It is standard practice for experimenters to report how many quarks and gluons are produced in the reactions they study, how they are distributed in energy and angle, and so forth. What they’ve actually observed is the corresponding jets, but the identification, after thousands of successful applications, has become routine. Quarks and gluons entered the world as weird, suspect theoretical phantoms—confined particles that, according to theory, would never be observed in isolation. Tamed by beautiful ideas, they’ve become tangible realities— not mere particles, but jets.
GEOMETRY OF SPACE AND DENSITY OF MATTER
General relativity predicts a striking relationship between the average curvature of space, the average density of matter within it, and the rate of expansion of the universe. If the total density of matter is equal to a certain critical density, then space will be flat; if the density is larger, it will be positively curved, like a sphere; if the density is smaller, it will be negatively curved, like a saddle.
At present, the critical density is about 10−29 grams per cubic centimeter. This is equivalent to the mass of about six hydrogen atoms per cubic meter. Though this critical density is far below the density of the best “ultra-high vacuum” people have achieved in laboratories on Earth, it seems that it is close to the average density of the universe as a whole.
Astronomers can measure the shape of space geometrically, using sophisticated versions of the procedures we indicated in chapter 1. They can also measure the density, by adding up contributions from ordinary matter, dark matter, and dark energy. They find that space is very nearly flat, and that the density is very nearly the critical density. This is consistent with the prediction of general relativity. That consistency encourages us to think that the dark matter and dark energy mysteries can be understood within the framework of general relativity. Certainly, they do not require its modification.
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Index
The page numbers in this index refer to the printed version of this book. The link provided will take you to the beginning of that print page. You may need to scroll forward from that location to find the corresponding reference on your e-reader.
abundance, xiv–xv, 13–15
See also energy abundance; material abundance; spatial abundance; time
acceleration, 16, 115, 116
excess, explaining, 193–96
Adams, John Couch, 194
afterglows
of the big bang, 152, 154–55, 157–59, 163, 200, 202
of neutron star mergers, 182
See also dark matter
AHUMEN (Annual Human Energy), 127
Allegory of the Cave, 168–69
Almagest (Ptolemy), 6
AlphaZero, 204
analysis and synthesis method, 8
angular momentum, 74, 75–76
animals, perception in, 169–70, 171
Annual Human Energy (AHUMEN), 127
antineutrinos, 48, 118, 119, 151
antiquarks, 114, 151
anyons, 89–90
Arovas, Dan, 89
art, visual, 217
artificial intelligence, 54, 58, 59, 70–71, 204, 220–22
See also information flows and processing
astronomy and cosmology, 128
abundance and uniformity of matter in the cosmos, 21–22, 38, 149–51, 156, 161–62
astronomical observation, 5–6, 21, 22
astronomical timekeeping, 45
cosmic horizon, 28–31
Ptolemy’s synthesis, 6–7
Ramsey on astronomy, 42
and spectroscopy, 109
surveying the cosmos, 21–28
See also big bang theory; galaxies; planets; stars; universe; entries beginning with “cosmic”
asymptotic freedom, 112, 123–24, 149, 203, 238, 239
ATLAS detector, 176
atomic clocks, 17, 18–19, 55–56, 68–69
atomic nuclei
components and properties of, 62, 79, 84, 85, 105, 109–10
original formation of, 155, 163
and weak force processes, 119
See also QCD
atomic spectra, 106–9
atoms
atomic models and complementarity, 214–15
as building blocks of complexity, 130–32
structure of, 35–37, 62, 78–79, 83, 103, 105–6
viewed as basic building blocks, 61–62, 72, 96
See also atomic nuclei
Augustine, Saint, 44, 159, 219
axions, 122, 159, 166, 201–2
babies. See infant development
Barish, Barry, 180
bats, 170
bees, 171
big bang theory, 29, 146, 148–55
afterglows of the big bang, 152, 154–55, 157–59, 163, 200, 202
assumptions and principles of, 148–52, 163
and dark matter/dark energy, 199–201
evidence for, 29, 152–55, 157
potential recreation of the big bang, 166
when the big bang occurred, 30, 37, 47, 157
black holes, 149–50, 180, 182
Blake, William, xviii, 169
