ASTRONAUTS thrill to photograph the earth as
it looms large through the window of a spacecraft. “That’s the best part of
flying in space,” said one. But our earth seems very small when compared with
the solar system. The sun could hold a million earths inside, with room to
spare! However, could such facts about the universe have any bearing on your
life and its meaning?
Let us take a brief mental trip into space to
see our earth and sun in perspective. Our sun is just one of an awesome number
of stars in a spiral arm of the Milky Way galaxy, which itself is just a tiny
part of the universe. With the naked eye, it is possible to see a few smudges
of light that actually are other galaxies, such as the beautiful and larger
Andromeda. The Milky Way, Andromeda, and some 20 other galaxies are bound
gravitationally into a cluster, all of these being only a small neighborhood in
a vast supercluster. The universe contains countless superclusters, and the
picture does not end there.
The clusters are not evenly distributed in
space. On a grand scale, they look like thin sheets and filaments around vast
bubblelike voids. Some features are so long and wide that they resemble great
walls. This may surprise many who think that our universe created itself in a
chance cosmic explosion. “The more clearly we can see the universe in all its
glorious detail,” concludes a senior writer for Scientific American,
“the more difficult it will be for us to explain with a simple theory how it
came to be that way.”
Evidence Pointing to
a Beginning
All the individual stars you see are in the
Milky Way galaxy. Until the 1920’s, that seemed to be the only galaxy. You
probably know, though, that observations with larger telescopes have since
proved otherwise. Our universe contains at least 50,000,000,000 galaxies. We do
not mean 50 billion stars—but at least 50 billion galaxies, each
with billions of stars like our sun. Yet it was not the staggering quantity of
huge galaxies that shook scientific beliefs in the 1920’s. It was that they are
all in motion.
Astronomers discovered a remarkable fact:
When galactic light was passed through a prism, the light waves were seen to be
stretched, indicating motion away from us at great speed. The more distant a
galaxy, the faster it appeared to be receding. That points to an expanding
universe!
Even if we are neither professional
astronomers nor amateurs, we can see that an expanding universe would have
profound implications about our past—and perhaps our personal future too.
Something must have started the process—a force powerful enough to overcome the
immense gravity of the entire universe. You have good reason to ask, ‘What
could be the source of such dynamic energy?’
Although most scientists trace the universe
back to a very small, dense beginning (a singularity), we cannot avoid this key
issue: “If at some point in the past, the Universe was once close to a
singular state of infinitely small size and infinite density, we have to ask
what was there before and what was outside the Universe. . . . We
have to face the problem of a Beginning.”—Sir Bernard Lovell.
This implies more than just a source of vast
energy. Foresight and intelligence are also needed because the rate of
expansion seems very finely tuned. “If the Universe had expanded one million
millionth part faster,” said Lovell, “then all the material in the Universe
would have dispersed by now. . . . And if it had been a million
millionth part slower, then gravitational forces would have caused the Universe
to collapse within the first thousand million years or so of its existence.
Again, there would have been no long-lived stars and no life.”
Attempts to Explain
the Beginning
Can experts now explain the origin of the
universe? Many scientists, uncomfortable with the idea that the universe was
created by a higher intelligence, speculate that by some mechanism it created
itself out of nothing. Does that sound reasonable to you? Such speculations
usually involve some variation of a theory (inflationary universe model)
conceived in 1979 by physicist Alan Guth. Yet, more recently, Dr. Guth
admitted that his theory “does not explain how the universe arose from nothing.”
Dr. Andrei Linde was more explicit in a Scientific American
article: “Explaining this initial singularity—where and when it all began—still
remains the most intractable problem of modern cosmology.”
If experts cannot really explain either the
origin or the early development of our universe, should we not look elsewhere
for an explanation? Indeed, you have valid reasons to consider some evidence
that many have overlooked but that may give you real insight on this issue. The
evidence includes the precise measurements of four fundamental forces that are
responsible for all properties and changes affecting matter. At the mere
mention of fundamental forces, some may hesitate, thinking, ‘That’s solely for
physicists.’ Not so. The basic facts are worth considering because they affect
us.
Fine-Tuning
The four fundamental forces come into play
both in the vastness of the cosmos and in the infinite smallness of atomic
structures. Yes, everything we see around us is involved.
Elements vital for our life (particularly
carbon, oxygen, and iron) could not exist were it not for the fine-tuning of
the four forces evident in the universe. We already mentioned one force, gravity.
