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construct cosmologies. A multitude of fine origin tales suggest them-
selves, but they can’t all be true. How do we choose? We can test our
answers against the nature of nature itself.
The tale of Cosmic Evolution is our new origin story. Over the past
four hundred years, we’ve found some answers, at least partial and pro-
visional ones, to many of our oldest questions: “How did the world
begin, and when?” “How does life work?” “Who were the first
humans?” “What are the heavens made of, and how are they related
to us?” Once these may have seemed to be disconnected, independent
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mysteries. Now we’ve found that the answers can all be woven together
into one continuous chronicle: our journey from universal birth
through galaxies, stars and planets, elements, molecules, and life, into
mind, and then, perhaps, onward to something beyond.
This story has not been handed down, but dug up and cobbled
together. It is full of holes, inconsistencies, and paradox. An inex-
haustible stream of new evidence ensures that it is a living myth, a
script always in rewrite. Paradoxically, this provisional and changing
nature of the story of Cosmic Evolution is what gives it its great credi-
bility. We see it improving before our very eyes, admitting error and
making corrections. It’s getting so much better all the time.
What do I mean when I say this is “our” origin story? Just whom am
I referring to? A bunch of males who are not only dead but white? Is
this story accepted and embraced by everyone? Of course not. But our
knowledge of Cosmic Evolution is not in conflict with the core beliefs
of most of the religions, and it certainly isn’t necessary to discard or
discredit older origin stories to embrace this new one. Even if you go to
church, temple, or ashram for the singing and the dancing (that’s the
part I like), for the comfort of spiritual community, or to receive
ancient wisdom, you probably accept that science has clued us in to
some big truths about our origins that the writers of our ancient texts
could not have known. Except for some Rastas I used to play with in a
reggae band, and some Jehovah’s Witnesses who’ve knocked on my
door, I haven’t met many people who take a seven-day Genesis literally.
Clearly, if our society endorses any “official” story of genesis, it is the
scientific account. It is the most generally accepted origin scenario in
our culture, and the one we teach in public schools, when we bother to
teach about origins at all. Strange, isn’t it, that science has become the
keeper of official wisdom? Since Galileo’s time, science has grown from
an upstart, radical fringe to a dominant worldview. To punish us for
our contempt for authority, fate made us secular priests with pocket
protectors.
Yet, the story of Cosmic Evolution itself is not well-known or widely
celebrated. This new creation story is typically regarded as an impres-
sive work that is quite incomprehensible to nonexperts. Most people do
not look to this story for vital beliefs and satisfying answers to deep
questions. Rather, they think of it as science. Many people associate sci-
ence with a dry recitation of facts or torture by algebra while waiting
for the clock to signal freedom from incarceration. So here we’ve found
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what seem to be convincing clues to our real origins, a story about a
point of nothingness exploding and evolving over billions of years to
generate our entire universe of galaxies and flowers, and many regard
the tale as Dullsville. Maybe we’re not telling it in the right way.
Part of the problem is that an ethos running deep within our profes-
sion suggests that science, to be objective, must be devoid of passion.
The conduct of research does require a dispassionate attitude. When we
do science, we have to practice nonattachment. To keep ourselves hon-
est, we have to pretend not to care and always be willing to accept
nature’s verdict on our precious theories.
But we’ve spent too much time in the lab, and something has gone
wrong. This necessary emotional distance has led to a Spock-like
detachment in the way we share science with the rest of the world. It’s
all too easy to lapse into a science-class drone when telling the story of
Cosmic Evolution—the same, almost obligatory dry tone in which it
was taught to us. When we discover something fantastic about the age
of the Earth, the history of life, or our true location among the stars
and galaxies, we should be shouting it out with glee, not droning on
with only dim life signs. Why aren’t we singing the song of the galaxies
on television and doing the DNA dance in every town square?
Certainly Cosmic Evolution is the story I was brought up to believe,
but I’ve also studied enough of the evidence that now I think my con-
tinuing belief represents more than the tendency to retain the views of
one’s parents. It wasn’t exactly Fiddler on the Roof in our household,
but in my upbringing as a secular humanist Jewish American, I did
learn some of the traditional stories. Each year, we held a Passover
seder with a gathering of relatives and friends and recited the
Haggadah, the tale of the escape of the Jewish people from slavery, as
the kids and some adults fidgeted in eager anticipation of matzo ball
soup. I suppose the association with good food is part of the secret of
the success of this ritual—whose story has survived intact for thou-
sands of years, much of that time primarily as oral history. Maybe what
the story of Cosmic Evolution needs is a similar association with a fam-
ily gathering and an enticing hot meal.
