Analog SFF, July-August 2008

by Dell Magazine Authors

  “Are you saying that tachyons actually exist and you've actually been able to detect and manipulate them?”

  “Well, no. Not directly. But Gell-Mann's Law says that if something is not forbidden by physics, it must exist.” Bing laughed. “Gell-Mann proposed it as sort of a joke, but it's predicted a lot of good stuff.”

  “Stuff?” said Colin.

  “Like tachyons. In theory, they interact with, and only with, gravitons. And so...” Bing spread his arms in a pantomimed “ta-da.” “And so using focused, coherent gravitons, we've been able to modulate and demodulate those theoretical tachyons. And so we'll be able to transmit stuff to these aliens—we think.”

  “You think!”

  “It's the best I can do, I'm afraid,” said Bing with a smile.

  “But that means you've no idea where these aliens might be?” said Colin.

  “Absolutely none. They could be across the galaxy, although probably not—farther is more probable. They could be across the universe or even off in another pocket universe. Especially as the speed of light isn't even a defined concept when going from one pocket universe to another.” He looked quizzically at Colin. “You do know what pocket universes are, don't you?” He didn't wait for an answer, but pointed to the plaque above the window. “What is that?”

  “That?” Colin followed Bing's gaze. “That is a representation of Saint Brigit's Cross.”

  “Doesn't look much like a cross to me.”

  “Well, it is. Saint Brigit made it out of rushes on short notice.” Colin noticed his new colleague's baffled expression and tried to explain. “We Irish often hang one over a doorway to bring luck.” He lowered his gaze from the cross to the window below it. “Snow,” he said in a tone of disgust.

  “Hardly unexpected,” said Bing, “in New York City in January.”

  Colin glowered at the unwelcome whiteness. “Maybe Saint Brigit will bring the good luck of an early spring.”

  Bing laughed. “You know,” he said. “Niels Bohr used to tell the story of friends who had a horseshoe over their door for luck. Bohr asked them, ‘You don't genuinely believe in that, do you?’ and they answered. ‘No. Of course not, but we've been told it works whether you believe it or not.'”

  Colin forced a thin smile. “My belief,” he said evenly, “might be a bit more spiritual.”

  Bing looked at first astonished, and then mortified.

  “Oh, come,” said Colin in some amusement. “I'm sure you've run into believers before—even among you physicists.”

  Bing's expression morphed to sheepishness, and then to inquisitiveness. “Look,” he said. “I'm sorry, but I—”

  “It's all right.” Colin spoke more abruptly than he'd intended.

  “But I wonder,” Bing went on, tentatively. “Do you ... Are you a creationist?”

  “You mean do I believe God created the universe? Yes, I do. Absolutely. Without doubt.”

  “It must be good to believe in something absolutely,” said Bing with an almost wistful expression. “What faith I have, I place in science.”

  “There are many degrees of creationism,” Colin said almost by rote; he'd had this conversation many times before with scientists. “I believe God's creation of the universe followed the precepts of science. After all, he created science.”

  “But what gives you the certainty?” Bing insisted. “Is it because you believe, as I've heard creationists maintain, that the eye, for example, is too complicated to have happened purely through evolution?”

  Colin gave a rough laugh. “The evolution of the eye? Irrelevant! I've no problem with evolution. But just look around you.” He gestured, expansively. “That proves the existence of God.”

  “What?” There was a challenge in Bing's voice. He gestured as well. “You mean your desk, the bookshelves, the blackboards?” He nodded toward the window. “Or do you mean the Earth, the sky, the flowers, the—”

  “To hell with the flowers,” Colin barked out. “I hate flowers. I have allergies. What I mean is the fine structure constant, Planck's constant, the properties of the elementary particles, and most critically, the cosmological constant.”

  “You know a lot of big physics words,” said Bing in a voice at the boundary between anger and jest, “considering you're a mathematician.”

  Colin, rising to anger despite himself said, “If the cosmological constant were minutely different from its God-given value, then life and even chemistry would be impossible.”

