There are as I said multiple topics he discusses such as how the universe works. In chapter 1 he talks about Aristotle’s theory on how he thought the earth was a sphere and not just a flat surface. “If the earth had been a flat disk, the shadow would have been elongated and elliptical, unless the eclipse always occurred at a time when the sun was directly under the center of the disk.” (2).
Hawking also talked about the controversy between Galileo Galilee and Aristotle on the argument that weight did not affect gravity’s pull on the object. As we know today Galilee had proven Aristotle’s theory to be fallible because two objects of different masses do fall at the same rate. “Galileo’s measurements indicated that each body increased speed at the same rate, no matter its weight.
This book is consisted of a lot of theoretical physics, which pretty much means is a lot of theories about physics whether it is right or wrong. Stephen Hawking gives a miniscule overview about how the current information was developed. From the universe, elementary particles, black holes, and the beginnings of the universe also what follows?
He also covered Ptolemy’s contribution, created a model showing the bodies of the solar system. But there was a man who did not agree with Ptolemy and his name was Nicholas Copernicus, he believed in a heliocentric system which pretty much means the sun is at the center of everything. Galileo Galilee and Johannes Kepler shortly have noticed other moons of many other planets in the system that proved Copernicus’ theory to be correct.