Time and Space (3A18)

Good morning principal, teachers and my fellow schoolmates. I am Chong Pak Yeung in 3A. The book I want to share with you today is {Time and Space} written by Mary and John Gribbin. This book covers time, space, and measurement, the structure of the universe, the theory of relativity, black holes, quantum mechanics, and string theory. The chapters impressed me most are the structure of universe and how time and space are measured. In the past, people didn’t know much about the Earth; Greek thinkers described the earth as a flat disc circled by a river or a round sphere. People at that time had inadequate knowledge about the Universe too. Ancient people relied on agriculture and it is important to measure the passage of the seasons. To measure it, they put a stick upright in the ground and observed the movement of the shadow of the stick every day. As time passes, scientists invented many useful tools such as hourglasses, pendulum clock in order to have an accurate calculation of time.

This book also explores the future of time and space. It talks about the general theory of relativity. Einstein proved that time travel is permitted. Black holes have two ‘ends’. The openings are possibly in different times so that we can use it for time travel. However, scientist found it is difficult to build a working time machine as there are still many problems to be resolved. Scientists are working hard to turn time travel into reality. I hope we can have a time travel soon and explore the Earth from the past to the future by the time machine. 
 
This book is a very good introduction to Physics. It is very informative and it explains things perfectly for young students. I learned a lot from the book. For examples, if you walk around the circumference of the earth at a steady pace of 37 miles per hour, you would finish your trip in just under a month. But taking an areophane at 500 miles per hour, it would take 21 years to travel from the Earth to the Sun. Another interesting fact is, scientific evidence shows that there really was a definitely beginning to the universe, which would mean that there is an ‘edge’ of time. 
Also, there are many wonderful photos and pictures in this book which enable us to understand complex terms and concepts easily. I recommend this book to all of you because it will give you a wonderful experience in learning Physics. 
Thank you.