WINNER 2009 CHOICE AWARD OUTSTANDING ACADEMIC TITLE! The typical introduction to physics leaves readers with the impression that physics is about 30 different, unconnected topics such as motion, forces, gravity, electricity, light, heat, energy, and atoms. More often than not, these readers are left to conclude that physics is mostly about boring, lifeless numbers.
Questioning the Universe: Concepts in Physics offers the nonscientist an alternative view: one that demonstrates how physics is perpetually evolving and shows how so many seemingly diverse concepts are intimately connected. In fact, one could argue that the most important ideas in modern physics are all about unification, and that these ideas are as fascinating as they are elegant.
Physicists today believe that Mother Nature is remarkably efficient and requires only a relatively small number of laws to keep her universe in working order. We may not yet know all of these laws; but at the center of physics is a faith that she is indeed understandable …and that someday, we will see her full beauty.
The purpose of this book is to tell readers the story of what we have learned about nature so far and how we have done it. Written to arouse curiosity, this compelling and readable work:
- Delves into the most basic laws regarding motion and energy, waves and particles
- Introduces modern theories, including relativity, quantum mechanics, and particle physics
- Describes the key role played by that elemental building block, the atom
- Discusses the evolution of the universe, including the formation of stars and the mystery of dark matter and dark energy
This book is not for those doing physics but is aimed at those who simply want to learn about physics, so it requires only the most minimal math. What it does require is a sense of curiosity, an appreciation of beauty, and the capacity for awe.
UNITS AND POWERS OF TEN
PHYSICS AND ITS METHODOLOGY
What Is Physics?
Methodology
The First Scientist
Why Do You Believe?
Back to the Questions
How Do We Answer the
Questions?
The Need to Be
Quantitative
Theories
Models
Aesthetic
Judgments
MOTION
Relating the Variables of Motion
Graphs of One-Dimensional Motion
Constant Speed
Constant Acceleration
Two-Dimensional Motion
FORCES
The Fundamental Forces
A Specific Force Law: Newtonian Gravity
Weight
How Does Force Affect Motion? Newton’s Second
Law
Newton, the Apple, and the Moon
Combining Two Laws
The Mass of the Earth
Newton’s First Law
What and Where Is the
Force?
Newton’s Third Law
How Does a Horse Pull a
Wagon?
How Can We Walk?
ELECTROMAGNETISM
The Electric Force Law
Unifying Electricity and Magnetism
Ampere’s Law
Faraday’s Law
The Lorentz Force
Back to Ampere’s
Law
Where Are the Moving
Charges?
THE
FIELD CONCEPT
What Is the Connection?
Action at a Distance
Is This a Legitimate
Explanation?
The Field Concept
How Does This Help
Explain Noncontact Forces?
Thinking Like a
Physicist
Is There a Way to Tell
the Difference?
Understanding the Time
Delay
The Speed and Identity
of the Kink
Back to Contact Forces
THE
CHARACTER OF NATURAL LAWS
Causality
The Prime Directive
Symmetry
Symmetry and the Laws of Nature
Space Translation
Symmetry
Time Translation
Symmetry
Time Reversal (Reflection)
Symmetry
Matter-Antimatter
Symmetry (Matter Reflection)
Space Reflection
Symmetry (Parity)
CONSERVATION
LAWS
Conservation of Momentum
Conservation of Energy
The Different Forms of
Energy
Conversion of Energy
A Specific Example: The
Roller Coaster
A Nonconservation Law: The Second Law of
Thermodynamics
THE
HISTORY OF THE ATOM
The Greek Model
Thomson’s “Plum Pudding” Model
The Rutherford Experiment
The Planetary Model
What Do We Do Now?
The Atom Today
The Electron Volt: A Useful Energy Unit
THE
NUCLEUS
Nuclear Properties
Why Neutrons?
Nuclear Decays
Alpha Decay
Beta Decay
Gamma Decay
Half-Life and Carbon Dating
The Full Beta Decay Story
The Prediction
The Experimental
Results
What Do We Do Now?