Bohr, Niels, 108, 207–8, 210, 211, 212
bonus particles, 77, 119, 191, 236–37
Borges, Jorge Luis, 166, 167
bosons, 174, 234–35
Brahe, Tycho, 7
brain processes, speeds and complexity of, 52–54, 58–60, 134–35, 138
See also human cognition; perception
carbon dating, 48–51
cellular biology and processes, 90–91
Cepheid variables, 27
change
fundamental laws as descriptions of, 63, 65, 122–25
and time, 46–47
change, particles of, 77, 234–36
charge, 73, 74, 77, 233–34
of atoms, 79
of specific particle types, 78, 81, 85, 235, 237
See also color charge; electric charge
chemistry and chemical processes
cellular biology and processes, 90–91
chemistry of material that emerged from the big bang, 155
femtochemistry and the speed of biochemical processes, 52, 54, 56–57, 59
and the fundamental laws, 120–21
imaging through x-ray diffraction patterns, 33–34
molecular complexity, 130–35
and radioactive dating, 48, 50
and spectroscopy, 109
See also atoms; molecules and molecular processes
chess, 204, 220
chi, 114
classical mechanics, 8
the dark matter problem, 194–96
as framework for later investigations, 94–96, 193–94
and GPS, 18, 19
Newtonian theory of gravity, 66–67, 94, 95, 114–15, 116, 117
See also motion; planetary motion and arrangements
Clay Foundation, 204
climate change, 140–41
clocks, 17, 18–19, 44, 47, 55–56, 68–69
CMB. See cosmic microwave background
cognitive processes, 52–54, 58–60
color charge, 84, 122–23, 234
of specific particle types, 78, 84, 85, 235, 237
color vision, 170–71
combinatorial explosion, 131–32
commutation relations. See quantum conditions
complementarity, 206–22
basic principles of, 206, 218–19
between human comprehensibility and accurate understanding, 220–21
between humility and self-respect, 221–22
and levels of description, 213–16
as mind expanding, 206–7, 218–19
in music and art, 216–17
quantum complementarity, 208–13
in science, 207–16
complexity, 160–67
dynamic complexity, 129–36
factors in the emergence of, 161–66
within simplicity, 160, 166–67, 189
computer games, 70–71
computer processes. See artificial intelligence; information flows and processing
construction, particles of, 77, 78–86
See also electrons; gluons; gravitons; photons; quarks
Copernicus, Nicolaus, 6
Core concept, 121–25
cosmic background radiation, 152, 154–55, 157, 162, 163, 200–201
cosmic distances, 42, 43
cosmic horizon, 28–31, 37–38
measuring, 23–28, 30–31, 198–99
cosmic energy abundance, 126–28
See also energy abundance
cosmic history, 145–59
and the cosmic horizon, 37–38
future investigations of, 156–59
inflation concept, 156–57, 162, 189
role of dark matter and dark energy, 199–200
scope and limits of, 146–48
See also big bang theory
cosmic microwave background (CMB), 154–55, 157, 162, 163, 200–201
cosmic rays, 236
cosmic strings, 166
cosmological constant (Einstein), 195, 197–98, 200
cosmology. See astronomy and cosmology; big bang theory; universe; entries beginning with “cosmic”
Coulomb’s law, 95, 105
Crick, Francis, 34, 225–26
Cronin, James, 190–91
Cubists, 217
Cummings, Ray, 44
dark energy, 188, 193, 195–96, 197–201
dark matter, 158–59, 166, 188, 193–97, 199–201, 237, 241
decay processes
and atomic spectra, 107
neutron decay, 118–19, 135
proton decay, 123, 166
radioactive dating, 47–51
Democritus, 72–73, 77
dendrochronology, 50
digital photography, 138
digital processes. See artificial intelligence; information flows and processing
Dirac, Paul, 100, 119–20, 122, 184
disequilibrium. See instability/disequilibrium
distances and distance measurement
cosmic horizon, 28–31, 37–38
distance and the strengths of the fundamental forces, 112, 123–24
measuring cosmic distances, 23–28, 30–31, 198–99
quantum distance fluctuations, 40
subatomic and interatomic distances, 33, 39–40, 56
and time, 20, 30
See also asymptotic freedom; size and scale
DNA and DNA sequences, 34, 131–32
dogs, 169
Doppler effect, 28
Dragon’s Egg (Forward), 59
dynamic complexity, 129–36
and combinatorial explosion, 131–32
examples of, 129–30
of human brain processes, 134–35, 138
nonchemical platforms for, 137–39
and provisional stability, 132–34
solar energy as fuel for, 127–28, 133–34, 135–36, 163
Dyson spheres, 127, 165
Earth
age of, 50–51, 52
and the cosmic distance ladder, 23–24, 25
size of, 23, 24
surface temperature of, 133–34, 140–41
economic growth. See human activities and purposes
Einstein, Albert, 44, 210
Bohr-Einstein debates, 212
on Bohr’s work, 108, 208
