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

218 Pages·2018·3.01 MB·English

by  Paul Parsons

THE
BEGINNING
AND
THE END
OF
EVERYTHING

Dedicated to the memory of Professor Stephen W. Hawking
(1942–2018)
CONTENTS
Timeline
Introduction
1: Our Place in the Universe
2: The Theory Within the Theory
3: The Expanding Cosmos
4: Two Smoking Barrels
5: Most of Our Universe is Missing
6: A Quantum Interlude
7: Into Darkness
8: The Even Bigger Bang
9: The Birth of Galaxies
10: From Out of Nowhere
11: Worlds in Parallel
12: Crunch Time
13: The Long Dark Eternity
14: Into the Unknown
Acknowledgements
Index
TIMELINE
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 = 10–1,000 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 = 380,000–180 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 million–1 billion years: cosmic dawn
The first stars begin to shine – an event known as the cosmic dawn, which brings
the universe’s Dark Ages to an end.
Time = 1 billion–10 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.