Alternative histories • a formulation of quantum theory in which the probability of any observation is constructed from all the possible histories that could have led to that observation.
Anthropic principle • the idea that we can draw conclusions about the apparent laws of physics based on the fact that we exist.
Antimatter • each particle of matter has a corresponding anti-particle. If they meet, they annihilate each other, leaving pure energy.
Apparent laws • the laws of nature that we observe in our universe—the laws of the four forces, and the parameters such as mass and charge that characterize the elementary particles—in contrast to the more fundamental laws of M-theory that allow for different universes with different laws.
Asymptotic freedom • a property of the strong force that causes it to become weaker at short distances. Hence, although quarks are bound in nuclei by the strong force, they can move within nuclei almost as if they felt no force at all.
Atom • the basic unit of ordinary matter, consisting of a nucleus with protons and neutrons, surrounded by orbiting electrons.
Baryon • a type of elementary particle, such as the proton or neutron, that is made of three quarks.
Big bang • the dense, hot beginning of the universe. The big bang theory postulates that about 13.7 billion years ago the part of the universe we can see today was only a few millimeters across. Today the universe is vastly larger and cooler, but we can observe the remnants of that early period in the cosmic microwave background radiation that permeates all space.
Black hole • a region of space-time that, due to its immense gravitational force, is cut off from the rest of the universe.
Boson • an elementary particle that carries force.
Bottom-up approach • in cosmology, an idea that rests on the assumption that there’s a single history of the universe, with a well-defined starting point, and that the state of the universe today is an evolution from that beginning.
Classical physics • any theory of physics in which the universe is assumed to have a single, well-defined history.
Cosmological constant • a parameter in Einstein’s equations that gives space-time an inherent tendency to expand.
Electromagnetic force • the second strongest of the four forces of nature. It acts between particles with electric charges.
Electron • an elementary particle of matter that has a negative charge and is responsible for the chemical properties of elements.
Fermion • a matter-type elementary particle.
Galaxy • a large system of stars, interstellar matter, and dark matter that is held together by gravity.
Gravity • the weakest of the four forces of nature. It is the means by which objects that have mass attract each other.
Heisenberg uncertainty principle • a law of quantum theory stating that certain pairs of physical properties cannot be known simultaneously to arbitrary precision.
Meson • a type of elementary particle that is made of a quark and an anti-quark.
M-theory • a fundamental theory of physics that is a candidate for the theory of everything.
Multiverse • a set of universes.
Neutrino • an extremely light elementary particle that is affected only by the weak nuclear force and gravity.
Neutron • a type of electrically neutral baryon that with the proton forms the nucleus of an atom.
No-boundary condition • the requirement that the histories of the universe are closed surfaces without a boundary.
Phase • a position in the cycle of a wave.
Photon • a boson that carries the electromagnetic force. A quantum particle of light.
Probability amplitude • in a quantum theory, a complex number whose absolute value squared gives a probability.
Proton • a type of positively charged baryon that with the neutron forms the nucleus of an atom.
Quantum theory • a theory in which objects do not have single definite histories.
Quark • an elementary particle with a fractional electric charge that feels the strong force. Protons and neutrons are each composed of three quarks.
Renormalization • a mathematical technique designed to make sense of infinities that arise in quantum theories.
Singularity • a point in space-time at which a physical quantity becomes infinite.
Space-time • a mathematical space whose points must be specified by both space and time coordinates.
String theory • a theory of physics in which particles are described as patterns of vibration that have length but no height or width—like infinitely thin pieces of string.
Strong nuclear force • the strongest of the four forces of nature. This force holds the protons and neutrons inside the nucleus of an atom. It also holds together the protons and neutrons themselves, which is necessary because they are made of still tinier particles, quarks.
Supergravity • a theory of gravity that has a kind of symmetry called supersymmetry.
Supersymmetry • a subtle kind of symmetry that cannot be associated with a transformation of ordinary space. One of the important implications of supersymmetry is that force particles and matter particles, and hence force and matter, are really just two facets of the same thing.
Top-down approach • the approach to cosmology in which one traces the histories of the universe from the “top down,” that is, backward from the present time.
