A BRIEFER HISTORY OF TIME | BY STEPHEN HAWKINGS

A Briefer History of Time is a 2006 popular-science book by the English physicist Stephen Hawking and the American physicist Leonard Mlodinow.
A Briefer History of Time : AUTHORS
Stephen William Hawking (8 January 1942 – 14 March 2018) was an English theoretical physicist, cosmologist, and author who was director of research at the Centre for Theoretical Cosmology at the University of Cambridge at the time of his death. He was the Lucasian Professor of Mathematics at the University of Cambridge between 1979 and 2009.
A Briefer History of Time : OVERVIEW
The book is an update and rewrite of Hawking's 1988 A Brief History of Time. In this book Hawking and Mlodinow present quantum mechanics, string theory, the big bang theory, and other topics in a more accessible fashion to the general public. The book is updated with newly discovered topics, and informs of recurring subjects throughout the book in greater details.
A Briefer History of Time : CHAPTERS
1.QUANTUM FLUCTUATION
In Which Our Universe Begins
2.INFLATION
In Which the Grand Unified Force Separates into the Four Forces of Nature We Now, Know Them, and the Universe Expands to Many Times Its Original Size in a Very Short Period of Time .
3.EXPANSION
In Which the Universe Continues to Expand, though not Quite as Quickly.
4.PARTICLE-ANTIPARTICLE ANNIHILATION
5.DEUTERIUM AND HELIUM PRODUCTION
In Which Many of the Protons and Neutrons in the Early Universe Combine to Form Heavy Hydrogen and Helium .
6.RECOMBINATION
In Which Electrons Combine with Hydrogen and Helium Nuclei, Producing Neutral Atoms
7.GALAXY FORMATION
In Which the Milky Way Galaxy Forms
8.TURBULENT FRAGMENTATION
In Which a Giant Cloud of Gas Fragments into Smaller Clouds,Which Become
9.MASSIVE STAR FORMATION
In Which a Massive Star Is Formed
10.STELLAR EVOLUTION
In Which Stars Evolve and Eventually Die
11.IRON PRODUCTION
In Which Iron Is Produced in the Core of a Massive Star, Resulting in Disaster.
12.SUPERNOVA EXPLOSION
In Which a Massive Star Ends Its Life by Exploding
13.STAR FORMATION
In Which the Sun Forms
In Which the Sun Forms
14.PLANETARY DIFFERENTIATION
In Which the Planet Earth Forms
15.VOLATILE GAS EXPULSION
In Which the Atmosphere of the Earth Is Produced
16.MOLECULAR REPRODUCTION
In Which Life on Earth Begins
17.PROTEIN CONSTRUCTION
In Which Proteins Are Made from Amino Acids
18.FERMENTATION
In Which Bacteria Obtain Energy from Their Surroundings
19.CELL DIFFERENTIATION
In Which Eukaryotic Life Arises
In Which Eukaryotes Evolve to Survive in an Atmosphere with Increasing Amounts of Oxygen
21.MULTICELLULAR ORGANISMS
In Which Organisms Composed of Multiple Cells Arise
22.SEXUAL REPRODUCTION
In Which a New Form of Reproduction Occurs
In Which the Diversity of Life Forms on Earth Increases Greatly in a Relatively Short Time
24.TRILOBITE DOMINATION
In Which Trilobites Rule the Earth
In Which Animals First Venture Onto Land
26.COMET COLLISION
In Which a Comet Hits the Earth
27.DINOSAUR EXTINCTION
In Which the Dinosaurs Die
28.MAMMAL EXPANSION
In Which Many Species of Mammals Develop
29.HOMO SAPIENS MANIFESTATION
In Which Modern Human Beings Appear
30.LANGUAGE ACQUISITION
In Which Human Beings Develop Spoken Language
31.GLACIATION
In Which a Thousand-Year Ice Age Begins
32.INNOVATION
In Which Advanced Tools Are Widely Used
33.RELIGION
In Which a Diversity of Beliefs Arise
34.ANIMAL DOMESTICATION
In Which Humans Domesticate Animals
35.FOOD SURPLUS PRODUCTION
In Which Humans Develop Agriculture
36.INSCRIPTION
In Which Writing Is Invented
37.WARRING NATIONS
In Which Nation Battles Nation for Resources
38.EMPIRE CREATION AND DESTRUCTION
In Which the First Empire in Human History Comes and Goes
39.CIVILIZATION
