The Grand Design By Stephen Hawking

The Book Cover

Stephen Hawking the Author

This book is a great book if you  want to get a overview of our cosmos. It goes over things like string theory quantum theory and the future of our planet. The first chapter goes over basically an overview of our book. I really like Stephen Hawkings writing style because it is easy to  understand yet incredibly interesting. He also makes you want to delve deeper into the subjects he talks about like string theory and quantum theory. It is also a very slim book and I wish in order to make this book even easier to understand he could expand more on some of the more complex topics. I also think that this book is a very good starting place for someone who wants to get started in physics. Quantum theory is basically the theory that electrons and such are almost everywhere at the same time. This books talks extensively about that. Something else it talks about that I wish it would talk about a little bit more is the theory of relativity. This I did not understand as well as I wanted to be able to. Stephen Hawking the author is an amazing person actually he has been diagnosed with ALS. He has been very revolutionary in the world of physics. In conclusion if you are interested in getting into the world of physics and are very interested in this then this is a great place to start. All in all the Grand Design amazingly describes our cosmos and the future and the past. It also discribes how it was formed. Something that I found very interesting was how he explained the history of the people on Earth and how some of the inhabitants were quite advanced in there thinking of the cosmos. Although there were some who had rather far fetched beliefs. This book is amazing if you want to learn anything and everything about whats outside of our world.

The Theory of Everything

A Briefer History of Time by Stephen Hawking

Book Name: A Briefer History of Time
Author: Stephen Hawking

Finding answers to how the universe works has been the focus of scientists for millennia. In the book A Briefer History of Time, world-renowned theoretical physicist Stephen Hawking searches for a single,  complete theory of physics that explains everything in the universe.

In the book, Stephen Hawking stops along the way to introduce us to the great discoveries of time, those including the concept of curved space, the expanding universe, dark matter, black holes, the Big Bang, wormholes, and more.  In the process he clarifies and explains gravity, relativity, and quantum mechanics. He covers amazing discoveries regarding the nature and size of the known universe and discusses important observations based on our effort to peer into distant galaxies. What a journey, done with humor (we learn, for example, how "Isaac Newton was not a pleasant man"), and Stephen Hawking does it "Briefer" that his prior "Brief" history.

Arriving at a complete theory of everything, we learn, requires an understanding of smaller theories, which when pieced together, explain the magic of the universe.  These component theories, though smaller than the whole, are each extraordinarily significant in their own right. Among these, are the Doppler effect, the theory of relativity, and time travel.

Everyone has heard of Einstein's general theory of relativity, but Hawking puts it into context for the reader. This theory explains that gravity, the special force that keeps our feet on the ground, exists because   "space-time" is curved.  Hawking clears-up many misconceptions. For example, the earth does not move in a curved orbit because of gravity; rather, the earth moves in a curved orbit because it follows "the nearest thing to a straight path in curved space". This is called a geodesic. A geodesic can be understood as the shortest path between two places. A good example of a geodesic is when flying to Hong Kong from New York City, you wouldn't travel around the earth; instead, the pilot would travel towards the North Pole and down to Hong Kong because the Earth is a sphere.

The Doppler effect shown by the wailing sirens of a police car.

Hawking also clarifies the Doppler effect. One example of the Doppler effect is when a train honks its horn as it passes by. At first, the horn sounds higher pitched and then, as it passes, the pitch gets lower. As the train approaches, the distance between the wave crest or wavelengths grows increasingly smaller.  The smaller the wave crest, the more sound waves we hear, causing a high pitched sound. Afterwards, when the train is moving away, as Hawking explains, "the wavelength will be greater and the waves will reach our ear with a lower pitch".

A diagram of a wormhole.

