including herself and her companions— looked quite ordinary. Well, maybe a bit excited. But they were not yet long thin threads.
These were idle ruminations, she knew. The physics of black holes was not her field. Anyway, she could not understand how this could have anything to do with black holes, which were either primordial—made during the origin of the universe—or produced in a later epoch by the collapse of a star more massive than the Sun. Then, the gravity would be so strong that—except for quantum effects—even light could not escape, although the gravitational field certainly would remain. Hence “black,” hence “hole.” But they hadn't “collapsed a star, and she couldn't see any way in which they had captured a primordial blackhole. Anyway, no one knew where the nearest primordial black hole might be hiding. They had only built the Machine and spun up the benzels.
She glanced over to Eda, who was figuring something on a small computer. By bone conduction, she could feel as well as hear a low-pitched roaring every time the dodec scraped the wall, and she raised her voice to be heard. “Do you understand what's going on?”
“Not at all,” he shouted back. “I can almost prove this can't be happening. Do you know the BoyerLindquist coordinates?”
“No, sorry.” “I'll explain it to you later.” She was glad he thought there would be a “later.” Ellie felt the deceleration before she could see it, as if they had been on the downslope of a roller coaster, had leveled out, and now were slowly climbing. Just before the deceleration set in, the tunnel had made a complex sequence of bobs and weaves. There was no perceptible change either in the color or in the brightness of the surrounding light. She picked up her camera, switched to the long-focal-length lens, and looked as far ahead of her as she could. She could see only to the next jag in the tortuous path. Magnified, the texture of the wall seemed intricate, irregular, and, just for a moment, faintly self-luminous.
The dodecahedron had slowed to a comparative crawl. No end to the tunnel was in sight. She wondered if they would make it to wherever they were going. Perhaps the designers had miscalculated. Maybe the Machine had been built imperfectly, just a little bit off; perhaps what had seemed on Hokkaido an acceptable technological imperfection would doom their mission to failure here in… in wherever this was. Or, glancing at the cloud of fine particles following and occasionally overtaking them, she thought maybe they had bumped into the walls one time too often and lost more momentum than had been allowed for in the design. The space between the dodec and the walls seemed very narrow now. Perhaps they would find themselves stuck fast in this never-never land and languish until theoxygen ran out. Could the Vegans have gone to all this trouble and forgotten that we need to breathe? Hadn't they noticed all those shouting Nazis?Vaygay and Eda were deep in the arcana of gravitational physics—twistors, renormalization of ghost propagators, time-like Killing vectors, non-Abelian gauge invariance, geodesic refocusing, elevendimensional Kaluza-Klein treatments of supergravity, and, of course, Eda's own and quite different superunification. You could tell at a glance that an explanation was not readily within their grasp. She guessed that in another few hours the two physicists would make some progress on the problem.
Superunification embraced virtually all scales and aspects of physics known on Earth. It was hard to believe that this… tunnel was not itself some hitherto unrealized solution of the Eda Field Equations.
Vaygay asked, “Did anyone see a naked singularity?”
“I don't know what one looks like,” Devi replied. “I beg your pardon. It probably wouldn't be naked.
Did you sense any causality inversion, anything bizarre—really crazy—maybe about how you were thinking, anything like scrambled eggs reassembling themselves into whites and yolks…?”
Devi looked at Vaygay through narrowed lids. “It's okay,” Ellie quickly interjected. Vaygay's a little excited, she added to herself. “These are genuine questions about black holes. They only sound crazy.”
“No,” replied Devi slowly, “except for the question itself.” But then she brightened. “In fact it was a marvelous ride.”
They all agreed. Vaygay was elated.
“This is a very strong version of cosmic censorship,” he was saying. “Singularities are invisible even inside black holes.”
“Vaygay is only joking,” Eda added. “Once you're inside the event horizon, there is no way to escape the black hole singularity.”
