind of God. I believe Stephen Hawking achieved his purpose in this book, which is to spread information to general people about cosmology, astronomy, and astrophysics. He sparked many people’s interest and curiosity about our great universe. The success of the book is one of the reflections of the achievement Hawking had accomplished. Not only does this book have 9 million copies sold worldwide but also as stated, “It was in the London Sunday Times best-seller list for 237 weeks.”(p. 9) The book’s popularity has shown that this book has been well received and has spread the important information conveyed by the book to a worldwide audience. This is one of the exact reasons why Hawking wrote this book, to spread information about cosmology, astronomy, and astrophysics to the general nontechnical people of the world. I think Hawking had a very effective writing strategy, especially for explaining the complex concepts nested in numerous chapters. A very observable style that Hawking implements is starting out the chapter with a clear simple introduction to the concept that would be discussed. He then would use this simple introduction to build up to details of the complex concept A marvelous example can be seen in the beginning of chapter five, Elementary particles. The beginning of the chapter starts out with something that is basic, “Aristotle believed that all the matter in the universe was made up four elements basic elements–earth, air, fire, and water”(p. 76). Hawkings then develops his point by sharing history about how these divisions of the content in the universe had become more complex. He backs these explanations by giving us previous experiments in history and then introduces quarks. It was much easier to understand quarks after Hawking’s had given us an introduction to matter and divisions of matter. After explaining the experiments of Physicist Murray Gell-man, he states the properties of quarks in a very simple manner. This section is a good example to share, “There are a number of different varieties of quarks: there are six ‘flavors,’ which we call up, down, strange, charmed bottom and top.”( p. 79) This section made it very easy for me to follow up on the later chapters. Hawking’s great style is implemented throughout the whole book, which makes it very effective. There are many strengths in this book. One strength of this book is the incorporation of visuals and diagrams to accompany the explanation of advanced topics. One example is “(An event, in this sense, is something that takes place at a single point in space, at a specified point in time.) This idea is shown in Fig. 2.1 .” ( p. 34) At first, I had a little trouble visualizing space as a system that has various two-dimensional points of time. Then I looked at the easy to understand diagram which made my understanding of the topic much more clear. I really enjoyed the visuals in the books. Another strength in the book is the use of analogies. An example of this is “It means that the boundary of the black hole, the event horizon, is formed by the light rays that just fail to escape from the black hole, hovering forever just on the edge (Fig, 7.1). It is a bit like running away from the police and just managing to keep one step ahead but not being able to get clear away!” (p.115) I have to say that when I read this I could clearly understand how the event horizon was formed partly because of the analogy. The analogies Hawking incorporates really enhance the overall mood of the book, and they also helped me understand the topics better.There are a few weaknesses of the book. One weakness is that some chapters are sometimes hard to follow, although most chapters are clear as noted by the observations of Hawking’s style. The thing is if you don’t understand a topic, it will become a weight that tends to drag you down from understanding other chapters. The book sometimes expects you to understand the principals, or you’re not going to benefit from the latter of the chapters. One example is “Einstein’s general theory of relativity, on its own, predicted that space-time began at the big bang singularity and would come to an end either at the big crunch singularity (if the whole universe recollapsed), or at a singularity inside a black hole (if a local region such as a star, were to collapse)” (p.130). Without understanding Einstein’s general theory of relativity, people would not be able to understand anything else Hawking is saying in the beginning of this chapter. The Brief History of Time may be brief, but it may still be too difficult for an average layman to read.Stephen Hawking, the author of A Brief History of Time, in my opinion, seems to be very qualified to write such a book. Hawking is the Lucasian Professor of Mathematics and Director of Research at the Centre for Theoretical Cosmology at the University of Cambridge. Hawkings also has numerous years of experience, which further qualifies him. In the “About the Author” section, it states that Hawking was a professor at the University of Cambridge for thirty years, and has been recipient of numerous awards. He is also known for his publications as a theoretical physicist and cosmologist. All of the qualifications stated above more than enough show that Hawking is qualified to write A Brief History of Time.I agree with Stephen Hawking’s conclusions of how as humans we try to obtain knowledge for our curiosity and interest. Our existence is driven by our ability to find answers to questions. A quote that reflects Hawking’s conclusion is in the early beginning of this book, Stephen Hawking says, “Today we still yearn to know why we are here and where we came from. Humanity’s deepest desire for knowledge is justification enough for our continuing quest. And our goal is nothing less than a complete description of the universe we live in.” (p. 14) I agree with Stephen Hawking on the validity of the conclusion because as humans we do want to make sense of the things around us. I still have questions about our universe, and his book has inspired me to research these questions.Overall, I had a thrill reading this book! It was very interesting and when it starts discussing the extreme technicals, I would watch a video or read an article to further my understanding of what was being presented. I especially liked the mood of the book, which was highlighted by the humorous and intriguing tone that was displayed by Hawking’s writing. I especially loved when he used analogies and interesting stories such as the Twin paradox. It gave me insight and a new lens to perceive this large world and changed my approach in questioning and curiosity. An interesting note is that after reading this book, I felt very insignificant relative to our universe. I would definitely recommend this book to anyone in high school, or even older. Although the technicals may be a drawback, you can still pick up general conclusions drawn by each chapter. Even if you don’t understand it that much, there is still much to learn about particles, about time, space light and all of their relations. This book certainly raised my interest in science and in astrology, and I can guarantee anyone who reads this book will have a more intriguing perspective of our universe.