From the door came a scratching sound. MacPherson turned to see Joe,
grinning at them through the steel lattice.
"How's things?" Joe wanted to know. "Thought I heard a commotion in
here. Doc Rothman's not acting up, I hope?"
"Everything's under control, Joe," MacPherson assured him. "Just having
a friendly game."
"Don't cheat while they're watching you," said Joe, and his face
disappeared.
"Well, the murder's out," said MacPherson.
"No use kidding you any longer," Neill said, fanning his cards.
"Eleven o'clock this morning. Six o'clock tomorrow morning, Waaku time.
But it's just another test. Nothing's going to happen."
Avery took off his glasses and began to polish the lenses. "Any idea
of a possible chain reaction is ridiculous. As a matter of fact, I
recently spent a full week checking the math again myself, so I know.
But we knew how you felt about it, Rothman, and we didn't want you to
be worrying here all alone, in case you'd found out. That's why we
came."
Rothman was looking out the window. He did not answer. Slowly
MacPherson went back to his chair and picked up his cards. "And now how
about playing some poker? Rothman, you opened for a blue. What about
you, Neill?"
"I'm staying," said Neill, shoving in a chip. "Always was a gambler.
I'm going to stay till the cows come home."
"What time is it?" Rothman asked. "I haven't got a wristwatch. They
think I might break the crystal and cut my throat."
MacPherson slammed down his cards and jerked his watch from his pocket.
"What does it matter what time it is? Why couldn't they give you a
watch with a plastic crystal? If you have to know, it's eleven-forty."
"And thirteen seconds," added Neill.
"Then it's already started," said Rothman.
* * * * *
He leaned his head against the back of his chair and closed his eyes.
"It's on its way now. There's somewhat more than a third of the
Earth between us and Waaku--the place where Waaku was, I mean. The
disintegration wave is moving slowly. The seismic wave of an earthquake
would get here in about fifty minutes, more or less. But the shock wave
from Waaku, traveling somewhere around five thousand miles an hour,
will need about an hour and seventeen minutes, plus or minus a minute
or so. That means it will reach us in about thirty-seven minutes from
now, and the disintegration wave is following close behind. Well, nice
to have known you, fellows. Anyone want to check my math?"
He waved toward the desk behind him, piled high with manuscript and a
sprawling heap of books on which rested a slide-rule.
"Calm down," said MacPherson. "Nothing is going to happen. Damn you,
Avery! Are you proud of what you accomplished?"
Avery glared. "It'll do him good! He's got to learn to face reality,
like the rest of us. In a little more than half an hour, the test will
be finished. The world will still be here. Rothman will have to admit
his equations were wrong--and then he'll be cured."
Rothman leaned forward. "Or contrariwise, Rothman will _not_ have to
admit he was wrong and Rothman will _not_ be cured! If I made a mistake
in my math, why couldn't anybody put his finger on it? I'm not so crazy
that I wouldn't be able to see an error in calculus when it was pointed
out to me. If you're sure my calculations are wrong, why do you look so
frightened?"
"Do we have to go over all that again?" said MacPherson. "The boys
at Columbia told you where the mistake was. It's where you inverted
that twelve-by-twelve matrix. Didn't you bother to check the inverted
matrix?"
"The same old tale." Rothman picked up his cards. "No mathematician
will ever admit that another mathematician could invent a method beyond
his comprehension. Still harping on an error in my inverted matrix.
What time is it now?"
"There's no doubt that your calculations are wrong," said Neill, "but
I still don't see why we have to insist on proving it the hard way.
With bombs, why do we need to fool around with the total disintegration
of matter? Sure, I know the new model releases a googol times the
energy you get out of uranium fission, but who cares? There's plenty of
uranium for our needs."
"The trouble with uranium is that it doesn't make a big enough bang,"
said MacPherson. "People aren't impressed by it any more. The same
goes for plutonium, even for lithium, at least for any size bomb we
can make. The idea is to show the world something so convincing that
they'll never even think of a war again. When they see every island in
the Waaku chain wiped off the map, they'll get the point."
* * * * *
Avery creased another card and cleared his throat. "_Did_ you check the
inverted twelve-by-twelve, Rothman?"
"I suppose you think I forgot to. Have _you_ checked it?"
"Yes, I have. I may not know much math, but I did check it."
"Even after the Columbia boys said it was nonsense? Well, does it come
out right?"
"No, it doesn't! You multiply the inverted matrix by the original and
you not only don't get zeros for all elements outside the diagonal,
you get a haphazard assortment of ones and twos. Worse still, every
element in the diagonal comes out equal to zero. The product of the two
matrices is about as different from the identity matrix as anything
could be. You're one of our most brilliant mathematicians--how could
you manage to make so many mistakes in one set of calculations?"
"Did I tell you that was an inverted matrix? Maybe, for this problem,
you need something a little more advanced than algebra. Anyhow, if my
math is all wrong, why did your first report okay it?"
"What do you mean, my first report?"
"The one you sent to Prexy. The one you later called in and burned.