  “Ah, the anthropic principle,” said Bing with a sigh. “The idea that the probability of a livable universe developing by chance is essentially zero. The idea that only God could have created such an unlikely universe.”

  “Yes. Most definitely yes,” said Colin. “There can be no other logical solution.”

  “Look,” said Bing. “You can believe in anything you like—as long as you don't confuse belief with science.”

  “Damn it, this is science,” Colin growled. “The fine-tuned value of the cosmological constant. There is no possible way it could have happened by chance.”

  “In fact, there is,” said Bing, clearly suppressing anger.

  “Do tell me.” Colin's voice dripped sarcasm. “I'm all ears.”

  “I'm sorry if I've offended you,” said Bing. “I didn't mean to. Let's discuss this like intelligent beings.”

  Colin gritted his teeth, then decided he'd not let Bing take the high ground alone in the issue of Christian charity and forgiveness. “I'm sorry as well,” he said, struggling for a smile. “I'm afraid I have something of a temper. A congenital condition, I'm afraid.” Colin knew he was being disingenuous. He was not about to tell Bing that when his mother was taken from him, his faith had wavered. He'd challenged God to provide a reason to believe in Him and, years later, when he was old enough to understand it, God provided the cosmological constant.

  “All right,” said Colin with a sigh. “Let's hear your explanation of how our universe can exist.”

  “Not my explanation, exactly,” said Bing with no lingering hostility in his voice. “It's Leonard Susskind's formulation of string theory. Susskind says that up until a few years ago, there were only five or six possible Calabi-Yau manifolds: solutions to the string theory equation describing the universe. Now they estimate that there are over ten to the five hundred solutions—a googol to the fifth.” Bing's eyes all but glowed with fervor. “And most of these solutions might actually exist as distinct pocket universes in a vast megaverse. A vast landscape of possible solutions—of universes. Each of these universes could have different values of the physical constants and could even have different numbers of uncompacted dimensions. So, by virtue of there being so many universes, some of them will, by chance, be right for us. And we're in one of those.”

  “Come on,” said Colin. “Be serious. Different numbers of dimensions? This Susskind is crazy.”

  “Oh,” said Bing, “you know him then, do you?”

  “Do you really consider this physics?” said Colin. “My God! Ten to the five hundreds of universes with differing physical constants—and differing dimensions?”

  “Well, all universes have ten dimensions, we think,” said Bing, “or eleven if you accept m-brane theory. But some of them are compacted, folded, too compact to measure. At a scale of ten to the negative thirty three centimeters or thereabouts.”

  “What the hell is a compacted dimension, really?” said Colin, making no attempt to keep incredulity out of his voice. He was actually glad though, that they were getting away from theology. He was pretty sure Bing felt the same way.

  Bing looked at him with a puzzled expression.

  “I mean to say that I have only a layman's familiarity with the term. I'm a specialist in information theory and complex analysis, but I'm not a differential geometrist or topologist.”

  “It's actually easy to visualize,” said Bing. “Imagine this office having a 3-dimensional coordinate system—we'll use polar coordinates.” He touched the tip of his nose.
“To specify the coordinates of my nose, you'd need two angles and a radius line from the corner of the room—the origin of the coordinate system—to the tip of my nose.” He twitched his nose like a rabbit. “But string theory says there is no such thing as ‘points’ in space, so that radius has to be thought of not as a line, but as a very thin rod. And with a rod, there's another dimension—the angle around the rod. QED, a 4-dimensional coordinate system. Of course, in a universe of six or seven compacted dimensions, things get a lot more complicated.”

  Colin stared with amused incredulity. “This sounds like fiction—just another way for some physicists to try to deny the existence of God.”

  “No,” Bing protested, “just taking the need for God out of physics. You can have God. It's no problem.” He paused. “Although, for reasons of physics, I think any god would be restricted to the particular pocket universe he was in.”

  “What?” Despite himself, Colin laughed. “No! You're missing the whole idea of God. God is not a localized phenomenon.”

  “Sorry.”

