1 HOW TO BUILD A UNIVERSE
NO MATTER HOW hard you try you will never be able to grasp just how
tiny, how spatially unassuming, is a proton. It is just way too small.
A proton is an infinitesimal part of an atom, which is itself of course
an insubstantial thing. Protons are so small that a little dib of ink
like the dot on this i can hold something in the region of
500,000,000,000 of them, rather more than the number of seconds
contained in half a million years. So protons are exceedingly
microscopic, to say the very least.
Now imagine if you can (and of course you can't) shrinking one of those
protons down to a billionth of its normal size into a space so small
that it would make a proton look enormous. Now pack into that tiny, tiny
space about an ounce of matter. Excellent. You are ready to start a
I'm assuming of course that you wish to build an inflationary universe.
If you'd prefer instead to build a more old-fashioned, standard Big Bang
universe, you'll need additional materials. In fact, you will need to
gather up everything there is-every last mote and particle of matter
between here and the edge of creation-and squeeze it into a spot so
infinitesimally compact that it has no dimensions at all. It is known as
In either case, get ready for a really big bang. Naturally, you will
wish to retire to a safe place to observe the spectacle. Unfortunately,
there is nowhere to retire to because outside the singularity there is
no where. When the universe begins to expand, it won't be spreading out
to fill a larger emptiness. The only space that exists is the space it
creates as it goes.
It is natural but wrong to visualize the singularity as a kind of
pregnant dot hanging in a dark, boundless void. But there is no space,
no darkness. The singularity has no "around" around it. There
is no space for it to occupy, no place for it to be. We can't even ask
how long it has been there-whether it has just lately popped into being,
like a good idea, or whether it has been there forever, quietly awaiting
the right moment. Time doesn't exist. There is no past for it to emerge
And so, from nothing, our universe begins.
In a single blinding pulse, a moment of glory much too swift and
expansive for any form of words, the singularity assumes heavenly
dimensions, space beyond conception. In the first lively second (a
second that many cosmologists will devote careers to shaving into
ever-finer wafers) is produced gravity and the other forces that govern
physics. In less than a minute the universe is a million billion miles
across and growing fast. There is a lot of heat now, ten billion degrees
of it, enough to begin the nuclear reactions that create the lighter
elements-principally hydrogen and helium, with a dash (about one atom in
a hundred million) of lithium. In three minutes, 98 percent of all the
matter there is or will ever be has been produced. We have a universe.
It is a place of the most wondrous and gratifying possibility, and
beautiful, too. And it was all done in about the time it takes to make a
When this moment happened is a matter of some debate. Cosmologists have
long argued over whether the moment of creation was 10 billion years ago
or twice that or something in between. The consensus seems to be heading
for a figure of about 13.7 billion years, but these things are
notoriously difficult to measure, as we shall see further on. All that
can really be said is that at some indeterminate point in the very
distant past, for reasons unknown, there came the moment known to
science as t = 0. We were on our way.
There is of course a great deal we don't know, and much of what we think
we know we haven't known, or thought we've known, for long. Even the
notion of the Big Bang is quite a recent one. The idea had been kicking
around since the 1920s, when Georges Lem tre, a Belgian priest-scholar,
first tentatively proposed it, but it didn't really become an active
notion in cosmology until the mid-1960s when two young radio astronomers
made an extraordinary and inadvertent discovery.
Their names were Arno Penzias and Robert Wilson. In 1965, they were
trying to make use of a large communications antenna owned by Bell
Laboratories at Holmdel, New Jersey, but they were troubled by a
persistent background noise-a steady, steamy hiss that made any
experimental work impossible. The noise was unrelenting and unfocused.
It came from every point in the sky, day and night, through every
season. For a year the young astronomers did everything they could think
of to track down and eliminate the noise. They tested every electrical
system. They rebuilt instruments, checked circuits, wiggled wires,
dusted plugs. They climbed into the dish and placed duct tape over every
seam and rivet. They climbed back into the dish with brooms and
scrubbing brushes and carefully swept it clean of what they referred to
in a later paper as "white dielectric material," or what is
known more commonly as bird shit. Nothing they tried worked.
