Six Easy Pieces: Essentials of Physics Explained by Its Most Brilliant Teacher

177 Pages·2011·1.71 MB·English

by  Richard P. Feynman

SCIENCE
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I t was Richard Feynman’s outrageous and scintillating method of teaching that earned i “The most original mind of his generation.” —Freeman Dyson
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him legendary status among students and professors of physics. From 1961 to 1963,
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Feynman delivered a series of lectures at the California Institute of Technology that
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revolutionized the teaching of physics around the world. Six Easy Pieces, taken from these R
RichaRd p. Feynman
famous Lectures on Physics, represent the most accessible material from the series. d 6

In these classic lessons, Feynman introduces the general reader to the following
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topics: atoms, basic physics, energy, gravitation, quantum mechanics, and the relationship

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of physics to other topics. With his dazzling and inimitable wit, Feynman presents each
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discussion with a minimum of jargon. Filled with wonderful examples and clever illustrations,
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Six Easy Pieces is the ideal introduction to the fundamentals of physics by one of the most n
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admired and accessible physicists of modern times. m
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“The essence of physics and Feynman. No jargon, just ideas, excitement, and the
straight dope. And real answers, like ‘we don’t know.’ ” —sTephen WolFram
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i
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The late RichaRd P. Feynman (1918–1988) was Richard Chace Tolman Professor of

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Theoretical Physics at the California Institute of Technology. He was awarded the 1965
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Nobel Prize for his work on the development of quantum field theory. He was also one of
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the most famous and beloved figures of the twentieth century, both in physics and in the y
BASIC
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SIX EASY PIECES
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Also by Richard P. Feynman
The Character of Physical Law
Elementary Particles and the Laws of Physics:
The 1986 Dirac Memorial Lectures (with Steven Weinberg)
Feynman Lectures on Computation
(edited by Anthony J. G. Hey and Robin Allen)
Feynman Lectures on Gravitation (with Fernando B. Morinigo and
William G. Wagner; edited by Brian Hatfield)
The Feynman Lectures on Physics
(with Robert B. Leighton and Matthew Sands)
The Meaning of It All: Thoughts of a Citizen-Scientist
Photon-Hadron Interactions
Perfectly Reasonable Deviations from the Beaten Track:
The Letters of Richard P. Feynman
The Pleasure of Finding Things Out:
The Best Short Works of Richard P. Feynman
QED: The Strange Theory of Light and Matter
Quantum Mechanics and Path Integrals (with A. R. Hibbs)
Six Not-So-Easy Pieces:
Einstein’s Relativity, Symmetry, and Space Time
Statistical Mechanics: A Set of Lectures
Surely You’re Joking, Mr. Feynman!
Adventures of a Curious Character (with Ralph Leighton)
The Theory of Fundamental Processes
What Do You Care What Other People Think?
Further Adventures of a Curious Character
(with Ralph Leighton)
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S I X E A S Y P I E C E S
Essentials of Physics Explained
by Its Most Brilliant Teacher
R I C H A R D P. F E Y N M A N
with
Robert B. Leighton
and
Matthew Sands
Introduction by
Paul Davies
A Member of the Perseus Books Group
New York
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Copyright © 1963, 1989, 1995, 2011 by the California Institute of Technology
Published by Basic Books,
A Member of the Perseus Books Group
All text and cover photographs are courtesy of the Archives, California Institute
of Technology.
All rights reserved. Printed in the United States of America. No part of this book
may be reproduced in any manner whatsoever without written permission except
in the case of brief quotations embodied in critical articles and reviews. For
information, address Basic Books, 387 Park Avenue South, New York, NY
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Books published by Basic Books are available at special discounts for bulk
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Department at the Perseus Books Group, 2300 Chestnut Street, Suite 200,
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[email protected].
Library of Congress Control Number: 2010941330
ISBN: 978-0-465-02527-5
E-book ISBN: 978-0-465-02529-9
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CONTENTS
Publisher’s Note vii
Introduction by Paul Davies ix
Special Preface xix
Feynman’s Preface xxv
ONE:Atoms in Motion 1
Introduction 1
Matter is made of atoms 4
Atomic processes 10
Chemical reactions 15
TWO:Basic Physics 23
Introduction 23
Physics before 1920 27
Quantum physics 33
Nuclei and particles 38
THREE:The Relation of Physics to Other Sciences 47
Introduction 47
Chemistry 48
Biology 49
Astronomy 59
Geology 61
Psychology 63
How did it get that way? 64
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Contents
FOUR:Conservation of Energy 69
What is energy? 69
Gravitational potential energy 72
Kinetic energy 80
Other forms of energy 81
FIVE:The Theory of Gravitation 89
Planetary motions 89
Kepler’s laws 90
Development of dynamics 92
Newton’s law of gravitation 94
Universal gravitation 98
Cavendish’s experiment 104
What is gravity? 107
Gravity and relativity 112
SIX:Quantum Behavior 115
Atomic mechanics 115
An experiment with bullets 117
An experiment with waves 120
An experiment with electrons 122
The interference of electron waves 124
Watching the electrons 127
First principles of quantum mechanics 133
The uncertainty principle 136
Index 139
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PUBLISHER’S NOTE
Six Easy Pieces grew out of the need to bring to as wide an audience
as possible a substantial yet nontechnical physics primer based on
the science of Richard Feynman. We have chosen the six easiest
chapters from Feynman’s celebrated and landmark text, The Feyn-
man Lectures on Physics (originally published in 1963), which re-
mains his most famous publication. General readers are fortunate
that Feynman chose to present certain key topics in largely quali-
tative terms without formal mathematics, and these are brought to-
gether for Six Easy Pieces.
We would like to thank Paul Davies for his insightful introduc-
tion to this newly formed collection. Following his introduction
we have chosen to reproduce two prefaces from The Feynman Lec-
tures on Physics, one by Feynman himself and one by two of his col-
leagues, because they provide context for the pieces that follow and
insight into both Richard Feynman and his science.
Finally, we would like to thank the California Institute of Tech-
nology’s Physics Department and Institute Archives, in particular
Dr. Judith Goodstein, and Dr. Brian Hatfield, for his outstanding
advice and recommendations throughout the development of this
project.
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INTRODUCTION
There is a popular misconception that science is an impersonal,
dispassionate, and thoroughly objective enterprise. Whereas most
other human activities are dominated by fashions, fads, and per-
sonalities, science is supposed to be constrained by agreed rules of
procedure and rigorous tests. It is the results that count, not the
people who produce them.
This is, of course, manifest nonsense. Science is a people-driven
activity like all human endeavor, and just as subject to fashion and
whim. In this case fashion is set not so much by choice of subject
matter, but by the way scientists think about the world. Each age
adopts its particular approach to scientific problems, usually fol-
lowing the trail blazed by certain dominant figures who both set
the agenda and define the best methods to tackle it. Occasionally
scientists attain sufficient stature that they become noticed by the
general public, and when endowed with outstanding flair a scientist
may become an icon for the entire scientific community. In earlier
centuries Isaac Newton was an icon. Newton personified the gen-
tleman scientist—well connected, devoutly religious, unhurried,
and methodical in his work. His style of doing science set the stan-
dard for two hundred years. In the first half of the twentieth cen-
tury Albert Einstein replaced Newton as the popular scientist icon.
Eccentric, dishevelled, Germanic, absent-minded, utterly absorbed
in his work, and an archetypal abstract thinker, Einstein changed
the way that physics is done by questioning the very concepts that
define the subject.
Richard Feynman has become an icon for late twentieth-century
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