Weak nuclear force • one of the four forces of nature. The weak force is responsible for radioactivity and plays a vital role in the formation of the elements in stars and the early universe.
THE UNIVERSE HAS A DESIGN, and so does a book. But unlike the universe, a book does not appear spontaneously from nothing. A book requires a creator, and that role does not fall solely on the shoulders of its authors. So first and foremost we’d like to acknowledge and thank our editors, Beth Rashbaum and Ann Harris, for their near-infinite patience. They were our students when we required students, our teachers when we required teachers, and our prodders when we required prodding. They stuck with the manuscript, and did it in good cheer, whether the discussion centered around the placement of a comma or the impossibility of embedding a negative curvature surface axisymmetrically in flat space. We’d also like to thank Mark Hillery, who kindly read much of the manuscript and provided valuable input; Carole Lowenstein, who did so much to help with the interior design; David Stevenson, who guided the cover to completion; and Loren Noveck, whose attention to detail has saved us from some typos we would not like to have seen committed to print. To Peter Bollinger: much gratitude for bringing art to science in your illustrations, and for your diligence in ensuring the accuracy of every detail. And to Sidney Harris: Thank you for your wonderful cartoons, and your great sensitivity to the issues facing scientists. In another universe, you could have been a physicist. We are also grateful to our agents, Al Zuckerman and Susan Ginsburg, for their support and encouragement. If there are two messages they consistently provided, they were “It’s time to finish the book already,” and “Don’t worry about when you’ll finish, you’ll get there eventually.” They were wise enough to know when to say which. And finally, our thanks to Stephen’s personal assistant, Judith Croasdell; his computer aide, Sam Blackburn; and Joan Godwin. They provided not just moral support, but practical and technical support without which we could not have written this book. Moreover, they always knew where to find the best pubs.
Air, discovery of
Almagest (Ptolemy)
Alternative histories. See also Quantum physics/quantum theory
Feynman diagrams and
Feynman’s sum over histories and
the past and
quantum vs. Newtonian worlds and
universe and
Anaximander
Anthropic principle
strong anthropic principle
weak anthropic principle
Antimatter
Anti-quarks (pi mesons)
Anti
-realists
Apparent laws of nature
Aquinas, Thomas
Archimedes
Aristarchus
Aristotle
creation as deliberate design
four-element theory
on no exceptions to natural laws
rate of falling objects theory
reason for principles of nature
use of reason instead of observation
Asymptotic freedom
Atomism
Atoms
hydrogen, Lamb shift and
quarks, protons, and neutrons
strong nuclear force and
Augustine of Hippo, St.
Babylonians
Baryon
Berkeley, George
Beryllium
Big bang theory
CMBR and
evidence of
irregular universe and inflation
as spontaneous quantum event
when it happened
Black hole
Boshongo people
Boson
Brain
model building of
Buckyballs
buckyball soccer
particle paths
Buoyancy, law of
Caenorhabditis elegans
Carbon
as basis for life
creation of, in primordial universe
triple alpha process and
in universe
Carroll, John W.