Near the end of the book, another nearly incredible theory emerges. Hawking proposes that time travel is theoretically possible (but, don't get your hopes too high because you will need to travel faster than the speed of light, as I explain later). How would this work?  As Hawking explains: suppose there an event on Earth, event A, and event B is an event on Proxima Centauri (the closest star to Earth besides the sun, which is approximately 4 light years away). Suppose that event B happened a year later according to Earth's time. Since the two bodies in space are a few light years apart, and because A happens before B, you would have to travel faster than light to get to B from A. Then, according to the book, "to an observer on Proxima Centauri moving away from the Earth at nearly the speed of light, it would appear that the order of  events is reversed: it appears that event B occurred before event A". Thus the observer on Proxima Centauri would think that if you traveled faster than the speed of light, you could travel from event B to event A. There is one problem though. How would you travel faster than the speed of light, if it is (right now) the fastest thing in the universe? Stephen Hawking explains that there is one possibility for overcoming the difficulty of traveling at such an immense speed, the idea of the wormhole. The concept of wormholes actually originated in a paper published by Einstein and another scientist in 1935, but they thought of it more in terms of a brief bridge connecting space and time. Modern theorists have surmised that time travel is possible if we could learn how to warp space and create a negative density in space (thing of it as bending space to create the shape of saddle) and then creating a shortcut, sort of like a tube, connecting two different areas of space and time (think of the outer ridges of the saddle). However, as Stephen Hawking points out, "One question is this: if it's possible to travel into the past why hasn't anyone com back from the future and told us how to do it?".

 

In all, for those interested in understanding the ultimate mystery of how the universe works, this is an enjoyable and captivating read. So much information is packed into this rather small but significant book. The main idea of the book was to try to find one complete theory of physics that explains everything in the universe.  Stephen Hawking shows us many of the theories that must be understood before it will be possible to arrive at a complete theory of physics. Every theory described was concise but full of information that was necessary to understand that particular theory. Personally, I feel like the ending of the book is a cliff-hanger though, as Stephen Hawking concedes that it might not be possible to find one complete theory of physics because there would need to be so many theories proposed in that one theory. He also suggests that if we discover the complete theory of physics, it may (relatively speaking) be a very long time before we discover a truly complete theory of physics, as it is necessary first to find a theory for every single aspect in the universe and then combine them into one theory. I highly recommend for those interested in physics, quantum physics, space, and time. It is well written, intelligent and highly informative. And maybe one day in the future, scientists will uncover the complete theory of physics that explains everything in the universe.  If so, Stephen Hawking will have helped to clear the path for this great discovery

The Physics of the Impossible

The Physics of the Impossible

Overview

       The Physics of the Impossible entails, not surprisingly, the physics of the impossible. The book is divided into three main parts respecting the three classes of impossibilities. The first level is a Class I impossibility, which means that the task has a good possibility to be accomplished in 100 years. An example of a Class I impossibility is creating a force field because we cannot do it today but in 100 years we may be able to. The second level is a Class II impossibility, which means it would take a very advanced civilization to accomplish the task. An example of a class II impossibility is time travel, because using quantum mechanics it is possible, just very unfeasible. The third level is a class III impossibility, which entails tasks that can not be accomplished with our current understanding of physics. An example of a Class III impossibility is a perpetual motion machine, because it violates the second law of thermodynamics, making it impossible using our current understanding of physics, and still extremely difficult if physics allowed it.

Book Cover

        I would rate the book an 8/10 because it had great content, but some of it felt like it was dragged out for longer than it needed to be. The book stated its claims and backed them up with evidence, moving logically from one topic to the another. I would highly recommend this book for people who are interested in physics, theoretical physics, quantum mechanics, and thermodynamics who have limited prior knowledge. I also love the formatting in the book, because it transitions from broader topics to more complex insights into the topic. All in all I highly recommend this book for everyone interested in science fiction and/or physics.

About the author

       Dr. Michio Kaku works as a professor of theoretical physics at the City College of New York. He was born on January 24th 1947, making him currently 68 years old. He has a Phd. in physics from Berkeley College and currently holds the Henry Semat Chair and Professorship in theoretical physics at the City College of New York. He has also written several physics textbooks and a few books about physics and the ways they work.

Dr. Michio Kaku