  Just then, the phone rang. Colin, thankful for the diversion, answered it. When he hung up, he announced, “Jake is back with the nitrogen.”

  Bing jumped to his feet. “Great! Let's go.” Colin stood as well, but more slowly and with dignity.

  “You know,” said Bing, glancing at the door in obvious impatience, “after a couple of years trying, this is the first signal we've ever received. I think you've brought us luck.”

  “Oh?” Colin couldn't help smiling. “You don't genuinely believe in that, do you?”

  “Touche!” Bing chuckled. “Perhaps I do. We physicists tend to be superstitious—ritually superstitious.” He started for the door, but Colin asked him to hold up a moment.

  “I've heard it said,” said Colin, solemnly, “that two people can't become true friends until they've had a knock-down, drag-out, shouting argument with each other.”

  Bing nodded, then stuck out his hand. “Friends?”

  Colin clasped it. “Friends!” He paused. “But I still believe.”

  “No problem,” said Bing. “Belief isn't subject to science or rational thought.”

  “Descartes was a rationalist,” said Colin. “And he did prove the existence of God—using logic and rationality.” He urged Bing on toward the door. “Simply put, a belief in God is more rational than a belief in science.”

  “I think that's backwards,” said Bing looking over his shoulder, his serious expression contradicted by a crack in his voice. “You're putting Descartes before the horse.” He darted through the door.

  Colin threw a glance to the ceiling. “Give me strength!”

  * * * *

  Colin, following Bing into the Farcast lab, again heard the hum. Even though it indicated the alien presence was still transmitting, he found the sound disquieting.

  He saw Katya fiddling with some equipment next to the display monitor. Then he noticed that the line printer had streamed more paper to the floor. Apparently the prime numbers were still coming through. Neville, standing next to the printer examining the printout, caught Colin's gaze. “Strange, in a way,” said Neville. “The data stream is absolutely constant.”

  “In what way, strange?” said Colin.

  “I would have expected some noise in the data stream,” said Neville, his eyes on the printout, “some suggestion of stochasticity. The fact that it's missing suggests that the source is very distant—implying a total uncertainty of its position.”

  Bing walked up. “Evidence perhaps that the signal might be from another pocket universe?”

  “Quite possibly.”

  “This is great!” Bing turned to a rack-mounted instrument cluster next to the printer. He peered at a circular dial calibrated in degrees K. The needle stood at 270. “Brr,” he said. “It's cold on the roof.”

  Neville glanced at the dial. “About twenty-six or twenty-seven degrees Fahrenheit. Yes. A bit chilly.”

  “I thought Jake had gotten the liquid nitrogen,” said Bing.

  “He's just gone up to the roof with it.”

  “You really believe in these multiple universes?” said Colin, annoyed for some reason at how matter-of-factly his colleagues discussed the issue.

  “I don't disbelieve in them.” Neville gave a tight-lipped smile. “I gather you are a skeptic.”

  “I've never been called that before.” Colin nodded. “But pocket universes, higher dimensionality. Yes. I admit having difficulty believing it.”

  “Well, our aliens could possibly be in a ... in a galaxy, far, far away. Where have I heard that phrase before? But the megaverse is so much larger than our universe, I think the odds of the signal coming from another pocket universe are much greater.”

  “As I said, I have trouble with the idea.”

  Neville chuckled. “Then I guess you don't think much of ... oh, I can't remember who did it, but of the calculation that a god cannot exist in only four uncompacted dimensions.”

  “What?” Colin shot Bing an exasperated glance.

  Again, Neville chuckled. “Sorry,” he said. “I ran down to my office for some aspirin and couldn't help hearing some of your philosophical disputations through the wall.”

  “Ah,” said Bing, pointing to the temperature dial. “There it goes.”

  Colin turned his gaze to the dial and watched as the needle vibrated and moved slowly counterclockwise. “How low will it get?”

  “Nitrogen boils at 77.2 degrees Kelvin,” said Bing.

  “It's cooling down now, Katya,” Neville called over to the Farcaster control console. “Should be ready in about ten minutes.”

