Analog SFF, September 2009
Page 10
Several passengers sighed in relief.
"There's only one small problem,” said Danica. “We weren't using attitude rockets to stay pointed at the moon. We use gravity gradient stabilization—tidal forces. Basically, the long axis of the ship stays pointed at the moon because of the slight difference in the gravitational force on the near end as opposed to the far end."
"Oh,” said Mrs. Park.
"What if we made another hole near the nose?” said Mrs. Lyle. “Use some of our air to push us before plugging the hole?"
Danica frowned. “Maybe, if we had something that could make a hole through ten centimeters of diamondglass..."
"No,” said Bryson. “My A.I. says it wouldn't be enough even if we emptied all the atmo."
"Action and reaction. We need to find something to use as propellant, or else we can't turn the ship,” said Mrs. Park.
"Wait,” said Mr. Godfrey. “That's not true. I read a story once where an astronaut turned his ship one direction by spinning a wheel in the other direction at the ship's center of gravity."
"Yes!” Mrs. Park's voice was excited. “Conservation of angular momentum. It could work.” She looked at Danica. “Where's the center of mass on this ship?"
"It would be in the fuel tank, just above the main engine.” Something about the idea seemed to click in Danica's mind, but then she shook her head. “There's no way to access it from here, and even if there were—it's full of liquid hydrogen."
"What if we all got on one side of the ship, made it unbalanced, and then you turned the main engine on?” said Maddy. “Wouldn't that make it curve around?"
"A bit,” said Danica.
Bryson puffed in exasperation. “Not enough to keep us from smashing into the moon, picoceph."
"Well, forgive me for not having an A.I. to tell me how to be smart,” said Maddy.
"Quiet!” said Danica. “Arguing doesn't help."
"Nothing's gonna help,” said Bryson. “My A.I.'s smarter than all of us put together, and it's run all the scenarios. In thirty-six minutes we're going to crash. Get used to it."
Danica felt she should protest against hopelessness, but had no idea what to say.
"Ah, “The Cold Equations.'” Mr. Godfrey made a sound that seemed half chuckle, half sigh. “Did your A.I. calculate how many of us would need to jump out the airlock in order to change the ship's attitude?"
Bryson's eyes widened behind his visor.
"You can't be serious,” said Danica.
Mr. Godfrey smiled crookedly. “Deadly so. I volunteer myself as reaction mass, but I doubt I weigh enough on my own."
"Not enough,” said Bryson. “Even if all of us jumped, it's not enough."
"I've got it!” yelled Mr. Lyle. “It works! I think."
"What?” said Danica.
"The radio. I think I'm sending out an S.O.S.” Mr. Lyle tapped two wires together in rhythm. “Dot-dot-dot dash dash dash dot-dot-dot."
"So now we just sit back and wait for them to rescue us?” said Bryson's sister.
"There's a possibility that an ore freighter is in a nearby orbit,” said Danica. She figured it was only a five percent chance, but that was five percentage points more than they'd had before.
"Except the freighters are all grounded ‘cause the miners are on strike,” said Bryson.
"Don't blame this on the miners, boy,” said Mr. Lyle. “The working conditions—"
"Stop it,” said Danica.
"—are completely unsafe,” continued Mr. Lyle. “L.M.C. makes obscene profits while paying sub-standard wa—"
Bryson opaqued his visor.
"Enough!” Danica pointed at Mr. Lyle. “It doesn't matter now."
Mr. Lyle shut up.
"You can either keep sending the S.O.S. on the slim chance someone'll hear it.” Danica took a deep breath. “Or you can spend some time with your wife before the end."
He stopped clicking the wires together and looked over at his wife.
"Or,” Mrs. Lyle said, “you could do both. Keep trying—I'll come to you.” She unbuckled her seatbelt and pushed herself away from her seat, toward her husband in the middle of the cabin.
But her inexperience in zero-gee showed as her right hand caught for a moment on her loose seatbelt. She started spinning as she drifted through the air, and her instinctive move of clutching her arms to her chest only made her pirouette faster.
"Oh dear,” said Mrs. Lyle.
Bryson let out a slight chuckle, proving that he could still see through the opaqued visor.
Danica launched herself to rescue the poor woman. For a moment she pictured Mrs. Lyle as a ship, floating helpless in space, just like the Moonskimmer. Except Mrs. Lyle was spinning on her long axis...
"I've got it!” Danica shouted as she grabbed Mrs. Lyle by the arm. Their momentum carried them across the cabin, and Danica was able to catch a handhold and steady them both.
"We're going to survive,” Danica said firmly. “We just need to get the ship spinning on its long axis."
"How?” said Bryson.
Danica pointed at Mr. Godfrey. “Kind of like that story he mentioned. We use my chair in the center of the cabin. And we rotate ourselves around it like we're on one of those playground merry-go-rounds where you spin yourself around by hand power. We'll need everyone's mass for this—some of you will just have to hang on to the people in the middle doing the turning."
"Glad my idea helps,” said Mr. Godfrey, “but what good is it to rotate on the long axis? We'll still be pointed at the moon."