Though I was deprived of (or saved from) spending my Sundays
learning the tale of Genesis, I picked up the basics later on. Genesis, like
many other prescientific takes on our origins, contains a kind of tempo-
ral anthropocentrism: not only are humans the focus and the crown of
creation, but the universe itself is only 5,775 years old. Thus the entire
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scope of all existence is held to be not much longer than the time during
which people have been walking the Earth (five days longer according
to Torah).* In the absence of evidence to the contrary, why assume that
the world is older than we are? But we now know that our entire writ-
ten history is just a one-sixteenth note in a long cosmic symphony of
many movements.
Try to stretch your mind around the sweep of time envisioned in this
new tale: ten thousand times a thousand times a thousand years. Just as
the Copernican revolution and its aftermath put us in our place in
space, teaching us that we are very small and not centrally located,
Cosmic Evolution shows our time to be tiny. Humans have been
around for perhaps a few million years, a hundredth of a percent of all
existence, so far. Next to nothing.
Feeling diminished? Not to worry. This story invites us to identify
&nb
sp; with something much larger: our biosphere—the totality of life on
Earth. “We,” Earth’s biosphere, have been around for a thousand times
longer, for several billion years. This is a significant fraction of cosmic
history, perhaps a third of it. So we are not so small, in time.
In one sense, this tale cannot compete with the older origin stories
because there are no people in it. Most chapters have no characters at
all, just particles and forces following blind compulsions of physical
law, and from this perspective it’s only the story of an elaborate
machine. Not that exciting, really. But through all its stages, the uni-
verse has been molting, preparing to awaken, becoming us and every-
thing else.
The presence of human minds, then, permeates this story, along with
the minds of any counterparts who may be watching the same drama
unfold from distant stellar perches. We’ve been in it all along. Cosmic
Evolution is not “merely” science. Longing to know our origins is a
spiritual itch that this story can help us scratch.
W H A T ’ S T H E S T O R Y ?
The word evolution in a scientific context usually conjures up the
procession of life-forms parading across Earth’s deep timescape. You
know: amoebas, algae, trilobites, apes, rock ’n’ roll drummers, humans
*A notable exception is Hindu cosmology, which describes a universe much older even than that described by Cosmic Evolution.
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and dolphins. But this chain of events on Earth is embedded with-
in a much larger sequence of transformations that first prepared the
ground and planted the seeds for local biological evolution. Cosmic
Evolution follows the universe through its own progression of forms. We
can trace a train of causality in which, following physical law, each devel-
opmental stage of the universe creates the conditions leading inevitably to
the next.
In every life there are pivotal moments: your first step, first words,
first kiss, the birth of a child, the death of a loved one. In human his-
tory there have been similar moments that have left us permanently
changed: starting to walk upright, the invention of agriculture, the
printing press, the electric guitar, humans walking on the Moon. The
universe, too, has passed through critical experiences that divide its his-
tory into distinct phases. Here I’ll briefly sketch out the major evolu-
tionary transitions that the universe, that we, have passed through. It’s
a story with chapters we know, even if the verses have not all been
worked out.
As the good witch said, it’s always best to start at the beginning. At
first, we were very small. And hot, too. According to a literal interpre-
tation of big-bang genesis, at the very beginning the entire universe was
all piled on top of itself in a single point of zero size with no surround-
ings—a point of infinite density and infinite temperature from which
sprang forth all matter and energy.*
In that ultradense primitive universe, there were no atoms, no struc-
tures of any kind. It was just too hot. Forming atoms or molecules in
such an environment would be as hopeless as trying to execute an elab-
orate tango in a mosh pit full of aggressive slam dancers. Try as they
might to hold together and execute their steps, the tango dancers would
instantly be pulled apart, merging with the joyously colliding crowd. In
the beginning, this was the only dance in town. It was way too hot to
tango.
But not for long. Soon, things had chilled enough for matter to make
something of itself. After about .00001 seconds the first simple struc-
tures formed. The temperature had dropped to 10 trillion degrees, just
*That’s the “standard theory.” A more recent variant of this holds that it was never zero size and infinite in density and temperature. Rather, according to “superstring cosmology”
the universe started out as a little nugget .000000000000000000000000000000000001
meters across with a temperature of 100,000,000,000,000,000,000,000,000,000,000
degrees. The beginning still needs work.