In Which Many and Sundry Events Occur
40.CONSTITUTION
In Which a Constitution Is Written
41.INDUSTRIALIZATION
In Which Automated Manufacturing and Agriculture Revolutionize the World
42.WORLD CONFLAGRATIONS
In Which Most of the World Is at War
43.FISSION EXPLOSIONS
In Which Humans Develop NuclearWeapons
44.COMPUTERIZATION
In Which Computers Are Developed
45.SPACE EXPLORATION
In Which Humans Begin to Explore Outer Space
46.POPULATION EXPLOSION
In Which the Human Population of the Earth Increases at a Very Rapid Pace
47.SUPERPOWER CONFRONTATION
In Which Two Powerful Nations Risk it All
48.INTERNET EXPANSION
In Which a Network of Computers Develops
49.RESIGNATION
In Which One Human Quits His Job
50.REUNIFICATION
In Which a Wall Goes Up and Then Comes Down
51.WORLD WIDE WEB CREATION
In Which a New Medium Is Created
52.COMPOSITION
In Which a Book Is Written
53.EXTRAPOLATION
In Which Future Events Are Discussed
54.COMPENDIOUS GLOSSARY
In Which Familiar and Unfamiliar Terms Are Defined
A Briefer History of Time : PREVIEW
1.QUANTUM FLUCTUATION
In Which Our Universe Begins
Once upon a time, long ago and far away, there was a universe very much like our own. It had dogs, and cats, and people (some of whom preferred the dogs and some of whom preferred the cats), and Trigoencephalopodic Gnoccis, and
degrees Fahrenheit. It immediatelybegan to expand, become less dense, and cool off.Luckily for the inhabitants of the first universe, the new universe quickly became detached from the old universe and started expanding into a completely
different four-dimensional volume of space.This is the story of that Universe, and of some of the things that have happened in it during the last 14 billion years.
2.QUANTUM INFLATION
In Which
the Grand Unified Force Separates into the Four Forces of Nature as We Now know Them,and the Universe Expands to Many Times, Its Original Size in a Very Short,Its Original Size in a Very Short period of time.
“In the starting position it's Gravity, next is Strong Nuclear, Weak Nuclear, and finally a young filly named Electromagnetism.All four forces are lined up and unified at the starting gate, waiting for the bell to announce the moment of the Big Bang, which will start
this exciting race to determine which is the strongest force in the Universe.
“There's the starting bell, and they're off!
“At 10-43 seconds it's Weak Nuclear neck and neck with Electromagnetism and Strong Nuclear, with Gravity bringing up the rear.
“It's still a little early in the race folks, just 10-38 seconds, but it looks like Strong Nuclear might be making its move. Yes, at 10-37seconds Strong Nuclear has broken away from Electromagnetism and Weak Nuclear! The energy density isastounding, ladies and gentlemen, the Universe is expanding exponentially! This is turning out to be a real donnybrook!!
“We're at 10-36 seconds and it's still going. 10-35 seconds. 10-34seconds....
“Oh wait…what's this? It's 10-33 seconds and I think... I think... yes indeed, ladies and gentlemen! The transition to broken symmetry is complete at 10-32 seconds.
“Strong Nuclear is now about fourteen times stronger than Electromagnetism, and the Universe is more than a billion billion billion billion billion billion times larger than it was at 10-37seconds.
The crowd is going wild, they're throwing their sombreros into the air and shouting, “Higgs! Higgs! Higgs!”* Such a magnificent showing by Strong Nuclear! What a force!”
*The four forces separated through a process called “spontaneous symmetry-breaking,” caused by a “Higgs field,” whose “potential” is sort of “sombrero-shaped.” While the fundamental particle physicists frown at the lack of precision in this explanation, the rest of us may continue on to the next chapter, which discusses parking place.
