Sadoff Questioning the Universe

Concepts in Physics
1. Auflage 2011
ISBN: 978-1-4200-8259-3
Verlag: Taylor & Francis
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 224 Seiten

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.

Zielgruppe

non-science undergraduate majors

Autoren/Hrsg.

Sadoff, Ahren

Fachgebiete

• Naturwissenschaften Physik Physik Allgemein

Inhaltsverzeichnis

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

Questions/Problems