3
SCHWARZSCHILD RADIUS
Where in hell could her prole have been going?
For maybe the fifth time that night, Marianna Bonaventure sat up in bed and turned on the nightstand lamp. Not that her cramped government-rate hotel room was much to look at, but the light helped push back the thoughts that kept crowding in on her in the dark. Thoughts that began prosaically enough, on a sidewalk in lower Manhattan — not so many hours ago, not so many city blocks away from where she now lay, sleepless at three in the morning — thoughts that then mutated into a nightmare montage of breathless cross-town pursuits, rooftop confrontations, elevator shafts —
Shit! Even the light wasn’t helping. She switched it off and flopped back against the pillow again. Think about something else, Marianna, think good thoughts. Good thoughts like
Ghostly scrawls — S-curves and tridents, angle-brackets and lissome, leaf-like glyphs — inscribed the darkness. Puzzle-pieces from a primeval alphabet known as Linear A, whose still-undeciphered secrets, and those of the Bronze Age Minoan civilization that devised it, had held a lifelong fascination for her father, Jeremy.
Her eyelids fluttered closed. Behind them, another vision took shape, a cratered crescent rising out of the sea. Marianna’s lips shaped a word, though no sound came out: “Thira.”
The isle of Thira, where everything was to begin, was where everything had once come to an end. In the year 1450 BCE, it had been the locus of a volcanic eruption. An eruption so great it not only vaporized the core of the island itself but spawned the earthquakes and tidal waves that brought the Aegean Golden Age to a cataclysmic close, and gave rise to legends of lost Atlantis.
What little remained of Thira might have gone on slumbering in the Mediterranean sun forever, save that in 1967 the ruins of the ancient Minoan seaport of Akrotiri had been discovered there, entombed like Pompeii beneath tons of lava and ash. With new inscriptions being unearthed almost daily in the ongoing excavation, Thira became a magnet for Linear A scholars from around the world. Including, in the mid-seventies ...
Jeremy Bonaventure, ink still drying on his doctorate in classical civilizations, was eager to try his luck in the hunt for the Minoan equivalent of a Rosetta Stone. Crete was only to be a brief stopover en route, until he met the guide the Cretan Antiquities Administration had assigned him.
Ariadni Kalimanakis was a raven-haired beauty almost thirteen years Jeremy’s junior. A first-year archaeology major interning that summer at the museum in Iraklion, she had, thanks to her excellent English, been stuck with the job of babysitting a shy, bookish American.
Marianna smiled in her half-sleep at the unlikely pair, the scion of San Francisco society and the Greek fisherman’s daughter, touring the palaces at Knossos, the dig at Taras — anywhere and everywhere the tablets, door lintels, and other artifacts bearing traces of Linear A were to be found. It was mid-July before they finally boarded a packet-boat for the day-long trip to Thira.
Ariadni remained lost in thought all through that long afternoon, but by the time they docked she had made her choice. She knew full well it could spell ruin, not only for her own reputation, but for the honor of her family. Yet over the past weeks she had grown to love Jeremy for his gentleness, his breadth of mind, his depth of spirit. And she was not one to deny her deepest feelings, no matter the cost.
At sunset they left their pensìon and wandered up into the gentle, grassy hills above the village of Emborion. There, on that warm July night, with the full moon a shield of beaten silver rising out of Homer’s wine-dark sea, she gave herself to him.
It was a love story Marianna had heard again and again, told in less and less sanitized versions as she grew from childhood to adolescence. Told in exotic accents by a mother young enough almost to be an elder sister. In Marianna’s youthful imagination, this mythos, set at the fountainhead of a romance that still quietly infused her parents’ lives, came to take on the dimensions of an ancient archetype, of mysteries already old when the first Aegean civilization was fresh and new. Once she grew old enough to have the biological details more or less sorted out, she used to fantasize that she had been conceived on that first moon-drenched midsummer night.
Against all expectations, for all their differences of age and origin and temperament, Jeremy and Ariadni had made a life together. A life together filled with joy and learning, twin legacies they had bequeathed to their daughter, their only child. A life together tragically cut short on April 17th 1993, when they chanced to be on Hellenic flight 803 from New York to Athens.
Marianna rolled over and checked the clock on the nightstand again. Half-past three, and she had to be up by six. Up and back on the job, back trying to salvage what she could from the wreckage of her investigation, from the wreckage of her life
The crash investigators were never able to determine if it had been a suicide mission or just a run-of-the-mill hijacking gone terribly awry. All they had to go on were the screams and curses — and the echoing gunshots — on the cockpit voice recorder. That, and the physical evidence strewn across a mountainside in Switzerland: 13,786 twisted pieces of Boeing 747, ranging in size from a tabletop down to a matchbook.