Another is the electromagnetic force. If it were significantly
weaker, electrons would not be held around the nucleus of an atom. ‘Would that
be serious?’ some might wonder. Yes, because atoms could not combine to form
molecules. Conversely, if this force were much stronger, electrons would be
trapped on the nucleus of an atom. There could be no chemical reactions between
atoms—meaning no life. Even from this standpoint, it is clear that our
existence and life depend on the fine-tuning of the electromagnetic force.
And consider the cosmic scale: A slight
difference in the electromagnetic force would affect the sun and thus alter the
light reaching the earth, making photosynthesis in plants difficult or
impossible. It could also rob water of its unique properties, which are vital
for life. So again, the precise tuning of the electromagnetic force determines
whether we live or not.
Equally vital is the intensity of the
electromagnetic force in relation to the other three. For example, some
physicists figure this force to be 10,000,-
000,000,000,000,000,000,000,000,000,000,000,000 (1040) times
that of gravity. It might seem a small change to that number to add one more
zero (1041). Yet that would mean that gravity is proportionally weaker,
and Dr. Reinhard Breuer comments on the resulting situation: “With lower
gravity the stars would be smaller, and the pressure of gravity in their
interiors would not drive the temperature high enough for nuclear fusion
reactions to get under way: the sun would be unable to shine.” You can imagine
what that would mean for us!
What if gravity were stronger
proportionately, so that the number had only 39 zeros (1039)? “With
just this tiny adjustment,” continues Breuer, “a star like the sun would find
its life expectancy sharply reduced.” And other scientists consider the
fine-tuning to be even more precise.
Indeed, two remarkable qualities of our sun
and other stars are long-term efficiency and stability. Consider a simple
illustration. We know that to run efficiently, an automobile engine needs a
critical ratio between fuel and air; engineers design complex mechanical and
computer systems to optimize performance. If that is so with a mere engine,
what of the efficiently “burning” stars such as our sun? The key forces
involved are precisely tuned, optimized for life. Did that precision just
happen? The ancient man Job was asked: “Did you proclaim the rules that govern
the heavens, or determine the laws of nature on earth?” (Job 38:33, The New
English Bible) No human did. So from where does the precision
come?
The Two Nuclear
Forces
The structure of the universe involves much
more than fine-tuning just gravity and the electromagnetic force. Two other
physical forces also relate to our life.
These two forces operate in the nucleus of an
atom, and they give ample evidence of forethought. Consider the strong nuclear
force, which glues protons and neutrons together in the nucleus of the
atom. Because of this bonding, various elements can form—light ones (such as
helium and oxygen) and heavy ones (such as gold and lead). It seems that if
this binding force were a mere 2-percent weaker, only hydrogen would exist.
Conversely, if this force were slightly stronger, only heavier elements, but no
hydrogen, could be found. Would our lives be affected? Well, if the universe
lacked hydrogen, our sun would not have the fuel it needs to radiate
life-giving energy. And, of course, we would have no water or food, since
hydrogen is an essential ingredient of both.
The fourth force in this discussion, called
the weak nuclear force, controls radioactive decay. It
also affects thermonuclear activity in our sun. ‘Is this force fine-tuned?’ you
might ask. Mathematician and physicist Freeman Dyson explains: “The weak
[force] is millions of times weaker than the nuclear force. It is just weak
enough so that the hydrogen in the sun burns at a slow and steady rate. If the
weak [force] were much stronger or much weaker, any forms of life dependent on
sunlike stars would again be in difficulties.” Yes, this precise rate of
burning keeps our earth warm—but not incinerated—and keeps us alive.
Furthermore, scientists believe that the weak
force plays a role in supernova explosions, which they give as the mechanism
for producing and distributing most elements. “If those nuclear forces were in
any way slightly different from the way they actually are, the stars would be
incapable of making the elements of which you and I are composed,” explains
physicist John Polkinghorne.
More could be said, but you likely understand
the point. There is an amazing degree of fine-tuning in these four fundamental
forces. “All around us, we seem to see evidence that nature got it just right,”
wrote Professor Paul Davies. Yes, the precise tuning of the fundamental forces
has made possible the existence and operation of our sun, our delightful planet
with its life-sustaining water, our atmosphere so vital for life, and a vast
array of precious chemical elements on earth. But ask yourself, ‘Why such
precise tuning, and from where?’
Earth’s Ideal Features
Our existence requires precision in other
respects as well. Consider the earth’s measurements and its position relative
to the rest of our solar system. The Bible book of Job contains these humbling
questions: “Where did you happen to be when I founded the earth? . . .
