A Step Farther Out (22 page)

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Authors: Jerry Pournelle

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BOOK: A Step Farther Out
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It was only partly filled: graduate students, several undergraduates, a sprinkling of faculty, one or two of the top names in theoretical physics. It was a room of serious women and men, mostly younger than I, all expectantly quiet. At the bottom of the well, the focus of attention on the stage, was
an incredibly thin, very young-appearing man seated in a high-backed motorized chair of Victorian design; the chair had no flavor of the hospital about it. He wore a light suit, dark shirt, and flowered tie, and he kept his hands folded carefully in his lap as he was introduced.

The chairman gave his credits and spoke wonderingly of how privileged we were to hear a man of this stature. No one disagreed. Not, of course, that anyone would have said anything no matter what he thought, but the total silence in the room was an obvious sign of unanimous assent.

Hawking began to speak Everyone leaned slightly forward, straining to hear. Except for the heavily slurred voice there was absolutely no sound; you could quite literally hear a pen drop, for I dropped mine and it clattered loudly on the cement floor.

This is the scene, then: a lecture room partly filled with very bright people, a few extremely well known in theoretical physics, others students at one of the world's most prestigious institutions. They all strain to hear a wizened young man who makes awkward gestures and speaks with a thick slur that keeps his words just at the edge of intelligibility.

He grins like a thief. He's obviously not in pain, and he doesn't feel sorry for himself. And he tells that room of bright people that everything they thought they knew is nonsense. And he chuckles.

He tells us that the pudding that ate Chicago may someday exist; that duplicates of each one of us may one day wander the universe; that
anything can,
and probably will, happen. He tells us that the universe isn't lawful, never will be lawful, never
can
be lawful; that we
cannot ever
know enough to predict the totality of events in this universe; that at best we study local phenomena that may be predictable for an unspecifiable time.

And he laughs.

He tells us that Cthulthu may exist after all.

As I said, it was an afternoon of Lovecraftian horror.

Larry and I escaped with our sanity, after first, in the question period, making certain that Hawking really did say what we thought he'd said.

He had.

* * *

Stephen Hawking's lecture had originally been entitled "The Breakdown of Physics in the Region of Space-Time Singularities." The title was flashed on the screen; then another slide took its place, and Hawking chuckled. The new slide said:

THE BREAKDOWN OF
PHYSICS
PHYSICISTS
IN THE REGION OF SPACE-TIME SINGULARITIES

He began simply enough. The principle of equivalence, he said, is well established. This is the principle that states that
inertial
mass, that is, the resistance of objects to being moved by an outside force, is exactly equivalent to
gravitational
mass, that is, the gravitational force a given mass will exert. There are not two kinds of mass.

This was Galileo's principle, and there's the famous apocryphal story of his dropping a cannon-ball and a musket-ball from the Leaning Tower of Pisa and observing their striking the ground at the same time. Obviously if gravitational and inertial mass were different, heavy objects would
not
fall at the same speed as light ones.

So far so good. Next, gravity affects light. It can bend light rays, as predicted by Einstein and observed several times in solar eclipses.

Now in short order: the energy-momentum tensor of gravity is positive; gravity is universally attractive, not repellent. Therefore, enough mass will create a field from which no light can escape.

The Special Theory of Relativity says that nothing can travel faster than light.

And
therefore
sufficient mass must create a space-time singularity, a place which cannot be observed.

A singularity is therefore inevitable; that is, at least one singularity must exist, provided only. (1) that Einstein's general relativity is correct; (2) gravity is truly attractive and never repellent; and (3) enough mass has ever been collected together.

And
therefore
at least one singularity exists in our universe, since at the time of the Big Bang all the conditions certainly prevailed; and also, it's very likely that other singularities have been created by collapse of stars, since many stars have more than enough matter and don't have enough energy to throw that matter away as they die.

* * *

OKAY so far? Nothing startling here. Bit dry, but all we've shown is that singularities must exist, and nearly everyone accepts the idea now. They're hidden away inside black holes, of course, and observers are now very nearly certain that we can
observe
a
black hole.

Well, not observe the hole itself; but Cygnus X-l, an x-ray emitting star in the constellation Cygnus, has an invisible companion and the pair of stars, the one we can see and the one we can't, together act very like what Gal Tech's Kip Thorne predicted such a pair would act like if one were a black hole.

So what else is new? We've proved black holes can exist, and lo, the observers think they've found one. What's scary about
that?

Nothing, so far. Holes aren't scary unless you're about to fall into one. We even understand them. We know they "have no hair," that is, that they can be completely described given their mass, M; angular momentum, J; and electric charge, Q, Given these data we can describe their shape, and predict what effect they'll have on nearby objects, and play all kinds of fascinating scientific-theory games.

We can talk about black hole bombs, and toy with ideas on how to extract energy
from
them: take one rotating black hole, throw garbage into it, and you not only get rid of the garbage, but can get useful energy back out. There are speculations (not SF; just plain science) about extremely advanced civilizations using black holes for precisely that purpose.

There's just no end to the nice things you could do with black holes, and although not many years ago they were no more than toys for theoreticians to play mental games with, black holes have become household-word objects now.

Black holes don't make us nervous.

Ah, but inside each black hole there lurks a singularity. This is the little beastie that breaks down physics in the nearby regions. By definition they do things we can't predict. They behave in strange ways. Up close to them time reversals can happen. How, then, can we avoid this breakdown of our nice predictable universe?

Hawking discussed several theoretical alternatives, and dismissed each. A couple of the cases seemed to startle one of the big-name theoreticians listening to the lecture. When Hawking was finished, though, the singularities were back and inevitable. I won't pretend to have understood all of this part of the lecture; and I wouldn't bore my readers with it if I had. If you appreciate that sort of thing you'll read Hawking's paper when it comes out.