on human exceptionalism, 226–27, 228
light-quanta hypothesis, 82–83, 99, 100–101, 107
on scientific understanding, xii
on simplicity, 148
and unified field theory, 123–24
views on complementarity, 211–12
See also general relativity; special relativity
electric charge, 84, 95, 233–34
of atomic nuclei, 79
of holes, 87–88
of specific particle types, 78, 81–82, 84, 85, 112, 235, 237
electric force and field, 95, 99–100, 105
electromagnetic force and field, 84, 95–102, 103, 233
Maxwell’s equations, 97–98, 99–100, 178, 189, 234
and time reversal, 189
See also QED
electromagnetic waves, 178–79
electrons
and atomic structure, 62, 78–79, 83, 105–7, 108–9
behavior and properties of, 75, 78–82, 84, 101–2
in digital processes, 54, 59, 138–39
as products of decay processes, 48, 49, 118, 119
and quasiparticles, 87, 89
elementary particles
axions, 122, 159, 166, 201–2
basic influences of the fundamental forces on, 103–4, 121–22
bonus particles, 77, 119, 191, 236–37
dark matter constituents, 200, 201–2
designer particles and smart materials, 87–92
Higgs particle, 57, 175–78, 234–35, 236
particles of change, 77, 234–36
particles of construction, 77, 78–86
properties of, 72–76, 77, 231–34
See also specific particle types
Eliot, T. S., 53–54
emergent properties, 214–15
empathy, and scientific understanding, 227–28
End of Science, 216
energy
dark energy, 188, 193, 195–96, 197–201
and the existence of fields, 97
human energy use and sources, 126–27, 140–41, 165–66
and inertia and gravity, 117, 232
latent energy, 113, 166
and mass, 85, 113–14, 115, 117, 231, 232
powering of stars, 113, 135–36, 163, 165, 166, 235
related properties of quasiparticles, 90
energy abundance, xiv, 126–30, 136, 165–66
equilibrium/disequilibrium
gravitational instability, 149–51, 156, 161–62, 164, 189
thermal equilibrium, 151, 163
See also provisional stability
Euclid, 39
Euclidean geometry, 15–21, 39, 40
geometry of space, 38, 151, 156–57, 240–41
space-time as geometric object, 116, 151, 156
Faraday, Michael, xiii, 95–96, 97, 98–99, 178
femtochemistry, 56–57, 59
Feynman, Richard, xiv, 61–62, 184
fields, 67, 95–102
nineteenth-century work on, 95–99, 105, 178
quantum fields, 99–102
See also specific field types
Fitch, Val, 190–91, 203
forces. See fundamental forces; specific forces
Forward, Robert, 59
fossil fuels, 140
FQHE (fractional quantum Hall effect), 89
Franklin, Benjamin, 81–82
Franklin, Rosalind, 34
free will, 217, 218
Freund, Peter, 75–76
fundamental forces, 102, 103–5, 120–21
Core concept and unified field theory, 121–25
and dynamic complexity, 136
See also specific forces
fundamental laws
and co
mplementarity, 213–14, 216
Core concept, 121–25
envisioning universes in which they do not hold, 70–72
as foundation of practical physics, 119–22
vs. human laws, 93–94
locality principle, 63–64, 65, 66–67, 68–69, 96, 102, 191
Newton’s work, 8, 66–67
principles of, 63–66
spectroscopy’s confirmation of, 109
and time reversal, 148–49, 188–92
universality of, 21, 38–39, 63, 65
See also classical mechanics; specific laws
fundamental properties of matter, 72–77, 86, 231–34
See also charge; mass; spin
galaxies
galactic motion as evidence of the universe’s expansion, 28–31, 145–46, 149–50, 153–54, 165
gravitational lensing of light from, 196–97
properties and distribution of, 22, 27, 30, 150, 196
Galilei, Galileo, xiii, 7, 8, 55
Galois, Évariste, 52
gamma rays, 83, 98, 182
Gauss, Carl Friedrich, 16, 21
GDP, 3
Geiger, Hans, 35–37, 56
Gell-Mann, Murray, 111
general laws. See fundamental laws
general relativity, 20, 57, 86, 195
basic principles of, 115–17
and the character of space, 39–40, 57, 116–17, 240–41
cosmological constant, 195, 197–98, 200
and gravitational lensing, 197
and Mercury’s motion, 195
See also gravitational waves; gravity
genetic engineering, 222
geometry. See Euclidean geometry
Global Positioning System (GPS), 16–19
gluons, 62, 121, 151
behavior and properties of, 78, 83–84, 85, 114, 238, 239
and color charge, 84, 234
jets as avatars of, 238–40
Go, 220
GPS (Global Positioning System), 16–19
gravitational wave detectors, 21
gravitational waves, 178–82
gravitons, 85–86, 157–58
gravity, 114–17
and complexity, 136, 161–62
as fundamental force, 103
gravitational instability, 149–51, 156, 161–62, 164, 189
gravitational lensing, 196–97
Newtonian theory of, 66–67, 94, 95, 114–15, 116, 117
and the origins of the universe, 149–51, 152, 153, 156, 200