Danica turned to Mrs. Park. “Gyroscopic inertia."
Mrs. Park's eyes lit up. “Oh, of course. You all remember my example before? It was wrong because the tidal force kept pulling the long axis toward the moon. But if we're spinning on our long axis, gyroscopic inertia will resist that pull, just like a spinning gyroscope resists the pull of gravity trying to make it topple over."
"Mr. Lyle,” said Danica, “can you handle catching people there?"
"I can.” He anchored himself with one arm through the seatbelt strap, and Danica gave his wife a gentle push toward him.
"I don't believe it,” said Bryson.
Danica paused in making her way toward the next passenger. “Why not? I think it'll work."
"That's just it,” he said. He cleared his visor and looked at her with wide eyes. “My A.I. agrees with you."
Twenty-eight minutes later, and only 160 meters from the lunar surface, Danica activated the main engine. The Moonskimmer accelerated toward the clear space ahead, and the Moon gradually fell away beneath them. It was another eight hours before a tug from Luna City caught them.
Just before stepping into the airlock, Bryson turned back to Danica. “I'm not going to let my mom sue you."
Danica smiled wryly. “Thanks, I guess."
Bryson shrugged. “You know, my grandfather runs Sullivan Space Technologies."
"I suspected as much,” said Danica.
"He'll track down whoever was behind the sabotage, even if the police don't."
She nodded.
"Gramps just built a luxury cruise ship to go out to Saturn,” Bryson said. “He really wants me to go on the maiden voyage with him."
Puzzled as to why he was telling her this, Danica said, “Well, I hope our little adventure hasn't put you off tourism forever."
"Nah.” He shook his head. “I'm going to tell him I'll go—if he hires you as the pilot."
He stepped into the airlock, leaving Danica speechless.
Copyright © 2009 Eric James Stone
[Back to Table of Contents]
Reader's Department: THE ALTERNATE VIEW: THE TROUBLE WITH PHYSICS by Jeffery D. Kooistra
I won't keep you in suspense. I am going to highly recommend that you guys obtain and read a copy of Lee Smolin's The Trouble With Physics (Mariner Books, 2006. ISBN-13: 978-0-618-55105-7).
I did not know if I would like this book much when I started it. After all, Smolin is a regular physicist, and not
a heretic physicist. But he said some intriguing things in the Introduction and I began to get the hint even in the first chapter that when Smolin entitled his book, he was serious. He really meant the trouble with physics itself, as practiced in the last 30 years or so, and not unresolved problems physics still has left to explain (even though he does have his own list of five things).
I first discovered Lee Smolin when his book Three Roads to Quantum Gravity was offered by my book club. That one was well received and much better written than another string theory book I once wrote about (the overblown The Fabric of the Cosmos by Brian Greene, which I lambasted in my September 2005 Alternate View, “Allure-Free Strings"). So I was encouraged that Trouble might be right up my alley. Smolin is currently at the Perimeter Institute for Theoretical Physics, of which he is a founding member, and you can find out more about him at his website, www.leesmolin.com.
What drove him to write Trouble was the observation that, unlike in generations past, his generation of physicists hadn't accomplished much. After all, Maxwell's electrodynamics was followed by Einstein's relativity was followed by quantum mechanics was followed by nuclear physics and quantum electrodynamics and so on, every generation having done its share to add pieces to the puzzle of how the universe works. Just prior to Smolin's generation the standard model of particle physics was hammered out, and when he got his Ph.D. he had every right to assume that his generation would continue the illustrious pursuit, with similar successes along the way. But it didn't. This book exists as Smolin's explanation for what went wrong and what should be done to fix it. I should clarify at this point that when Smolin is talking about physics, most of the time he means theoretical physics, and more specifically, string theory and string theorists.
From my point of view, the last 30 years have been astonishingly successful in providing physicists with the tools they need to pursue knowledge. We've never been able to measure things more accurately, look at things more closely, or calculate more precisely than we can at this moment in history. For experimental, industrial, and computational physicists, this current generation is living through a golden age. We've sent robots to other planets, put observatories above the ocean of air, and learned how to manipulate matter one atom at a time. Soon we'll be taking quantum computing from the lab out into real life. But while doing all this, we haven't required anything recent from theoretical physics to guide us on our way. It was very soon after Maxwell predicted radio waves that radio was invented. Nuclear physics was still in its infancy when the first atomic bombs were built. But we've been messing around with string theories for over a quarter century now and so far the string theorists haven't provided us with one testable prediction, suggested any new technologies, or even been able to agree that there really is a string theory that applies to our universe.
Yet there is no shortage of praise for and faith in this thing called String Theory. Science articles and books discuss it as if we've already seen strings and branes and all seven of the extra dimensions. As an insider for part of his career, Smolin lays out in meticulous detail just what it is string theorists have been trying to do and how very far away they still are from reaching their goal.