The two people Marianna had loved most in all the world. Who had loved each other more and better than anyone she’d ever known. And all of a sudden they were just — gone.
A hard lesson for someone only eighteen years old, for anyone at any age: Don’t even try holding on to those you love. You can’t.
Love dies.
In the waters off the island of Thira, where everything had once begun, everything came to an end. Marianna stood alone at the stern of her grandfather’s fishing boat and scattered the ashes of her mother and father wide across their beloved wine-dark Aegean. No ceremony. No prayers. Nothing.
Nothing but a single truth.
Love dies.
Yuri Vissarionovich Geladze had no eye for understated elegance, else he could not have failed to discern it in Rusalka’s spacious, high-ceilinged headquarters suite with its varnished, quarter-sawn anigre paneling and matching leather-topped desk. Or in the graying, ruddy-faced man seated behind that desk, draped in a caramel Lanvin blazer, its golden highlights complementing his cream-colored shirt and matching silken cravat. In the whole room, the only item that looked out of place was a distorted metal cylinder, no longer than a pencil and perhaps twice as thick, resting in the man’s manicured hands.
“You sent for me,” Yuri said. Not a question, merely a statement of fact.
Arkady Grigoriyevich Grishin, CEO and Chairman of the Board of Grishin Enterprises International, seemed not to hear. His fingers continued stroking the engraved surface of his talisman. For long moments still his gaze was held by the scene out the panoramic window to his left: a flotilla of small boats, their sails aglow in early morning light, wending their way upriver toward the gray towers of a suspension bridge. It was with seeming reluctance at relinquishing the view that Grishin sighed, pushed his chair back, and looked up.
“Ah, yes, Yuri. Thank you for coming so quickly.” The voice was quiet, cultured, pitched just above a whisper.
Yuri nodded impassively.
“To begin —” Grishin leaned back in his chair, and favored Yuri with one of his dazzling smiles. “Permit me to congratulate you on yesterday’s twofold success: a false trail for CROM and their lead investigator dead, all at once.”
Yuri permitted himself a tight smile. “Two flies with one slap,” he said.
“Yes, exactly. Ah, of course, Postrel’nikova herself is to learn nothing of this action on her behalf. Not even Sasha can be told.”
That didn’t merit a response. It wasn’t as if Yuri had, or sought, any social contact with the Project’s chief scientist or its head planner.
“In any case,” Grishin went on, “that is not why I asked you here. It seems another matter has arisen. Merkulov’s people have been tracking it for some time. I had been waiting for them to make some show of initiative on their own, but then,” Grishin’s handsome, regular features rearranged themselves to hint at a frown, a jewel encrusted ring sparkled as his tanned hands pantomimed an indulgent helplessness. “Well, you know Vadim.”
“Yes.” Yuri shrugged. One might as well wait for some show of initiative from a stone as from Vadim Vasiliyevich Merkulov. The GEI security chief’s energies were directed, first and foremost, at protecting his own fat ass. It was, in fact, Merkulov’s continual reluctance to do the necessary that had led to Yuri’s engagement in the first place.
“Then this arrived.” Grishin looked down at the warped metal object resting in his hands. “Apparently the matter is more critical than we had thought. I fear you must miss tomorrow night’s gala in consequence.” He sighed as if breaking this sad news to an honored guest. “Vakhtang will coordinate security in your stead. Please brief him on the status of in-transit and on-site arrangements. But do so quickly. You must leave within the hour — there is a long way to go, in little time.”
Grishin nodded at the travel documents on Yuri’s side of the desk. Yuri took them and glanced over the itinerary: New York to Moscow to Krasnoyarsk to someplace called — Tunguska?
“And here,” Grishin handed him a sheet of thick, creamy paper, folded over twice, “is your subject.” In situations such as these, Grishin exhibited a certain delicacy: he would not speak the name of the victim in the presence of the assassin.
Yuri unfolded the sheet. Clipped to it were several color images — full, three-quarter, and profile shots of a thin, middle-aged man wearing tee-shirt, jeans jacket, and an American cowboy hat. The paper itself contained a single line of type. Unfamiliar English words, transliterated into a Cyrillic approximation. He sounded it out slowly:
“Professor Dzhek Adler. University of Teksas.”
As the old Mikoyan-3 helicopter rattled its way into the heartlands of the Stony Tunguska, Professor Jack Adler’s faded blue eyes drank in the vista he’d come so far to see.