Who set its measurements, in case you know?” (Job 38:4, 5) As never
before, those questions beg for answers. Why? Because of the amazing things
that have been discovered about our earth—including its size and its position
in our solar system.
No planet like earth has been found elsewhere
in the universe. True, some scientists point to indirect evidence that certain
stars have orbiting them objects that are hundreds of times larger than the
earth. Our earth, though, is just the right size for our existence. In what
sense? If earth were slightly larger, its gravity would be stronger and
hydrogen, a light gas, would collect, being unable to escape the earth’s
gravity. Thus, the atmosphere would be inhospitable to life. On the other hand,
if our earth were slightly smaller, life-sustaining oxygen would escape and
surface water would evaporate. In either case, we could not live.
The earth is also at an ideal distance from
the sun, a factor vital for life to thrive. Astronomer John Barrow and
mathematician Frank Tipler studied “the ratio of the Earth’s radius and
distance from the Sun.” They concluded that human life would not exist “were
this ratio slightly different from what it is observed to be.” Professor David
L. Block notes: “Calculations show that had the earth been situated only 5 per
cent closer to the sun, a runaway greenhouse effect [overheating of the earth]
would have occurred about 4 000 million years ago. If, on the other hand, the
earth were placed only 1 per cent further from the sun, runaway glaciation
[huge sheets of ice covering much of the globe] would have occurred some 2 000
million years ago.”—Our Universe: Accident or Design?
To the above precision, you can add the fact
that the earth rotates on its axis once a day, the right speed to produce
moderate temperatures. Venus takes 243 days to rotate. Just think if the earth
took as long! We could not survive the extreme temperatures resulting from such
long days and nights.
Another vital detail is our earth’s path
around the sun. Comets have a wide elliptic path. Thankfully, this is not so
with the earth. Its orbit is almost circular. Again, this prevents us from
experiencing death-dealing extremes of temperature.
Nor should we ignore the location of our
solar system. Were it nearer the center of the Milky Way galaxy, the
gravitational effect of neighboring stars would distort the orbit of the earth.
In contrast, were it situated at the very edge of our galaxy, the night sky
would be all but devoid of stars. Starlight is not essential to life, but does
it not add great beauty to our night sky? And based on current concepts of the
universe, scientists have calculated that at the edges of the Milky Way, there
would not have been enough of the needed chemical elements to form a solar
system like ours.
Law and Order
From personal experience, you likely know
that all things tend toward disorder. As any homeowner has observed, when left
to themselves, things tend to break down or disintegrate. Scientists refer to
this tendency as “the second law of thermodynamics.” We can see this law at
work daily. If left alone, a new automobile or bicycle will become scrap.
Abandon a building and it will become a ruin. What about the universe? The law
applies there too. So you might think that the order throughout the universe
should give way to complete disorder.
However, this does not seem to be happening
to the universe, as Professor of Mathematics Roger Penrose discovered when he
studied the state of disorderliness (or, entropy) of the observable universe. A
logical way to interpret such findings is to conclude that the universe started
off in an ordered state and is still highly organized. Astrophysicist Alan
Lightman noted that scientists “find it mysterious that the universe was
created in such a highly ordered condition.” He added that “any successful
theory of cosmology should ultimately explain this entropy problem”—why the
universe has not become chaotic.
In fact, our existence is contrary to this
recognized law. So why is it that we are alive here on earth? As previously
noted, that is a basic question that we should want answered.
[Footnotes]
The Milky Way galaxy is some 600 quadrillion
miles [about a quintillion km] in diameter—yes,
600,000,000,000,000,000 miles [1,000,000,000,000,000,000 km]! It
takes light 100,000 years to cross it, and this one galaxy contains over
100 billion stars!
In 1995, scientists noticed the strange
behavior of the most distant star (SN 1995K) ever observed as it exploded in
its galaxy. Like supernovas in nearby galaxies, this star became very bright
and then slowly faded but over a longer period than ever before detected. New
Scientist magazine plotted this on a graph and explained: “The shape of
the light curve . . . is stretched in time by exactly the amount
expected if the galaxy was receding from us at nearly half the speed of light.”
The conclusion? This is “the best evidence yet that the Universe really is
expanding.”
The inflation theory speculates as to what
happened a fraction of a second after the beginning of the universe. Advocates
of inflation hold that the universe was initially submicroscopic and then
inflated faster than the speed of light, a claim that cannot be tested in a
laboratory. Inflation remains a debated theory.
For more informative articles please go to www.jw.org