The first half of the book deals with nothing but string theories. As Smolin points out, string theorists own the universities, and the new postdoc in theoretical physics had better be on board with the string theory program or his chances of obtaining a job, let alone tenure, at a university are pretty slim. Frankly, I found this part a bit tedious. For those of us who have been hearing or reading about string theory with increasing disdain for 30 years, we've already had more than enough of it. The accomplishments I listed above were brought about by scientists and engineers too busy with real matter on real test benches to keep paying attention to the latest exaggerated claims out of the string theory camp. On the other hand, I must admit I didn't appreciate just how much of a stranglehold string theory and theorists have on the halls of theoretical physics, at least here in the United States.
It is the second half of the book that makes me say that Analog readers would do well to see what Smolin has to say. Smolin shows that some of the practitioners of string theory, having spent their lives at it, want to “change the rules” about what constitutes doing science (they're willing to do without string theory ever being experimentally validated), rather than simply accept that string theory isn't the answer. He says: “It seems rational to deny this request and insist that we should not change the rules of science just to save a theory that has failed to fulfill the expectations we originally had for it. If string theory makes no unique predictions for experiments, and if it explains nothing about the standard model of particle physics which was previously mysterious—apart from the obvious statement that we must live in a universe where we can live—it does not seem to have turned out to be a very good theory. The history of science has seen a lot of initially promising theories fail. Why is this not another such case?"(p. 170)
See why I like this book? I could have said this! It just wouldn't mean as much coming from me since I've spent no time in the string theory trenches. But Smolin has and his love of physics and his concern for what his generation is leaving to the next motivated the book. As he says quite poignantly: “What has my generation bequeathed to these young scientists? Ideas and techniques they may or may not want to use, together with a cautionary tale of partial success in several directions, resulting in a general failure to finish the job that Einstein started a hundred years ago? The worst thing we could do would be to hold them back by insisting that they work on our ideas. So the question for the last part of the book is a question I ask myself every morning: Are we doing all we can to support and encourage young scientists—and by virtue of this, ourselves—to transcend what we have done these last thirty years and find the true theory that solves the five great problems of physics?"(p. 258)
Smolin thinks we are living in a revolutionary period (see successes listed above), but “we are trying to get out of it using the inadequate tools and organization of normal science."(p. 311) What we desperately need is for someone to come up with the missing revolutionary idea, to point out the mistake that has been made, to expose the false assumption that has gone unchallenged. Which brings him to ask this question: “Do we have a system that allows someone capable of ferreting out that wrong assumption or asking the right question into the community of people we support and (equally important) listen to? Do we embrace the creative rebels with this rare talent, or do we exclude them?"(p. 309)
Smolin breaks theoretical physicists into two categories, the craftspeople and the seers, and describes them like this:
"Master craftspeople and seers come to science for different reasons. Master craftspeople go into science because, for the most part, they have discovered in school that they're good at it. They are usually the best students in their math and physics classes from junior high school all the way up to graduate school, where they finally meet their peers. They have always been able to solve math problems faster and more accurately than their classmates, so problem solving is what they tend to value in other scientists.
"Seers are very different. They are dreamers. They go into science because they have questions about the nature of existence that their schoolbooks don't answer. If they weren't scientists, they might be artists or writers or they might end up in divinity school. It is only to be expected that members of these two groups misunderstand and mistrust each other."(p. 310)
This last sentence is key to understanding just exactly what the trouble with physics is today and it's worth taking the time to understand it.
The one scientist whom most people have heard of is Albert Einstein. When someone hears the word “genius” it is his image that comes to mind. But Einstein was far from being anything like a typical physicist. He worked on foundational matters in physics—it doesn't get any more foundational than “What is space and time?” But most physicists do not, and Smolin encapsulates the mindset he gre
w up with in this tragic, yet all too accurate passage: “When I learned physics in the 1970s, it was almost as if we were being taught to look down on people who thought about foundational problems. When we asked about the foundational issues in quantum theory, we were told that no one fully understood them but that concern with them was no longer a part of science. The job was to take quantum mechanics as a given and apply it to new problems. The spirit was pragmatic; ‘Shut up and calculate’ was the mantra. People who couldn't let go of their misgivings over the meaning of quantum theory were regarded as losers who couldn't do the work."(p. 312)
This is how the geocentrists treated Copernicus; as if he couldn't calculate planetary positions via epicycles, so he wasted his time inventing fanciful ideas about planets circling the Sun instead. This then is the crux of the matter—the kind of seer most likely to see what physicists have been missing for the last 30 years is also the kind least likely to get hired, let alone respected, in academia.
Early in the book (pp. 49-50) Smolin relates how his first job after getting his Ph.D. was at the Institute for Advanced Study in Princeton. He had hoped in some way to touch Einstein's legacy there. One of the few people still there from Einstein's days was Freeman Dyson. When Smolin asked him what Einstein was really like, Dyson couldn't help him. Dyson said that he, too, had wanted to meet Einstein, and even had set up an appointment. But prior to the meeting, he had obtained some of Einstein's recent papers on unified field theory, and upon reading them decided they were junk. Dyson skipped the appointment and avoided Einstein for the next eight years until the great man died.