When he really got fired up, Jack’s forty-something, borderline-ugly face — a little too narrow in the jaw, too thin in the lips, too broad at the forehead — radiated an intensity that made him seem almost young and good-looking. And right now he was wholly transfigured by the scene passing before his eyes. For, through gaps in the successor-growth canopy, he could see all the way down to the forest floor. Down to where the old forest lay strewn at the young one’s feet, its rotting trunks all aligned radially inward, pointing like thousands of directional arrows toward The Epicenter.
Toward the secret heart of the cosmic mystery of the millennium.
They would not be following the path pointed by those arrows today. Instead, the copter was skirting the Great Swamp’s southwestern perimeter headed for Kulik’s Landing. By craning his neck, Jack could just make it out up ahead.
From the air, the Landing on the banks of the sluggish Khushmo River hardly looked like the base camp for this year’s high-tech Tunguska expedition. More like a pioneer outpost, and a deserted one at that. Its scattering of rude log structures stood baking in the ninety-five-degree heat of a Siberian midsummer afternoon, silent and seemingly as forsaken as they had been throughout most of the seventy-odd years since the explorer Leonid Kulik had first built them. Only a pall of woodsmoke gave any evidence of human habitation.
The pilot set the Mi-3 down gingerly, as if the ground might buckle beneath its runners. Not an unreasonable concern: The permafrost that started just a meter below the surface had suffered incalculable stresses in the 1908 impact. That was almost a century ago, but who could say if the oddly fragile stuff was fully healed even now? Better safe than sorry, especially when burdening the treacherous substrate with the weight of a helicopter under load.
One major component of that load was strapped down right beside Jack. He directed a look of mixed affection and chagrin over at his inseparable traveling companion: a bulky black hardshell equipment case marked Fragile and Property of U. Texas, Austin. It was resting innocuously on the floorboards for now, but, soon as the rotors spun to a stop, the fun of moving it would begin all over again. Not a prospect Jack relished: The thing had to be half the size of his desk back at the Austin physics lab, with a mass nearly the equal of his own hundred eighty-five pounds.
Hauling this monster across thirteen time zones to the remotest spot on earth had taxed Jack’s strength and endurance near the limit. And he hadn’t had all that much to start with. Tall and stringy and slightly stooped, he was not what you’d call an imposing physical specimen. That shouldn’t have mattered much: theoretical physics was supposed to be one of those inside jobs with no heavy lifting. Not this time.
With a grudging assist from the pilot, Jack manhandled the unwieldy case out of the hatch and eased it down to the ground alongside the rest of his luggage. He clamped his trademark ten-gallon hat tight down on his head against the downdraft as the chopper lifted off for the return trip to Vanavara.
And left Jack all alone. He looked around, then down at the case. Was he supposed to lug the thing into camp by himself, in this heat? He couldn’t leave it sitting here, that’s for sure. Without the SQUID, the half-million-dollar instrument nestled safe inside the hardshell, there’d be no hope whatsoever of proving the far-out theories of one Dr. John C. Adler, mad cosmologist. With it ... Well, let the Doubting Thomases beware!
Speaking of Doubting Thomases, Jack’s heart sank as he spied the one-man reception committee now emerging from the main lodge and lumbering toward him through clouds of gnats. Jack recognized that burly giant from the snapshots plastered all over the Tomsk University website: the organizer of this year’s expedition, the man who’d done his level best to block Jack’s participation in it — Academician Medvedev himself.
The man’s name, Jack recalled, came from medved — Russian for ‘bear.’ It sure fit. Professor of Planetology and Member of the Russian Academy of Sciences Dmitri Pavlovich Medvedev bulked tall and broad, barrel-chested and big-bellied in a way that bespoke muscle rather than flab. An unruly black mane threaded with gray reached almost to his shoulders, a match for the scraggly beard, mustache, and brows that framed his sneering mouth, bulbous nose, and glittering black eyes.
“Academician Medvedev,” Jack held out his hand and launched into standard Russian first-contact protocol: “Ochen’ priyatno. Very pleased to meet you. I am —”
“I know who you are, Adler.” Medvedev brushed aside the niceties, along with the handshake. “And I wish I could say I were pleased to meet you. But, frankly, the only thing that would please me would be for you to return where you came from. Better yet, for you never to have come here at all.”
“I can understand your reservations about my research program, Professor, but I —”
“Research program?” Medvedev’s face reddened alarmingly. “What research program? You, you eat our food, drink our water, consume our fuel, occupy space that might instead have gone to a scientist” — he did not quite say a real scientist, though that was what his tone implied — “a scientist with at least some prospect of advancing our knowledge of the Tunguska phenomenon. Instead, what have your American dollars bought you? The privilege of wasting our expedition’s time and resources on your —”
The Russian waved his outsized hands in the air, momentarily at a loss for words to describe the enormity of it all, then exploded: “— your discredited fantasies!”