3.EXPANSION
In Which the Universe Continues to Expand,though not Quite as Quickly
The Universe is expanding, but for some reason it never gets any easier to find a parking place. There are a couple of reasons for this. First, the Universe is expanding very slowly: You would have
to wait 65 million years for a one-mile block in the middle of space to expand enough to produce another parking space. The other reason is that the gravitational attraction between all of the particles in the Earth completely overcomes the expansion of the Universe, so even if you circled a block on Earth for 65 million years it wouldn't get any bigger. Taking public transportation would be a much more efficient use of your time.
But if the Universe is expanding, what is it expanding into? In order to answer that question, let us imagine ourselves to be two-dimensional creatures living on the surface of a balloon. The only directions we know are backwards/forwards and right/left. Only the mathematicians among us have any concept of up/down, and everyone else suspects that they are probably just making it up. Eventually however, some two-dimensional astronomers discover that the balloon is expanding. How could that be? To an outside–
that is to say, three-dimensional–observer it would be obvious: the balloon is increasing in volume and the surface of the balloon–the
two-dimensional “universe”–is increasing in area. However, these concepts are quite difficult for the two-dimensional inhabitants of balloonland.
So am I saying that our Universe is like a three-dimensional balloon expanding into a four-dimensional space? Well...maybe. But that would imply the Universe has a finite volume–astronomers call this type of universe “closed”–and will eventually stop expanding and begin to recollapse. While this is possible, many astronomers now consider it to be unlikely.
So what is the Universe really like? It appears most likely that the Universe is infinite in extent–“open”–and will continue to expand forever, which implies that it is a three-dimensional hyperbolic paraboloid in four-dimensional space. Think of it as the four-dimensional representation of a three-dimensional saddle. Or, better yet, try not to worry about it at all. It won’t make it any easier to find a parking place.
4.PARTICLE-ANTIPARTICLE ANNIHILATION
In Which All the Antiparticles in the Universe Annihilate Almost All the Particles, Creating a Universe Made Up of Matter and Photons
THE FIRST BOOK OF GAMOV, CALLED
ORIGINS
CHAPTER 1, in which the Universe is transformed
In the beginning, God created the particles and the antiparticles.aNow the temperature was high, and the particles and the antiparticles were in equilibrium, and the Spirit of God was hoveringb over the Universe.
a Antiparticles are very much like particles, except that when particles and antiparticles meet they completely destroy each other and emit a burst of energetic radiation. b In a four dimensional sense; God does move in mysterious ways sometimes.
ORIGINS, 1
2.And God said, “Let there be light,” and some particles and antiparticles annihilated each other to produce photons, and there was light. God saw that the light was good, and He separated the photons from the particles and antiparticles. God called the photons “bosons” and the particles and antiparticles He called “fermions.”c
And there was pair production and there was photon creation–the first 10-43 seconds.
3.And God said, “Let there be an exponential expansion of the Universe to separate one part from another.” So God made an exponential expansion of the Universe that separated the magnetic
monopoles from each other so that all attempts to find one would be futile. And it was so. God called the exponential expansion “inflation.” And there was vacuum energy density and there was
inflation–the first 10-32 seconds.
4.And God said, “Let the antiparticles and the particles be gathered together, and let photons appear.” And it was so. God called the few remaining particles “matter,”and the annihilated antiparticles He called “antimatter.” And God saw that it was good. And there were neutrons and there were protons–the first second.
5.And God said, “Let there be nuclear reactions to produce heavier elements.” And it was so. God made protons and neutrons combine to produce deuterium nuclei, and the deuterium nuclei He combined to make helium nuclei. And there was also some lithium and there was also some beryllium–the first three minutes.
c He called some of the particles and antiparticles bosons as well, but that’s another story.
ORIGINS, 1
6. And God said, “Let the Universe teem with energetic photons, and let electrons fly past atomic nuclei.” And it was so. God blessed the particles and said, “Be fruitful and produce neutral atoms,” and the radiation became less energetic and the electrons combined with atomic nuclei. And God saw that it was good. And there was background radiation and there were neutral atoms–the first 380,000 years.
7.And God said, “Let the density perturbations produce collections of matter according to their kinds: stars, galaxies, and clusters of galaxies, each according to its kind." And it was so.
