Contents
Foreword viii
List of illustrations and tables x
1 Journey to the centre of the universe 1
2 How big and small are big and small? 12
3 How we learn what things are made of, and what
we found 22
4 The heart of the matter 34
5 Accelerators: cosmic and manmade 46
6 Detectors: cameras and time machines 62
7 The forces of Nature 81
8 Exotic matter (and antimatter) 92
9 Where has matter come from? 106
10 Questions for the 21st century 116
Further reading 131
Glossary 133
Index 139
Foreword
We are made of atoms. With each breath you inhale a million billion
billion atoms of oxygen, which gives some idea of how small each one is.
All of them, together with the carbon atoms in your skin, and indeed
everything else on Earth, were cooked in a star some 5 billion years ago.
So you are made of stuff that is as old as the planet, one-third as old as
the universe, though this is the first time that those atoms have been
gathered together such that they think that they are you.
Particle physics is the subject that has shown how matter is built
and which is beginning to explain where it all came from. In huge
accelerators, often several miles in length, we can speed pieces of atoms,
particles such as electrons and protons, or even exotic pieces of
antimatter, and smash them into one another. In so doing we are
creating for a brief moment in a small region of space an intense
concentration of energy, which replicates the nature of the universe as it
was within a split second of the original Big Bang. Thus we are learning
about our origins.
Discovering the nature of the atom 100 years ago was relatively simple:
atoms are ubiquitous in matter all around, and teasing out their secrets
could be done with apparatus on a table top. Investigating how matter
emerged from Creation is another challenge entirely. There is no Big
Bang apparatus for purchase in the scientific catalogues. The basic
pieces that create the beams of particles, speed them to within an iota
of the speed of light, smash them together, and then record the results
for analysis all have to be made by teams of specialists. That we can
do so is the culmination of a century of discovery and technological
progress. It is a big and expensive endeavour but it is the only way that
we know to answer such profound questions. In the course of doing
so, unexpected tools and inventions have been made. Antimatter
and sophisticated particle detectors are now used in medical imaging;
data acquisition systems designed at CERN (the European
Organization for Nuclear Research) led to the invention of the World
Wide Web – these are but some of the spin-off from high-energy particle
physics.
The applications of the technology and discoveries made in high-energy
physics are legion, but it is not with this technological aim that the
subject is pursued. The drive is curiosity; the desire to know what we are
made of, where it came from, and why the laws of the universe are so
finely balanced that we have evolved.
In this Very Short Introduction I hope to give you a sense of what we
have found and some of the major questions that confront us at the start
of the 21st century.
Foreword viii
List of illustrations and tables x
1 Journey to the centre of the universe 1
2 How big and small are big and small? 12
3 How we learn what things are made of, and what
we found 22
4 The heart of the matter 34
5 Accelerators: cosmic and manmade 46
6 Detectors: cameras and time machines 62
7 The forces of Nature 81
8 Exotic matter (and antimatter) 92
9 Where has matter come from? 106
10 Questions for the 21st century 116
Further reading 131
Glossary 133
Index 139
Foreword
We are made of atoms. With each breath you inhale a million billion
billion atoms of oxygen, which gives some idea of how small each one is.
All of them, together with the carbon atoms in your skin, and indeed
everything else on Earth, were cooked in a star some 5 billion years ago.
So you are made of stuff that is as old as the planet, one-third as old as
the universe, though this is the first time that those atoms have been
gathered together such that they think that they are you.
Particle physics is the subject that has shown how matter is built
and which is beginning to explain where it all came from. In huge
accelerators, often several miles in length, we can speed pieces of atoms,
particles such as electrons and protons, or even exotic pieces of
antimatter, and smash them into one another. In so doing we are
creating for a brief moment in a small region of space an intense
concentration of energy, which replicates the nature of the universe as it
was within a split second of the original Big Bang. Thus we are learning
about our origins.
Discovering the nature of the atom 100 years ago was relatively simple:
atoms are ubiquitous in matter all around, and teasing out their secrets
could be done with apparatus on a table top. Investigating how matter
emerged from Creation is another challenge entirely. There is no Big
Bang apparatus for purchase in the scientific catalogues. The basic
pieces that create the beams of particles, speed them to within an iota
of the speed of light, smash them together, and then record the results
for analysis all have to be made by teams of specialists. That we can
do so is the culmination of a century of discovery and technological
progress. It is a big and expensive endeavour but it is the only way that
we know to answer such profound questions. In the course of doing
so, unexpected tools and inventions have been made. Antimatter
and sophisticated particle detectors are now used in medical imaging;
data acquisition systems designed at CERN (the European
Organization for Nuclear Research) led to the invention of the World
Wide Web – these are but some of the spin-off from high-energy particle
physics.
The applications of the technology and discoveries made in high-energy
physics are legion, but it is not with this technological aim that the
subject is pursued. The drive is curiosity; the desire to know what we are
made of, where it came from, and why the laws of the universe are so
finely balanced that we have evolved.
In this Very Short Introduction I hope to give you a sense of what we
have found and some of the major questions that confront us at the start
of the 21st century.
No comments:
Post a Comment