Unknown to them, just thirty miles away at Princeton University, a team
of scientists led by Robert Dicke was working on how to find the very
thing they were trying so diligently to get rid of. The Princeton
researchers were pursuing an idea that had been suggested in the 1940s
by the Russian-born astrophysicist George Gamow that if you looked deep
enough into space you should find some cosmic background radiation left
over from the Big Bang. Gamow calculated that by the time it crossed the
vastness of the cosmos, the radiation would reach Earth in the form of
microwaves. In a more recent paper he had even suggested an instrument
that might do the job: the Bell antenna at Holmdel. Unfortunately,
neither Penzias and Wilson, nor any of the Princeton team, had read
The noise that Penzias and Wilson were hearing was, of course, the noise
that Gamow had postulated. They had found the edge of the universe, or
at least the visible part of it, 90 billion trillion miles away. They
were "seeing" the first photons-the most ancient light in the
universe-though time and distance had converted them to microwaves, just
as Gamow had predicted. In his book The Inflationary Universe, Alan Guth
provides an analogy that helps to put this finding in perspective. If
you think of peering into the depths of the universe as like looking
down from the hundredth floor of the Empire State Building (with the
hundredth floor representing now and street level representing the
moment of the Big Bang), at the time of Wilson and Penzias's discovery
the most distant galaxies anyone had ever detected were on about the
sixtieth floor, and the most distant things-quasars-were on about the
twentieth. Penzias and Wilson's finding pushed our acquaintance with the
visible universe to within half an inch of the sidewalk.
Still unaware of what caused the noise, Wilson and Penzias phoned Dicke
at Princeton and described their problem to him in the hope that he
might suggest a solution. Dicke realized at once what the two young men
had found. "Well, boys, we've just been scooped," he told his
colleagues as he hung up the phone.
Soon afterward the Astrophysical Journal published two articles: one by
Penzias and Wilson describing their experience with the hiss, the other
by Dicke's team explaining its nature. Although Penzias and Wilson had
not been looking for cosmic background radiation, didn't know what it
was when they had found it, and hadn't described or interpreted its
character in any paper, they received the 1978 Nobel Prize in physics.
The Princeton researchers got only sympathy. According to Dennis Overbye
in Lonely Hearts of the Cosmos, neither Penzias nor Wilson altogether
understood the significance of what they had found until they read about
it in the New York Times.
Incidentally, disturbance from cosmic background radiation is something
we have all experienced. Tune your television to any channel it doesn't
receive, and about 1 percent of the dancing static you see is accounted
for by this ancient remnant of the Big Bang. The next time you complain
that there is nothing on, remember that you can always watch the birth
of the universe.
Although everyone calls it the Big Bang, many books caution us not to
think of it as an explosion in the conventional sense. It was, rather, a
vast, sudden expansion on a whopping scale. So what caused it?
One notion is that perhaps the singularity was the relic of an earlier,
collapsed universe-that we're just one of an eternal cycle of expanding
and collapsing universes, like the bladder on an oxygen machine. Others
attribute the Big Bang to what they call "a false vacuum" or
"a scalar field" or "vacuum energy"-some quality or
thing, at any rate, that introduced a measure of instability into the
nothingness that was. It seems impossible that you could get something
from nothing, but the fact that once there was nothing and now there is
a universe is evident proof that you can. It may be that our universe is
merely part of many larger universes, some in different dimensions, and
that Big Bangs are going on all the time all over the place. Or it may
be that space and time had some other forms altogether before the Big
Bang-forms too alien for us to imagine-and that the Big Bang represents
some sort of transition phase, where the universe went from a form we
can't understand to one we almost can. "These are very close to
religious questions," Dr. Andrei Linde, a cosmologist at Stanford,
told the New York Times in 2001.
The Big Bang theory isn't about the bang itself but about what happened
after the bang. Not long after, mind you. By doing a lot of math and
watching carefully what goes on in particle accelerators, scientists
believe they can look back to 10-43 seconds after the moment of
creation, when the universe was still so small that you would have
needed a microscope to find it. We mustn't swoon over every
extraordinary number that comes before us, but it is perhaps worth
latching on to one from time to time just to be reminded of their
ungraspable and amazing breadth. Thus 10-43 is
0.0000000000000000000000000000000000000000001, or one 10 million
trillion trillion trillionths of a second.