“Black holes aren’t fantasies, Professor. If theory alone doesn’t convince you they exist, the evidence from the Hubble galactic survey certainly should.” Ever since the late nineties, the earth-orbiting Hubble telescope had been beaming back images of gargantuan black holes infesting the hearts of nearby galaxies. Infesting them and slowly swallowing them whole.
“Bah!” Medvedev’s arm slashed the air so ferociously Jack could feel the wind of it on his face. “No one doubts such monstrosities are real. But how could one of these have impacted the earth without utterly destroying it, and the rest of the solar system, too?”
Jack sighed. “Black holes can come in all sizes, Professor.”
“Yes, yes,” Medvedev broke in again, “You will have an entire week in which to recount these fever dreams to any who will listen. I, for one, will not stand here being eaten alive by these infernal insects while you prattle on!”
And with that, he turned on his heel and stomped off in the direction of the camp, leaving Jack alone with the SQUID once more.
“Déjà vu all over again.” Yogi Berra’s immortal one-liner drifted through Marianna Bonaventure’s head as Compliance chauffeured her down John Street in the direction of the South Street Seaport. The same street where, less than eighteen hours ago, her quarry had ... No, she’d promised herself she wasn’t going to get into that.
The cafes and storefronts lining the narrow street seemed subtly different today: sharper, realer, more fully dimensional somehow. Was that a trick of the clear mid-morning light, or just the way things always looked when you weren’t focused on the chase to the exclusion of all else? Not that this present operation wasn’t a pursuit, too, of sorts.
The Secure Terminal Unit beeped twice. Marianna was already reaching to jack in her headset when she remembered she wasn’t wearing one. Whole different look for this op: Body armor, adieu. Business casuals were lots more comfortable.
“Bonaventure,” she said into the handset.
“Marianna? Pete. Listen, I’ve been thinking ...” Uh-oh! She could feel her boss beaming his heavy-jowled frown at her all the way from Chantilly VA. Pete was having second thoughts.
“Relax,” she told him, “we’re good to go. I’m moving to acquire as we speak.”
“It’s too tight on time, is what worries me. We don’t even know if Bondarenko will take the bait.”
“Already covered. As far as Sasha knows, he’s been in contact with the Archon resource for the past three days.”
“He’s what? You know damn well you can’t involve a civilian without authorization!”
“Take it easy, Pete. It’s done, okay? And it worked.”
“Marianna —”
“Look, we wouldn’t have had time to set up the email spoof if we’d waited till we’d lost Galina first.” Slow down, inhale. “We’ve only got the one shot at this, what with the gala being tomorrow night. We had to have all our ducks in a row before Rusalka sailed. You get that, don’t you, Pete?”
Pete wasn’t saying anything. Not a good sign.
“I knew you wouldn’t buy into it,” she went on, “so I just went ahead and did it. You’ll see — this is all going to pan out.”
The silence on the other end of the secure line was growing uncomfortably long. Pete could still pull the plug, and she couldn’t buck a direct order. C’mon, Pete, think it through. It’s not like you wouldn’t have green-lighted the Hail-Mary eventually — you’d have just been too late.
“Okay,” he said at last, “Make it work.”
“Pete, you won’t regret it.”
She hoped.
“Dio mio, Jack, my arm hurts still!” Dottore Luciano Carbone slumped down by the campfire and rubbed his shoulder demonstratively. “That box of yours must weigh a ton. Why in God’s name did Medvedev make us drag it all the way out to choum seventeen?”
“Why do you think, Luciano?” Jack Adler grinned at the tubby, balding University of Bologna geologist — the only friend he’d made in his first half-day on site. A friend in need, too. If the little Italian hadn’t lent a hand, it would have taken all night to get up and running. Even so, it was well past the dinner-hour before they tramped back in, sweaty and exhausted, from what had to be the remotest choum, or birchbark tepee, in the camp.
The Italian stroked the black curls of his goatee. “That man does not like you so much, is what I think — to put you so far away.”
Jack chuckled. “I’m not exactly his favorite guest researcher, am I? But there’s a simpler explanation for sticking me out in the boonies. Hear it?”
He cupped a hand to his ear. Sure enough, the faint chuff-chuff-chuff of his diesel-powered compressor was audible even at this distance.
“That unit’s going to be cycling on and off day and night just keeping the SQUID cold enough to operate,” Jack said, “And getting a good night’s sleep out here isn’t all that easy as it is, what with the skeeters and such. No sense my adding noise pollution to the problem.”