Cathode rays
CERN, Geneva
Chemistry
Chinese philosophy and mythology
God as Creator
tale of the ten suns
Christianity
creation as deliberate design
John XXI’s list of heresies, science and
miracles
natural laws as obedient to God
notion of free will and purpose
Ptolemaic model adopted by Roman Catholic Church
rejection of indifferent natural laws
Roman Catholic Church acknowledges wrong to Galileo
Clepsydra
Conway, John
Copernicus
Corpuscle theory
Cosmic microwave background radiation (CMBR)
evidence of inflation and
Cosmological constant
Cosmology. See also Universe
“bottom up” approach
grand design and
laws of nature as “fine-tuned”
number of dimensions in the universe
predictions in
“top down” approach
Crater Lake, Oregon
Creation. See also Life; Universe
account in Genesis
big bang theory
empirical evidence of
God as Creator
as godless
of life
M-theory and
myths
origin of the universe
spontaneous quantum creation of the universe
Curvature/curved spaces
geodesics
great circle
Darwin, Charles
Davisson, Clinton
Davy, Sir Humphrey
Delayed-choice experiments
Democritus
De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres [Copernicus])
Descartes, René
Dicke, Robert
Double-slit experiment
buckyball soccer
delayed-choice experiments
Feynman’s insight
particle paths
two-slit soccer
“which-path” information
Dualities
Earth
as center of the universe
cessation of rotation
Copernican model and
creation
curvature of, and geodesics
eclipse and
ether (luminiferous ether) and
gravity and
as hospitable to life
laws of nature and
Mercator projection, world map
orbit
planetary system of
Ptolemaic model and
seasonal weather patterns
speed of
Eccentricity of elliptical orbits
Eclipse (lunar or solar)
prediction of
Economics
Eddington, Arthur
Effective theory
Egyptian creation myth
Einstein, Albert
cosmological constant
on creation of the universe
expanding universe and
general relativity
photoelectric effect
special relativity
on time
on unified theory
on the universe
Einstein’s theory of relativity
general relativity
GPS satellite navigation systems and general relativity
space-time and general relativity
special relativity
Electromagnetic force
bosons and
electroweak force and
light and
Maxwell’s equations
QED and
speed of electromagnetic waves
Electrons
double-slit experiment and
Feynman diagrams and
particle paths
Electroweak force
three new particles discovered
Elegance, of models
Empedocles
Energy
constant zero
of empty space
of universe
Epicurus
Ether (luminiferous ether)
Euclid
Evolution
Faraday, Michael
Fermion
Feynman, Richard (Dick)
Feynman diagrams
Feynman paths
QED and
sum over histories
van owned by
FitzGerald, George Francis
Force fields
bosons
fermions
Fowler, William
Free will
Friedmann, Alexander
Fuller, Buckminster
Galaxies
alternative histories and
cosmological constant and
expanding universe and
heavy elements and formation of
inhomogeneities in universe and
light from distant
number of and stars in
planetary systems of
quantum fluctuations and formation of
Galileo
rate of falling objects theory
Game of Life
blinkers
evolution of a still life
glider guns
gliders
still-life blocks
Geodesics
Germer, Lester
God (or gods)
as causal in nature
creation and
as dice-thrower
first-cause argument
Joshua praying for the sun and moon to halt
natural laws, human statues and
natural laws and
Newton’s belief in God’s intervention
universe as God’s dollhouse
what happened before the world existed?
Grand design
laws of nature as “fine-tuned” and
no-boundary condition and
Grand unified theories (GUTS)
Gravitational waves
Gravity
cosmological constant
cosmological constant and
creation of stars, galaxies, planets
effective theory and
Einstein’s general relativity and
galaxies and
mathematical
formulation of theory
M-theory and
Newton’s law of
orbits and three dimensions
quantum theory and
as shaper of space-time
standard model not applicable
supergravity theory
warpage of time and space by
as weak force
Great circle
Greece, ancient
distinction between human and natural laws lacking
Ionian science
laws of nature and
questions of creation and
scientific method lacking
Stoics
“Grimnismal” (The Elder Edda)
Harris, Sidney, cartoons by
Heisenberg, Werner
Heisenberg uncertainty principle
empty space, impossibility of, and
Planck’s constant
Helium
big bang theory and
creation of beryllium, carbon, and
in primordial universe
Heraclitus
Hitchhiker’s Guide to the Galaxy
Holographic principle
Hoyle, Fred
Hubble, Edwin
Humans. See also Life
creation of, Biblical
definition of living beings
existence relative to cosmic history
free will and
natural laws and
origins of homo sapiens
psychology as study of will and behavior
robot vs.
self-awareness
soul of
written language and cultivation begun
Hume, David
Hydrogen
fusion, in stars
isotopes
Lamb shift and
in primordial universe
Inertia, law of
Inflation theory
irregular universe and
“Initial conditions”
Intelligent design
Interference
constructive
destructive
double-slit experiment
Newton’s rings and
puddle interference
“which-path” information and
Young’s experiment and
Ionian science
Johnson, Samuel
John XXI, Pope
Kelvin, William Thomson, Lord