  “I ready now,” Katya called back.

  * * * *

  Fifteen minutes later, Neville sat gazing at the monitor with his finger on a pushbutton. Colin standing with Bing and Katya behind, noticed that the finger shook.

  “This is it,” said Neville, softly. “I hope we're...”

  “Go for it,” said Bing in a voice softer still.

  "Udachi!" whispered Katya. “Good luck!”

  Silence pervaded the lab—save for the hum. Then Colin heard the chirps and saw the string of primes ending in 19 displayed in white on the monitor.

  “Here goes,” said Neville. He pushed the button twenty-three times in quick succession. His pulses displayed green on the monitor.

  They stared in silence at the monitor. After five seconds or so, Neville said, nervously, “God, I hope I actually sent twenty three.”

  “You did,” said Katya with a smile. “I counted on monitor.”

  Then, at about the fifteen-second mark, there came a chirp and the monitor displayed:

  -.- .-.-. .

  “A response!” Neville shouted.

  “This is great!” said Bing. “We're communicating!”

  “But what it mean, I wonder,” said Katya. “Short blips and long blips.”

  They stared at the screen until, about fifteen seconds later, another chirp came:

  .-.-. ..

  Fifteen seconds later came nothing. But then after another fifteen seconds, they saw,

  .-.-. ...

  “What do you make of that?” said Neville.

  No one answered.

  About forty-five seconds later came the next transmission:

  .-.-. ....

  “It's got to be a message about time,” said Bing after about half a minute. “The short long short long short might mean the LGM will transmit its next message in n time units, and the short short short short is the number of time units.”

  “Could be,” said Neville. “Yes. Delay of n time units. Good.”

  The next message came a little over one minute later:

  .-.-. .....

  “Looks like you're right,” said Neville. “Each transmission comes with a delay one woof later than the last.”

  “Yeah.” Bing threw a glance to Colin. “Looks like you've added woof to our vocabulary.”

  “I wonder,” said Neville, pointing to t
he -.- .-.-. . higher up on the screen, “what that initial symbol might mean, the dash dot dash.”

  No one answered.

  The chirps came in at an ever slower pace until, after the delay associated with the .-.-. ............ transmission, they received:

  ——

  “What do you make of that?” said Colin, rhetorically.

  After five minutes of no transmissions, Bing said, “Maybe they're waiting for us to respond.”

  “Quite possibly,” said Neville, “but we can only send dots.”

  “Then I think we should send the next prime.”

  “Twenty-nine,” said Colin.

  “Okay.” Neville pushed the button twenty-nine times. A few seconds later, an answer came:

  -.- ——

  After staring at it for a minute or so, Colin said, “My guess would be that dash dot dash means ‘acknowledged’ or ‘correct’ and dash dash dash dash means ‘over.'”

  “I agree,” said Neville. He pulled open a drawer and withdrew a lab notebook. “I think we'd better start a dictionary.”

  “What we send our new friends now?” said Katya.

  “I suggest we send nothing,” said Bing. “Not until we can send dots and dashes, and at the speed they're sending them to us.”

  “Agreed.” Neville glanced at his watch. “But, damn it, it's after five, and a Friday. I'm sure everyone but us has bailed for the weekend. We'll have to do it ourselves.” He furrowed his brow and looked off into the distance. “Bing and I can do the computer programming,” he said to no one in particular. Neville stood. “Katya,” he said. “Can you whip up something to drive the transmitter from a computer data stream?”

  “Da. Of course. I am experimentalist.” She glanced over at a lab bench. “Must solder connector and configure microprocessor chip.” She headed for the bench. “You must give me data as USB-IV.”

  “Done,” said Neville. “Let's get going.”

  In spite of the camaraderie of the small group, Colin had no doubt as to who was in charge.

  “Neville,” said Colin. “I can help with the programming. I'm good at that sort of stuff.”

  “Terrific,” said Neville. He darted to a phone and, with great solemnity, ordered delivery of a couple of pizzas.