God made the clusters of galaxies according to their kinds, and the galaxies according to their kinds, and the stars according to their kinds. And God saw that it was good.
8.Then God said, “Let us make gravity in our image, in our likeness, and let it rule over the superclusters of galaxies, over the clusters of galaxies, over the groups of galaxies, over the galaxies, over the clusters of stars, and over the solar systems.”
9.God saw all that He had made, and it was very good. And there was violent relaxation and virialization–the first billion years.
10.By the first billion years God had finished the work He had been doing; so after the first billion years He rested from all His work. And God blessed the remaining time in the Universe, and made it holy, because during it He rested from all the work of creating that He had done.
5.DEUTERIUM AND HELIUM PRODUCTION
In Which Many of the Protons and Neutrons in the Early Universe Combine to Form Heavy Hydrogen and Helium
The Taming of the Sneutrino
THE PERSONS OF THE PLAY
PETRUCHIO, a proton
GRUMIO, a neutron
PETRUMIO, a deuteron
HORTENSIO, a deuteron
PETRUMSIO, a helium nucleus
ACT 1
Scene 1: Padua. A public place. Before the spatial domain of HORTENSIO.
Enter PETRUCHIO and GRUMIO
PETRUCHIO Verona, for a while I take my leave, To see my friends in Padua; but, of all, My best belovéd and approvéd friend,
Hortensio; and I trow this is his spatial domain— Here, sirrah Grumio; knock, I say.
GRUMIO Knock, sir! whom should I knock? is there any particle has rebused your worship?
PETRUCHIO Villain, I say, knock me here soundly.
GRUMIO Knock you here, sir? why, sir, what am I, sir, that I should knock you here, sir? 10
PETRUCHIO Villain, I say, knock me at this energy barrier, And rap me well, or I'll knock your knave's hair.
GRUMIO tunnels through PETRUCHIO’s energy barrier, producing PETRUMIO, a deuteron
Enter HORTENSIO
HORTENSIO. How now! what's the matter? My old friend Grumio and my good friend Petruchio! How came you from Verona and into Petrumio?
PETRUMIO tunnels through HORTENSIO's energy barrier, producing PETRUMSIO, a helium nucleus.
Exit PETRUMSIO
6.GALAXY FORMATION
“All the News Prices may vary in areas
from Everywhere” outside the Local Supercluster
THE DAILY UNIVERSE
MONDAY, JUNE 21, 10,000,000,000 B.C.
MAJOR GALAXY FORMS IN UNFASHIONABLE CLUSTER
Could life develop there?
LOCAL GROUP, 10 billion years B.C.—Another major galaxy formed today in the Local Group, a collection of about two dozen galaxies located on the outskirts of the large Virgo Cluster
of Galaxies. The new spiral galaxy has a mass of 500 billion solar masses (about 2 million billion billion billion billion pounds) and a diameter of 100,000 light-years (a little less than a billion billion
miles). It is the second large galaxy to form in the Local Group in the past 100 million years. Whether life will develop within either of these galaxies is still an open question.
“The first stars formed just after the pregalactic cloud began to collapse, and many of them reside in one of the hundreds of globular clusters in the new galaxy,” one observer reported.
Globular clusters contain hundreds of thousands of stars and orbit the new galaxy along elliptical paths. The stars here are mostly hydrogen and helium so it is not expected that many planets will
form, making it unlikely for life to arise around these stars.
As the pregalactic cloud began to collapse in earnest, the cloud's slight rotation became faster and faster and the stars and gas formed a disk.
“This thin layer of stars and gas looks like a phonograph record and is rotating around the center of the galaxy at a speed of about half a million miles per hour,” says another expert. It is expected that the intense star formation in this region of the new galaxy will result in large amounts of the elements needed to form planets and life.
The chances for life may be highest near the center of the galaxy, where the star formation is most intense. However, it is
possible that supernova explosions will sterilize planets that orbit stars close to the center of the galaxy. When asked to rate the chances of the first life in this galaxy arising as far away as 30,000 light-years from the center of the galaxy, one expert estimated the probability to be “absurdly small.”



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