Despite Ellie's reassurance, Devi was glancing dubiously at both Vaygay and Eda. Physicists had to invent wordsand phrases for concepts far removed from everyday experience. It was their fashion to avoid pure neologisms and instead to evoke, even if feebly, some analogous commonplace. The alternative was to name discoveries and equations after one another. This they did also. But if you didn't know it was physics they were talking, you might very well worry about them.
She stood up to cross over to Devi, but at the same moment Xi roused them with a shout. The walls of the tunnel were undulating, closing in on the dodecahedron, squeezing it forward. A nice rhythm was being established. Every time the dodec would slow almost to a halt, it was given another squeeze by the walls.
She felt a slight motion sickness rising in her. In some places it was tough going, the walls working hard, waves of contraction and expansion rippling down the tunnel. Elsewhere, especially on the straightaways, they would fairly skip along.
A great distance away, Ellie made out a dim point of light, slowly growing in intensity. A blue-white radiance began flooding the inside of the dodecahedron. She could see it glint off the black erbium cylinders, now almost stationary. Although the journey seemed to have taken only ten or fifteen minutes, the contrast between the subdued, restrained ambient light for most of the trip and the swelling brilliance ahead was striking. They were rushing toward it, shooting up the tunnel, and then erupting into what seemed to be ordinary space. Before them was a huge blue-white sun, disconcertingly close. Ellie knew in an instant it was Vega.
She was reluctant to look at it directly through the long-focal-length lens; this was foolhardy even for the Sun, a cooler and dimmer star. But she produced a piece of white paper, moved it so it was in the focal plane of the long lens and projected a bright image of the star. She could see two great sunspot groups and a hint, she thought, a shadow, of some of the material in the ring plane. Putting down the camera, she held her hand at arm's length, palm outward,to just cover the disk of Vega, and was rewarded by seeing a brilliant extended corona around the star; it had been invisible before, washed out in Vega's glare.
Palm still outstretched, she examined the ring of debris that surrounded the star. The nature of the Vega system had been the subject of worldwide debate ever since receipt of the prime number Message. Acting on behalf of the astronomical community of the planet Earth, she hoped she was not making any serious mistakes. She videotaped at a variety of f/stops and frame speeds. They had emerged almost in the ring plane, in a debris- free circumstellar gap. The ring was extremely thin compared with its vast lateral dimensions. She could make out faint color gradations within the rings, but none of the individual ring particles. If they were at all like the rings of Saturn, a particle a few meters across would be a giant. Perhaps the Vegan rings were composed entirely of specks of dust, clods of rock, shards of ice.
She turned around to look back at where they had emerged and saw a field of black—a circular blackness, blacker than velvet, blacker than the night sky. It eclipsed that leeward portion of the Vega ring system which was otherwise—where not obscured by this somber apparition—clearly visible. As she peered through the lens more closely, she thought she could see faint erratic flashes of light from its very center.
Hawking radiation? No, its wavelength would be much too long. Or light from the planet Earth still rushing down the tube? On the other side of that blackness was Hokkaido.
Planets. Where were the planets? She scanned the ring plane with the long-focal-length lens, searching for embedded planets—or at least for the home of the beings who had broadcast the Message. In each break in the rings she looked for a shepherding world whose gravitational influence had cleared the lanes of dust.
But she could find nothing.
“You can't find any planets?” Xi asked. “Nothing. There's a few big comets in close. I can see the tails.
But nothing that looks like a planet. There must bethousands of separate rings. As far as I can tell, they're all made of debris. The black hole seems to have cleared out a big gap in the rings. That's where we are right now, slowly orbiting Vega. The system is very young—only a few hundred million years old—and some astronomers thought it was too soon for there to be planets. But then where did the transmission come from?”
“Maybe this isn't Vega,” Vaygay offered. “Maybe our radio signal comes from Vega, but the tunnel goes to another star system.”
“Maybe, but it's a funny coincidence that your other star should have roughly the same color temperature as
