Professor Ted
Bunn, a physics professor at the University of Richmond, recently came to Boston to speak
to us about the latest thinking on the nature of the physical universe and related
questions. The program took place in Emmanuel Church in Boston, and since we
needed to exercise our brains, as all the health latest advisories say we should --
though why this entails playing brain-exercise games on the Internet I'm not
sure I understand -- we trotted like good seekers of knowledge down to the
church on Sunday, arriving just as the church's coffee hour was
turning into the science presentation.
Professor
Ted did a great job of pointing out that most of the universe, according to the
latest scientific thinking, consists of either dark matter, or dark
energy. About 96 percent in total. That leaves 4 percent for the plain old ordinary
matter and energy, or as he put it, "atoms." So only 4 percent of
everything there is consists of anything we can know anything about; and the
names given to the other components, "dark" matter and "dark"
energy are not encouraging to the idea that we will come to "know"
these ingredients any time soon. We are very much "left in the dark"
about the contents of the universe.
Why is this
96 to 4 percent ratio not entirely comforting? What else are we potentially
missing out there? That's a
lot of weight in the "unknown" or even "unknowable" category
when you try to address one of the deepest of the traditional cosmological questions: What is the nature
of the universe?
So currently, it seems to me, if you wish
to go on believing that regiments of angels can dance on the head of a pin, or
that a near infinity of "multiverse" universes are dwelling unseen
among us, there is plenty of space in our largely
"dark" universe to carry on that order of speculation.
The 28
percent, or so, that is currently billed to the dark matter column is necessitated by
astrophysicists to account for the gravitational effect required by
the current theories to explain why the universe is not pulling apart any
faster than it is.
For, yes,
everything in the "universe" -- a term I take here to mean everything we know by our senses to
exist or have observed by some instrument -- is moving away
from everything else in the universe, according to the now widely accepted expanding
universe theory. This is possible because...
well, this is what our instruments and our equations are telling us.
And the question raised in my mind by this current scientific
tenet is: what is this universe expanding into?
Second
question (or observation): How lonely is that?
An
expanding universe raises the common sense consideration, not discussed in the
professor's talk, of how all those other sentient races out there with their presumably advanced
civilizations are going to contact us? Distance is a barrier to
travel; even to communication in the Einsteinian universe where the speed of
light is a constant. Fact is, so the current thinking tells us, we're just
getting farther apart.
From some
"imaginative" points of view of course, distance doesn't matter. But we call
those points of view "science fiction."
Worse, our
expanding universe would be running away from itself at a much faster rate if
something -- the professor called it "dark matter" -- did not exist to add its
"mass" to what we can observe in the universe (call it "atoms") to provide the
gravitational brake on universal expansion. That is to say, dark matter is a
hypothesis.
But why do
rely so much on "gravity," this child of the Newtonian universe whose
other lineaments we have left behind so long ago, to hold our picture of the
universe together? Is there something else out there -- some principal, or
force, or law -- we just don't know about yet?
Doesn't it
make as much sense to believe that the universe is riding on the back of an
enormous tortoise? Maybe we just haven't figured out how to "see" the
tortoise.
I am sorry
to confess that I make even less sense out of "dark energy," that
indefinable something current scientific thinking posits to fill some 68 percent of the
universe. Dark means we can't observe it; our instruments can't. So it's a
hypothesis.
So, the Wik
tells us that "in physical cosmology" dark energy is a hypothetical form
of energy that permeates all of space and accelerates the expansion of the
universe. That's "dark," all right. By comparison, dark energy turns that
archvillain The Lord of the Rings into a jumped-up schoolyard bully. Despite
its domination of the universe, the theory goes, it's not much of a force within our
own solar system, weighing a mere 6 tones in total, about the size of one our
neighborhood SUVs. However, according to current thinking, dark energy dominates
"the mass-energy" of the universe because it spreads uniformly
throughout space. Remember, there is a lot more "space" than there
are solar systems.
The
universe is, measurably, expanding, this reasoning goes. Some force must drive it; must overpower
the universal gravity that holds us together. Since we know nothing about this
force, except there must be a lot of it, we create another hypothesis: "dark energy."
And so,
since this picture of the universe gives me almost nothing with which to
address the basic cosmological questions:
What is the
nature of the universe? (or "the world"? or "life"?)
How did the
universe begin? If it began in "time," what was there before the
universe?
Is the
universe finite? Infinite? If it is finite, what exists outside the universe? If
it is "expanding," what is it expanding into?
And why is
there being rather than nothingness? Or,
in another common formulation, why do we exist? ...
.... I
turn, as I have done before, to the poem by Walt Whitman that best sums up
for me the difference between what science can deliver to benefit the always
restless human mind and what the human soul requires:
When
I heard the learn’d astronomer
When I heard the learn’d
astronomer,
When the proofs, the figures,
were ranged in columns before me,
When I was shown the charts and
diagrams, to add, divide, and measure them,
When I sitting heard the
astronomer where he lectured with much applause in the lecture-room,
How soon unaccountable I became
tired and sick,
Till rising and gliding out I
wander’d off by myself,
In the mystical moist night-air,
and from time to time,
Look’d up in perfect silence at
the stars.
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