Chapter 1 - Origin of the Universe

Abstract

This chapter discusses origin of the universe. In Newton's time, the universe was pictured as an infinite sea of stars in fixed positions. The only movements that astronomers were aware of were those of the planets about the sun and satellites about the planets. Newton argued that the stars were scattered across an infinite expanse of space in more or less fixed positions. In proposing this model for the universe, Newton's attention was focused on the balance of gravitational forces. Einstein's theory of relativity changed our thinking about space and time, but even Einstein did not reject the concept of an infinite static universe despite the inconsistency of this model with his own theory. Hubble's model for the universe was the outcome of research that permitted him to estimate the movement of the stars relative to the Earth. The main way in which such studies are made is by analyzing the light they emit, the distance of different galaxies, and the speed with which they are moving relative to one another. It has been estimated that all matter and energy originated from a single location in the Big Bang about 20 billion years ago. The universe may keep expanding or the expansion may give way to arrest or even contraction. Current indications from measured recessional velocities of very distant supernovas favor the notion of indefinite expansion.