A Brief History of Time

A Brief History of Time is a book written by mathematician and scientist, Stephen Hawking in 1988. The non-fiction novel discusses many topics such as physics and how everything works in the world. Hawking discusses the theories in physics such as gravity, how light moves the universe and much more. Hawking also speaks about cosmology and how people see the universe and how it exists.

In chapter one, Hawking speaks about the history of physics and philosophers such as Aristotle and Ptolemy and their ideas. Aristotle believed that the Earth was round and the sun and stars revolved around the Earth. Ptolemy made a planetary model to describe Aristotle’s ideas. With the technology we have today, we know that the Earth revolves around the sun and not the other way around. In 1609 Ptolemy and Aristotle’s ideas were disproved of by Nicholas Copernicus and Galileo Galilei and Johannes Kepler were there to support him. Isaac Newton wrote a book to help prove Copernicus’s idea.

In chapter two, space and time are the main topic. Hawking describes how gravity works between the planets and the sun. In 1676, Ole Christensen Roemer discovered the speed of light. Scientists created an idea called ether which tired to explain light’s speed. However, Albert Einstein said ether was not needed but rather the idea of absolute time. Light is also mentioned and light cones can describe any event. The top of the cone tells where the light will travel, the center tells the event and the bottom tells where the light has been in the past. The next topic is the theory of relativity.

In chapter three, Hawking speaks about expanding the universe. He believes that the universe is becoming larger over time. He uses the Doppler shift to prove his idea. The Doppler shift happens when something moves toward or away from another object. There are two types of things that happen in Doppler shift - red shifting and blue shifting. Red shifting happens when something is moving away from us. Blue shifting happens when something is moving toward us, the opposite process of red-shift.

In Chapter four, the uncertainty principle is mentioned where the speed and the position of a particle cannot be found at the same time. The behaviors of light acts like particles even though it’s made of rays.

Chapter five talks about elementary particles and that everything is made of matter. Quarks are what make up matter and they also have color. All quarks have what is called a spin which is what shows how a particle looks from different angles.

Chapter six and seven talks black holes. Black holes are starts that have broken down into a small point called singularity. Black holes have a very strong gravitational pull because it sucks things into its center. Black holes can only become bigger and not smaller and chapter eight talks about how the universe began and possibilities on how it may end.

This book relates to many topics in science. It relates to physics, the very important scientists who provided the steppingstone for today’s technologies like Einstein and Galileo and how the universe began. This book sets the foundation for everything about science. The book talks about how the universe began, which is the beginning of everything.

Stephen Hawking’s has affected millions of people with this book. After selling over four million copies and have this book as a New York Times best seller for four years, it’s bound to have impacted many people’s lives. Hawking’s takes the ideas of the brilliant scientists and he adds his opinion to the mix like how the universe will end. He also uses language that everyone can understand. His words are simple yet effective.

To this day, this book has left a mark in the science community; a mark that leaves scientists and the public with no further questions because all have been answered.