Most of what we know, or believe we know, about the early moments of the
universe is thanks to an idea called inflation theory first propounded
in 1979 by a junior particle physicist, then at Stanford, now at MIT,
named Alan Guth. He was thirty-two years old and, by his own admission,
had never done anything much before. He would probably never have had
his great theory except that he happened to attend a lecture on the Big
Bang given by none other than Robert Dicke. The lecture inspired Guth to
take an interest in cosmology, and in particular in the birth of the
The eventual result was the inflation theory, which holds that a
fraction of a moment after the dawn of creation, the universe underwent
a sudden dramatic expansion. It inflated-in effect ran away with itself,
doubling in size every 10-34 seconds. The whole episode may have lasted
no more than 10-30 seconds-that's one million million million million
millionths of a second-but it changed the universe from something you
could hold in your hand to something at least
10,000,000,000,000,000,000,000,000 times bigger. Inflation theory
explains the ripples and eddies that make our universe possible. Without
it, there would be no clumps of matter and thus no stars, just drifting
gas and everlasting darkness.
According to Guth's theory, at one ten-millionth of a trillionth of a
trillionth of a trillionth of a second, gravity emerged. After another
ludicrously brief interval it was joined by electromagnetism and the
strong and weak nuclear forces-the stuff of physics. These were joined
an instant later by swarms of elementary particles-the stuff of stuff.
From nothing at all, suddenly there were swarms of photons, protons,
electrons, neutrons, and much else-between 1079 and 1089 of each,
according to the standard Big Bang theory.
Such quantities are of course ungraspable. It is enough to know that in
a single cracking instant we were endowed with a universe that was
vast-at least a hundred billion light-years across, according to the
theory, but possibly any size up to infinite-and perfectly arrayed for
the creation of stars, galaxies, and other complex systems.
What is extraordinary from our point of view is how well it turned out
for us. If the universe had formed just a tiny bit differently-if
gravity were fractionally stronger or weaker, if the expansion had
proceeded just a little more slowly or swiftly-then there might never
have been stable elements to make you and me and the ground we stand on.
Had gravity been a trifle stronger, the universe itself might have
collapsed like a badly erected tent, without precisely the right values
to give it the right dimensions and density and component parts. Had it
been weaker, however, nothing would have coalesced. The universe would
have remained forever a dull, scattered void.
This is one reason that some experts believe there may have been many
other big bangs, perhaps trillions and trillions of them, spread through
the mighty span of eternity, and that the reason we exist in this
particular one is that this is one we could exist in. As Edward P. Tryon
of Columbia University once put it: "In answer to the question of
why it happened, I offer the modest proposal that our Universe is simply
one of those things which happen from time to time." To which adds
Guth: "Although the creation of a universe might be very unlikely,
Tryon emphasized that no one had counted the failed attempts."
Martin Rees, Britain's astronomer royal, believes that there are many
universes, possibly an infinite number, each with different attributes,
in different combinations, and that we simply live in one that combines
things in the way that allows us to exist. He makes an analogy with a
very large clothing store: "If there is a large stock of clothing,
you're not surprised to find a suit that fits. If there are many
universes, each governed by a differing set of numbers, there will be
one where there is a particular set of numbers suitable to life. We are
in that one."
Rees maintains that six numbers in particular govern our universe, and
that if any of these values were changed even very slightly things could
not be as they are. For example, for the universe to exist as it does
requires that hydrogen be converted to helium in a precise but
comparatively stately manner-specifically, in a way that converts seven
one-thousandths of its mass to energy. Lower that value very
slightly-from 0.007 percent to 0.006 percent, say-and no transformation
could take place: the universe would consist of hydrogen and nothing
else. Raise the value very slightly-to 0.008 percent-and bonding would
be so wildly prolific that the hydrogen would long since have been
Excerpted from "A Short History of Nearly Everything" by Bill Bryson. Copyright © 2004 by Bill Bryson. Excerpted by permission. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher. Excerpts are provided solely for the personal use of visitors to this web site.