For the rest of us I sum up by saying that he found no good alternatives; eliminating General Relativity doesn't eliminate the singularities, or else lands you in an even worse theoretical soup.

Therefore, let us look at General Relativity; but let us add quantum theory to it. Hawking recently published that work, and I described it here.

The important fact is that the quantum effects violate cosmic censorship. The Law of Cosmic Censorship, you may recall, states that there shall be no naked singularities; every singularity shall be decently clothed with an event horizon that prevents us from ever being able to observe it directly, and thus prevents us from observing the region in which physics breaks down.

Thus we needn't fear the singularity. It can't affect our lives, because nothing it does can get out of that black hole "around" it.

But adding quantum effects to General Relativity repeals cosmic censorship. Black holes evaporate. Big ones slowly, small ones rapidly, all inevitably. And what of the singularity that MUST have been created by the Big Bang of creation?

Evaporation of black holes produces naked singularities. We may play about with the concept of quantizing relativity, and Hawking did; but the conclusion was inescapable. Again I don't pretend to have followed every step, nor did most of the rest of us in that room; but several did, and they weren't pleased.

Because now comes the punchline. The singularities emit matter and energy. And "they emit all possible configurations with equal probability. Thus, perhaps, this is why the early universe from the Big Bang singularity was in thermal equilibrium and was very nearly homogeneous and isotropic. Thermal equilibrium would represent the largest number of configurations."

But since that time the universe has changed, and we have stars and planets and nematodes and comets and people; but the singularity must still be around. It emits. And what comes out is completely random, absolutely un-correlated. This fundamental breakdown in prediction—Hawking is saying not only that we can't predict
now,
but that in principle we can
never
predict, no matter how much we know or how smart we get or how large a computer we build—is a "consequence of the fact that General Relativity allows fundamental changes in the topology of space-time; that is, allows holes.

"Matter and information can fall into these holes—or can come out. And what comes out is completely random and uncorrelated."

The hole can emit anything. Anything at all.

* * *

"No," I thought. I looked to Niven. "No," he was thinking. Surely we misunderstood.

And the thin chap grinned ever more broadly. "Of course we might have to wait quite a while for it to emit one of the people here this afternoon, or myself, but eventually it must—"

Hawking chuckled and waited expectantly, and after a long and very silent pause first one, then another joined him in laughter; but it had a rather hollow sound, or so I thought. Larry agreed when we could talk about it later.

So far as we can tell, we've just heard one of the top people in theoretical physics tell us that we don't know anything and can't know anything; that causality is a local phenomenon of purely temporary nature; that time travel is possible; that Cthulthu might emerge from a singularity, and indeed is as probable as, say, H. P. Lovecraft.

Hawking concluded by reminding us that Albert Einstein once said "God does not play dice with the universe."

"On the contrary," Hawking said, "it appears that not only does God play dice, but also that he sometimes throws the dice where they cannot be seen!"

* * *

Lovecraftian horror indeed. Our rational universe is crumbling. Western civilization assumes reason; that some things are
impossible, that's all,
and we can know that; that werewolves don't exist, and there never was, never could be, a god Poseidon, or an Oracle that spoke truly; that the universe is at least in principle discoverable by human reason, is
knowable.

That, says one of the men we believe best understands this universe, is not true. It's not very probable that Cthulthu will emerge from the primeval singularity created in the Big Bang, or that Poseidon will suddenly appear on Mount Olympus, but neither is
impossible;
and for that matter, this world we think we understand, which seems to obey rational laws we can discover, isn't very probable either—isn't, in fact, in the long run any more probable than a world that includes Cthulthu, or the pudding that ate Chicago.

* * *

Well, of course I don't believe that; not in the sense that I'm going to alter my life to conform to a lawless and unpredictable universe. But I am now reduced to an act of faith: an irrational belief that the world and universe are, must be, lawful, and rational.

This is not "faith in science" or believing in science; not any more. It never was, actually; but Hawking has laid bare the hidden flaw. So long as science itself concluded that the universe was lawful, few of us were tempted to ask
why
this should be so, or to realize that this is the one question science can never answer.

Now, though, science itself says the universe is not lawful. If you
"want a
lawful universe, you've got to take a leap of faith; you've got to hold fast to an irrational belief While you're doing that, why not also believe there's a higher purpose to it all?

Is it harder to believe the universe is lawful and purposeful than to believe it is lawful but without purpose?

* * *

In the Beginning, the Big Bang emitted Chaos; and the Chaos was without form, and void, for it was homogeneous and isotropic. And the Singularity moved upon the face of the Chaos and emitted light; and the Universe was no longer homogeneous, for the light was divided from the darkness.

And there came forth firmaments and dry land and seas and stars and moons; and the worlds brought forth grass, the herb yielding seed, and the fruit trees yielding fruit after his kind, whose seed is in itself.

It is quite literally true that if you can believe that, you can believe anything; more, you
must
believe anything. To exclude anything you must make an act of faith.

* * *

As we drove away from Pasadena, Larry remarked that if we ever had proximity to a singularity, he could well imagine people praying to it. After all, their prayers probably wouldn't influence what came out of it—but they might, and certainly nothing else would. I even had an idea for a flippant story to be entitled "The Oracle."

I don't think I'll write that story.

If this new work of Hawking's holds up—and if we've correctly interpreted what we heard—there are going to be some changes in the fundamentals of Western Civilization.

Will philosophy once again become the "Queen of Sciences"? I don't know; I suspect, though, that what we heard during our Lovecraftian afternoon will have a long reach. We either need some fundamental new breakthroughs in theoretical physics—and I've heard no hint of what they may be—or we'll have to start thinking about faith again.

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