"Hear hear!"
"Quiet, you renegade Irishman. Besides that, you m-r's give us our first real chance to check another matter. Are you familiar with the relativity transformations?"
"You mean the Einstein equations?
"Surely. You know the one for time?"
I thought hard Pat and I had taken first-year physics our freshman year; it had been quite a while. I picked up a piece of paper and wrote down what I thought it was:
"That's it," agreed Dr. Babcock. "At a relative velocity of 'v' time interval at first frame of reference equals time interval at second frame of reference multiplied by the square root of one minus the square of the relative velocity divided by the square of the speed of light. That's just the special case, of course, for constant speeds; it is more complicated for acceleration. But there has been much disagreement as to what the time equations meant, or if they meant anything."
I blurted out, "Huh? But I thought the Einstein theory had been proved?" It suddenly occurred to me that, if the relativity equations were wrong, we were going to be away a mighty long time—Tau Ceti, our first stop, was eleven light-years from the Sun... and that was just our first one; the others were a lot farther.
But everybody said that once we got up near the speed of light the months would breeze past like days. The equations said so.
"Attend me. How do you prove that there are eggs in a bird's nest? Don't strain your gray matter: go climb the tree and find out There is no other way. Now we are climbing the tree."
"Fine!" said O'Toole. "Go climb a tree."
"Noisy in here. One school of thought maintained that the equations simply meant that a clock would read differently if you could read it from a passing star... which you can't... but that there was no real stretching or shrinking of time-whatever 'real' means. Another school pointed to the companion equations for length and mass, maintaining that the famous Michelson-Morley experiment showed that the length transformation was 'real' and pointing out that the increase of mass was regularly computed and used for particle-accelerator ballistics and elsewhere in nuclear physics—for example, in the torch that pushes this ship. So, they reasoned, the change in time rates must be real, because the corollary equations worked in practice. But nobody knew. You have to climb the tree and look."
"When will we know?" I was still worrying. Staying several years, Einstein time, in the ship I had counted on. Getting killed in the course of it, the way Uncle Steve said we probably would, I refused to worry about. But dying of old age in the Elsie was not what I had counted on. It was a grim thought, a life sentence shut up inside these steel walls.
"When? Why, we know right now."
"You do? What's the answer?"
"Don't hurry me, son. We've been gone a couple of weeks, at a boost of 124% of one gee; we're up to about 9,000 miles per second now. We still haven't come far—call it seven and a half light-hours or about 5,450,000,000 miles. It will be the better part of a year before we are crowding the speed of light. Nevertheless we have reached a sizable percentage of that speed, about five per cent; that's enough to show. Easy to measure, with the aid of you mind readers."
"Well, sir? Is it a real time difference? Or is it just relative?"
"You're using the wrong words. But it's 'real,' so far as the word means anything. The ratio right now is about 99.9%."
"To put it exactly," added Mr. O'Toole, "Bartlett's slippage—that's a technical term I just invented-his 'slippage' in time rate from that of his twin has now reached twelve parts in ten thousand."
"So you would make me a liar for one fiftieth of one per cent?" Babcock complained. "O'Toole, why did I let you come along?"
"So you would have some one to work your arithmetic," his assistant answered smugly.
Pat told me he did not want me around when they operated, but I came anyway. I locked myself in my room so nobody could disturb me and stuck with him. He didn't really object; whenever I spoke he answered and the it got to the deadline the more he talked… a cheerful babble about nothing and everything. It did not fool me.
When they wheeled him into surgery, he said, "Tom, you should see my anesthetist. Pretty as a sunny day and just lap size."
("Isn't her face covered with a mask?")
"Well, not completely. I can see her pretty blue eyes. 1 think I'll ask her what she's doing tonight."
("Maudie won't like that.")
"You keep Maudie out of this; a sick man is entitled to privileges. Wait a sec, I'll ask her."
("What did she say?")
"She said, "Nothing much," and that I would be doing the same for a few days. But I'll get her phone number."
("Two gets you five she won't give it to you.")
"Well, I can try... uh uh! Too late, they're starting in... Tom, you wouldn't believe this needle; it's the size of an air hose. She says she wants me to count. Okay, anything for a laugh… one... two… three..."
Pat got up to seven and I counted with him. All the way through I kept winding up tighter and tighter to unbearable tension and fear. I knew now what he apparently had been sure of all along, that he was not coming out of it. At the count of seven he lost track but his mind did not go silent. Maybe those around the operating table thought they had him unconscious but I knew better; he was trapped inside and screaming to get out.
I called to him and he called back but we couldn't find each other. Then I was as trapped and lost and confused as he was and we groped around in the dark and the cold and the aloneness of the place where you die.
Then I felt the knife whittling at my back and I screamed.
The next thing I remember is a couple of faces floating over me. Somebody said, "I think he's coming around, Doctor." The voice did not belong to anyone; it was a long way off.
Then there was just one face and it said, "Feeling better?"
"I guess so. What happened?"
"Drink this. Here, I'll hold up your head."
When I woke up again I felt fairly wide awake and could see that I was in the ship's infirmary. Dr. Devereaux was there, looking at me. "You decided to come out of it, young fellow?"
"Out of what, Doctor? What happened?"
"I don't know precisely, but you gave a perfect clinical picture of a patient terminating in surgical shock. By the time we broke the lock on your door, you were far gone-you gave us a bad time. Can you tell me about it?"
I tried to think, then I remembered. Pat! I called him in my mind. ("Pat! Where are you, boy?")
He didn't answer. I tried again and he still didn't answer, so I knew. I sat up and managed to choke out, "My brother ... he died!"
Dr. Devereaux said, "Wups! Take it easy. Lie down. He's not dead... unless he died in the last ten minutes, which I doubt."
"But I can't reach him! How do you know? I can't reach him, I tell you!"
"Come down off the ceiling. Because I've been checking on him all morning via the m-r's on watch. He's resting easily under an eighth grain of hypnal, which is why you can't raise him. I may be stupid, son—I was stupid, not to warn you to stay out of it—but I've been tinkering with the human mind long enough to figure out approximately what happened to you, given the circumstances. My only excuse is that I have never encountered such circumstances before."