Look Closely at the
Theory
Look Closely at the
Experimental Results
A Possible Explanation
THE
NATURE OF LIGHT
Properties of Particles
Properties of Waves
Wave Vocabulary
Is Light Made Up of Waves or Particles?
Back to Diffraction
Why the Sky Is Blue
THE
THEORY OF RELATIVITY
Frames of Reference and Relative Speeds
Galilean Relativity
Maxwell and the Ether
The Speed of Waves
The Ether
The Michelson Morley Experiment
An Analogy: Boats in a
River
The Real Experiment
The Lorentz Contraction
Another Crazy Idea
Assumptions We Take for Granted
The Postulates of Special Relativity
Some Interesting Facts
about Einstein and the
Birth of Relativity
Consequences of the Postulates of
Relativity
The Relativity of
Simultaneity
Time Dilation
The Light Clock
Useful Definitions
Length Contraction
Length and Lorentz Contraction
E = mc2 and All That
Back to Addition of Speeds
The Car in the Garage Paradox
The Twin Paradox and Space Travel
Relativity and You
QUANTUM
MECHANICS
Max Planck and the Beginnings of Quantum
Theory
The Photoelectric Effect
The Bohr Atom
de Broglie Waves
Time to Stop and Catch Our Breath
The Heisenberg Uncertainty Principle
The Schrodinger Equation: An Equation for the
Waves
Does God Play Dice?
THE
STANDARD MODEL OF ELEMENTARY PARTICLE PHYSICS
The Basic Ideas of the Standard Model
The Unification of Forces
Bosons: The Particles Associated with Forces
Electroweak Unification
The Unification of Matter
Two Classes of Matter
Particles
Similarities
Differences
More about Quarks
More about Leptons
A Mystery
Particle Flowchart
COSMOLOGY
The Expansion of the Universe
Measuring Speeds Using
the Doppler Effect
Measuring
Distances
Nearby Stars
More Distant Stars:
Standard Candles
Light from the Big Bang: CMB Radiation
The Evolution of the Universe
The Planck Time
The GUT Time
The Disappearance of
Antimatter
Two Sticky Problems and
a Solution
The Solution: Inflation
The Electroweak Time
The Formation of
Particles
The Formation of
Nuclei
The Formation of Atoms
The Formation of Stars
and Galaxies
Dark Matter
Dark Energy
EPILOGUE
SUGGESTED
FURTHER READINGS
INDEX
Each chapter ends with a Guide to Key Ideas and
Biography
Ahren Sadoff
"I have been teaching introductory physics for non-science majors for a long time and have never been satisfied with the books on the market. Most of these texts are just watered-down versions of the general physics texts for science students. When I read through [these] three books, I really do get a sense that the authors have attempted to create book[s] that [are] somehow different from the normal algebra problem-based texts. I will be using Questioning the Universe: Concepts in Physics this fall for the science portion of a Science Fiction Learning Community. In the spring, I will be teaching a physics/art history hybrid course and will be using either Superstrings and Other Things: A Guide to Physics, Second Edition or From Atoms to Galaxies: A Conceptual Physics Approach to Scientific Awareness. … both are great books. … I really feel that for conceptual physics courses, CRC Press currently has the three strongest titles. I anticipate a fun teaching experience while using these texts and hope to use them again in the future."
—Steve Zides, Wofford College, Spartanburg, South Carolina, USAWINNER OF 2009 CHOICE AWARD FOR BEST ACADEMIC TITLE!
"This introductory physics book is quite different (in a positive way) from all of the other similar works this reviewer has seen. In just over 200 pages and 15 chapters, Sadoff delves into just about every area of physics, ranging from basic Newtonian mechanics to fields, light, nuclear physics, relativity, and quantum mechanics … he successfully ties the various subjects together."
—J.R. Kraus, University of Denver, CHOICE, August 2009, Vol. 46, No. 1
