Paul Parsons - The Beginning and the End of Everything: From the Big Bang to the End of the Universe

THE
BEGINNING
AND
THE END
OF
EVERYTHING

First published in Great Britain in 2018

by Michael OMara Books Limited

9 Lion Yard

Tremadoc Road

London SW4 7NQ

Copyright Paul Parsons 2018

All rights reserved. You may not copy, store, distribute, transmit, reproduce or otherwise make available this publication (or any part of it) in any form, or by any means (electronic, digital, optical, mechanical, photocopying, recording or otherwise), without the prior written permission of the publisher. Any person who does any unauthorized act in relation to this publication may be liable to criminal prosecution and civil claims for damages.

A CIP catalogue record for this book is available from the British Library.

Image credit : comparison of CMB results / NASA / JPL-Caltech / ESA

ISBN: 978-1-78243-956-1 in hardback print format

ISBN: 978-1-78929-034-9 in trade paperback format

ISBN: 978-1-78243-966-0 in ebook format

ISBN: 978-1-78929-059-2 in audiobook

www.mombooks.com

Cover design: Ana Bjezancevic

Cover picture credit: www.shutterstock.com

Illustrations by Greg Stevenson

Dedicated to the memory of Professor Stephen W. Hawking

(19422018)

CONTENTS

Time = 0: Big Bang

The universe is brought into existence in a state of infinite density and temperature. Where just a split second earlier there was nothing, now mass, energy, space and time all spontaneously come into existence. No one knows what caused the Big Bang, or what existed before it.

Time = one 10-million-billion-billion-billion-billionth of a second: Planck era

The temperature is still 100,000 billion billion billion degrees. Space and time exist as hazy, indistinguishable entities, governed by the laws of quantum physics.

Time = one hundred-thousand-billion-billion-billionth of a second: inflation

The universe undergoes a rapid cosmic growth spurt, increasing in size exponentially fast, solving various cosmological problems and creating the seeds from which large-scale structures in the universe such as galaxies and clusters later grow.

Time = one millionth of a second: Quark era

The universe is a sea of quarks, the tiny particles that make up protons and neutrons.

Time = 1 second: Hadron era

As the temperature drops below around 1,000 billion degrees, quarks condense into protons and neutrons (known collectively as hadrons), the basic building blocks of atoms.

Time = 101,000 seconds: synthesis of light atomic nuclei

The temperature falls to a billion degrees, allowing protons and neutrons to stick together and begin forming the light chemical elements hydrogen, helium and a small quantity of lithium.

Time < 380,000 years: Radiation era

Although atomic nuclei exists at this time, the universe is still awash with fiercely hot radiation that rips apart any atoms attempting to form.

Time = 380,000 years: recombination

The temperature drops down to around 3,700 degrees C, allowing electrons to finally combine with protons to create the first atoms. The universe is now dominated by matter rather than radiation.

Time = 380,000180 million years: Dark Ages

The universe is dominated by matter, but none of it has formed stars or galaxies or anything else luminous.

Time = 180 million1 billion years: cosmic dawn

The first stars begin to shine an event known as the cosmic dawn, which brings the universes Dark Ages to an end.

Time = 1 billion10 billion years: structure formation

Galaxies, clusters and superclusters all begin to take shape from around 1 billion years after the Big Bang. Galaxies gather into clusters, and clusters gather into superclusters.

Time = 9.2 billion years: birth of the solar system

A cloud of hydrogen, helium and a few heavier elements circling around the Milky Way galaxy begin to collapse under its own gravity.The core of the cloud becomes a hot, young star, while around it a disc of material condenses and fragments into a mix of rocky, gaseous and icy bodies. This is the birth of our solar system.

Time = 13.8 billion years: present day

Today, the universe is in the stelliferous era the age of the stars. Astronomers expect the stelliferous era to last until the universe is 100,000 billion years old, after which the formation of new stars will cease. By this time the sun will be long dead.

Time > 100,000 billion years: far future

Beyond 100,000 billion years, the behaviour of the universe is a largely unknown quantity. Although there are a number of theoretical possibilities for how the universe might continue to evolve and how it will ultimately end its days.

O ne day, nearly 14 billion years ago, something remarkable happened.

Our universe was born.

The matter and energy making up everything that you can see around you in the world today this book, the air you breathe, the biological material in your body, the light from the sun and the distant stars; everything were all born out of that one single instant of creation. Today this material is spread across a truly vast universe. We dont know exactly how big that universe is, but just the bit we can see spans some 92 billion light-years (a light-year is the distance that light can travel in a year; a billion is 1,000 million). The light from the furthest object we can see (a very distant collection of stars called a galaxy) started its journey through space 13.4 billion years ago thats many billions of years before our own sun and solar system had even formed.

Looking up at the night sky on a clear evening you might wonder where it all came from, how all the matter in the universe organized itself into galaxies full of stars, where the vastness of space ends, and how long into the future our universe might continue to exist for.

These are questions that have vexed our greatest thinkers since the beginning of recorded history. And yet now we have many of the answers, a fact almost as remarkable as the answers themselves.

The Beginning and the End of Everything

For millennia, our beliefs about the universe were grounded in religion, and the notion of a creator and woe betide anyone who dared challenge this with more scientific alternatives. The earliest secular views of the universe werent perfect either. For example, the Ancient Greek philosophers placed the Earth at the centre of the universe, with the sun, the planets and the distant stars all wheeling around it. With the invention of the telescope in the seventeenth century, observations of the night sky the evidence against which theories of the universe can be tested started to accumulate. And with that, cosmology the study of the universe at large became a quantitative science.

Telescopic measurements of outer space began to whittle away at the permitted range of cosmological theories because any theory that didnt square with observations could immediately be discarded. In particular, astronomers discovered in the 1920s that space is expanding. This would reduce the number of mainstream viable theories to just two. One said the universe had a definite beginning in a superheated, superdense state; and the other said it had existed for ever. The debate raged between these two competing possibilities for decades, but was finally settled in the 1960s when observations demonstrated that the universe really was hotter and denser in the past.