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cool enough for protons and neutrons to assemble out of the initial hot
soup of quarks. Thus began a long series of ever more intricate partner
dances, the latest of which is, at least around these parts, complex,
communicating sentient life.
A gradual increase in complexity over time is one of the major
themes tying together the tale of Cosmic Evolution. Matter is able to
assemble itself into more and more elaborate forms as the universe
expands and cools off. As the general heat-induced jostling subsides,
the self-attracting forces of matter are better able to resist the tumult,
and ever larger and more delicate creations materialize.
After a few seconds, when the universe had cooled to about 1 billion
degrees, protons and neutrons were able, by the attraction of atomic
forces, to gather themselves into hydrogen and helium—the first atoms.
Except, they were not complete atoms yet because the electrons were
running wild. In that heat, no nucleus could hold them, so the entire
universe was plasma—which we see today in a glowing star or a flash
of lightning.
Plasma ruled the universe for ages. Fast forward another three hun-
dred thousand years, when things had cooled down to a few thousand
degrees. This slowed the electrons down just enough so the nuclei could
reach out and hold them against the thermal storm. Atoms at last! The
plasma gave way to a hot gas of hydrogen and helium. This was a sig-
nificant moment in our cosmic history. Light cannot travel through a
thicket of free electrons, but now the universe as a whole suddenly
became transparent.
And there was light. The universe was white-hot. As it continued to
grow and cool, the ubiquitous rays of light expanded along with it, and
their wavelengths stretched out to ever redder and cooler colors. Over
billions of years, this background radiation has marched down the
spectrum from the visible range through infrared, then radio, down to
cold rays of microwave. The “cosmic microwave background” we see
coming from all directions today is the chilled-out, stretched-out after-
glow of that moment, only three hundred thousand years into Cosmic
Evolution, when light was set free by the formation of atoms.
Even as the microscopic structure of matter was slowly evolving
from chaos, climbing a ladder that had passed through quarks, protons
and neutrons, and simple atoms, the structure of the cosmos at the very
largest scales was also evolving. The universe was getting ready to build
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galaxies, the environments in which the rise of matter could continue,
where at
oms could achieve the next great leaps of complexity.
Although, as we have seen, in the earliest state of the universe no sta-
ble constructions of any kind could form, all was not completely uni-
form. From the beginning, random ripples pulsed in the formless fire-
ball of the primeval universe. In the rapid expansion that ensued, these
infinitesimal clumps were frozen into the structure of the universe and
they grew along with it. Eventually they became giant clouds and ten-
drils of gas millions of light-years across.
Then gravity took over. Establishing another theme that we will see
repeated, gravity tends to accentuate large-scale differences in density. It’s
the anti–Robin Hood of the universe, increasing disparities in the distri-
bution of mass, stealing from the poor and giving to the rich. Any clump
of matter has self-gravity. In the absence of other forces, a gas cloud will
contract, falling in on itself and becoming more dense, robbing matter
from its less dense surroundings. Gravitational contraction amplified the
primordial density differences, and these condensing clouds of gas became
the spiraling galaxies. Thus the tiniest things imaginable, little bumps
smaller than anything we can even detect with instruments, grew to
become galaxies—the sprawling, spinning arenas where generations of
stars are born, live, and die. On the face of it, this is harder to swallow
than any biblical, magical, or mythical tale. However, the evidence is com-
pelling. Our Milky Way and all the other whirling galaxies, the orbiting
clusters of dozens of galaxies and the vast superclusters containing thou-
sands of these—the largest structures in the universe—all started as infin-
itesimal random fluctuations when we were very small.
Galaxies formed fast. Since light moves at a finite speed, telescopes
are also time machines. With the Hubble Space Telescope, we can see
young galaxies already formed some 12 billion years ago.
As far as we can tell, the universe is only 13 or 14 billion years old.
There is some slop in these numbers, and they will continue to change
as the theorists and observers wrestle on into the twenty-first century.
But right now, it looks as if the galaxies are nearly as old as the universe
itself.
Unlike stars, which are still being born all the time, the galaxies are
all the same age, and still in their first and only generation. Though