Except Prexy showed it to me and I photostated it. Here." Rothman
reached into the pile of papers on his desk and drew out a little
envelope. It contained photographic prints. He held one before Avery's
glasses. "Does that look familiar?"
Avery drew his hand across his forehead, but did not reply.
"Is that true, Avery?" asked MacPherson. "Did you make a report okaying
Rothman's calculations and then withdraw it?"
"Well, what if I did? The report didn't seem to make me much more
popular than Rothman was. What if some very influential people in
Government explained to Prexy, and he explained to me, just how
unpopular that first report might make me? Or suppose they didn't.
Maybe I simply didn't find the mistakes in the math until later." Avery
kept looking at his cards as he spoke.
"Oh, great," said MacPherson. "Rothman gets put away here, Neill and
I lose our jobs, and there's hell to pay in Washington, all because
Avery says Rothman's math is full of holes. Now it turns out he wasn't
sure and maybe was pressured into it. Grand. Between a screwball and a
skunk, I'll choose the screwball. Maybe if Avery had stuck to his guns,
there wouldn't have been any test."
* * * * *
"It doesn't matter," said Rothman. "Avery was probably warned to mend
his ways. I was. Or maybe he couldn't face the truth. I'm sure he's
been much happier, the last few months, believing I'm crazy. Anyway,
I don't blame him any more. Maybe my math will soon speak for itself.
For your benefit--" he turned to Avery--"I may point out that the
errors you said you found affect only the _velocity_ of the wave of
disintegration. So what if that isn't quite right? The proof that the
reaction will be self-sustaining is independent of that."
Avery was white with rage. "The proof, as you called it, that the
reaction will be self-sustaining and will consume the entire substance
of the Earth doesn't make sense, either. You used D as an operator
where it should have been a constant. That's what finally made them
certain that you were insane."
There was a rap at the door and Joe poked his head in. "Lunch,
Professors! Twelve o'clock, high noon, like they say. How about some
turkey sandwiches?"
MacPherson began to sweat; the thought of food made him feel sick.
Was it possible, he wondered, that in spite of everything, he was not
quite sure? He looked at Neill and Avery, but they had turned their
heads away.
"We won't bother with lunch, Joe," said Rothman.
"Must be a pretty good game if you won't even knock off to eat," said
Joe. "Well, will you at least mark your menu for tomorrow?"
"For tomorrow? Tomorrow isn't going to come, you know."
"Nuts," muttered Joe as he closed and locked the door. "Pure nuts."
Avery cleared his throat, and his voice was thin. "Look here, Rothman!
If the Universe were composed of matter as unstable as you claim,
it would have ceased to exist long ago. Somewhere, somehow, in the
infinity of chance events since the creation of the Earth, something
would have occurred to start the self-sustaining chain reaction, and
all matter would have been annihilated."
"Are you trying to prove something to yourself?" asked Rothman. "Surely
you don't equate infinity with a mere four billion years. That's
a finite time--long enough for the more dangerous radioactives to
disappear completely, of course, but not long enough for all possible
chance events to have taken place. Anyway, I never have asserted that
the reaction would reach from Earth to the other planets, or even to
the Moon. The Universe, including the Solar System, will still go on.
But our old Earth is going up like a pile of magnesium powder mixed
with potassium chlorate when you drop a lighted match on it."
* * * * *
Avery wiped his forehead. "I don't know why I keep arguing with
a lunatic. But you know yourself that the value you give for the
integration constant in those equations is a pure guess, only you
spend ten pages of doubletalk trying to hide that fact. If the constant
is the one you give, why, sure, then you get a chain reaction. But
you made it up! Who ever heard of a constant of that magnitude in the
solution of an ordinary differential equation?"
"That's one criticism of my work the Harvard and Columbia boys never
mentioned."
"Okay, then I mention it. You're crazy!"
"Are you sure?"
"Positive!"
"Then why can't you forget the approach of zero hour? I'll tell you
why and you aren't even making a good show of hiding it. You know
that, compared to mine, your knowledge of mathematics is about on a
level with that of a college sophomore. Deep down, you know that my
calculations were correct. You are convinced--_convinced_--that the
bombing of Waaku has already started a chain reaction. And that about
seventeen minutes past twelve, around eight minutes from now, the shock
wave will reach us, and then the wave of disintegration. Look out of
the window! See that cactus in the sand, with its little yellow flower?
It will be annihilated. All that desert will go, too--every pebble,
every grain of sand. Everything you see, and you yourself, will be
disintegrated, transformed into energy!"
Suddenly he relaxed into a grin and softened his voice. "I thought we
were playing poker. We're waiting for you to bet. Why don't you at
least look at your cards?"
Avery opened his mouth, then closed it, and picked up his hand,
riffling the five cards.
"I'm staying," he said. "Here's your blue and I raise you a blue."
Slowly the others picked up their hands and stared at the cards.
MacPherson scarcely looked at his as he spoke.
"I'm staying." He picked up the deck. "Cards, gentlemen?"