Luciano opened his mouth to respond. A cough came out instead. Understandable, since he was directly downwind of the smoky fire. At first Jack had wondered why they were sitting around the campfire at all. It sure wasn’t for warmth — Siberian summers might be short but they made up for it with extra helpings of heat and humidity. Turned out, though, that the woodsmoke kept the ravenous Siberian mosquitoes — “flying alligators,” the Russians called them — at bay. It was the one deterrent that worked. Conventional bug-spray only served to encourage the insects.
“Sorry, Jack, sorry,” — cough, cough — “what I wanted to say: perhaps the real reason our esteemed Academician has isolated you from the rest of the party is for fear of infection.”
“Quarantining my contagious ideas, eh?” Jack smiled again. He liked this rotund, genial little man with his cherubic face and sly Machiavellian wit. “Don’t worry, Luciano — from what I can tell, my ‘discredited fantasies’ aren’t catching.”
“Because you do not trouble to explain them.” Luciano stifled another cough. “Your theories, I mean, not your fantasies. I have read the abstract of your research proposal twice, but I confess this business about the very little black holes still remains a mystery to me.”
“Didn’t seem much point going into detail, seeing how our friends from Tomsk were going to take the money and run, regardless.” As the premier center for studies of the Tunguska phenomenon and the host institution for the expedition, Tomsk University had final say on what research might be conducted at the site.
Jack swiped at the air with his Stetson, beating back another insectile assault wave. “— And close their ears to what I had to say in the process,” he added.
“Not all of them perhaps.” Luciano flicked his eyes off to Jack’s left.
Jack turned to see a young blond Russian standing five feet away, listening to them. And looking at the Stetson. What was the real attraction here: Jack’s theories or his cowboy hat?
Caught eavesdropping, the young man blushed and pushed thick bifocals back up his nose. “Excuse, please. — Zaleskii, Igor Andreyevich, aspirant in molecular biology at Tomsk University. I could not help but to overhear ...”
“No harm done.” Jack said. “Sit down, Igor, pull up a stump and join the party.”
The newcomer gave a grateful nod and joined them at the fire. He squatted down, looked both ways, then reached into his hip pocket and pulled out a metal flask. “Russian mosquito repellent,” he said, handing it to Jack with a grin. “For internal use only.”
Jack unscrewed the lid and took a sniff. Vodka — what a surprise. He glanced at his watch: If he’d managed to keep pace with all the time-zone changes, it was past ten in the evening. At any reasonable latitude, the sun would’ve been over the yardarm hours ago. Even here the sky was beginning to stain with sunset. Close enough.
“Thanks.” He took a swig and passed the flask back to Igor. “So, what’s a biology grad student doing on this junket?”
“I assist Professor Nakoryakova with her studies of trace radioactive isotopes in local soils and flora.” Igor sipped at the flask and handed it to Luciano. “Other than the physical evidence of treefall and the like, residual radiation is the most persistent signature of the Tunguska Event. — But please, I did not wish to interrupt. I, too, am interested in what you say about your little black holes. Are they very different from the big ones?”
Jack shrugged. “Depends. What do you know about the big ones?”
It was Luciano who finally replied. “They are said to form when a star grows so heavy that it collapses under its own weight.”
“That’s good, but it’s not the whole story. Maybe it’s better if we back up a bit, begin at the beginning. And, for a black hole, the beginning is gravity.”
Jack downed another slug from the passing flask. The vodka did seem to be keeping the mosquitoes at bay. Or maybe he was just noticing them less.
“The thing of it is,” he went on, “Gravity’s just not very powerful, as forces of nature go. Compared to the strong nuclear force, it’s the next best thing to nonexistent. Even plain old electromagnetism’s got it beat hands down. You ever pick up a three-penny nail with a toy magnet? Then you know how even a teensy bit of electromagnetic force can overcome the gravitational pull of the whole earth.”
Jack shook his head. “When you get right down to it, the only thing gravity’s got going for it is, it just keeps on adding up.”
“But is this not true of the other forces as well?” Luciano asked.
“Not really. The nuclear forces are too short-range to amount to much over the long run. Electromagnetism’s got the reach, all right, but it comes in opposing flavors: positive and negative charges, north and south poles. That puts a natural upper limit on how strong an electromagnetic field can get before it attracts enough opposite charges to neutralize itself.”
“And gravity, you are saying, only works one way?”
“Uh-huh. Never lets go, never cancels out. That’s unique for a long-range force, and ultimately it’s decisive. Pack enough mass into one place — like in a planet ten times the size of Jupiter — and the field-strength at the core exceeds anything electromagnetism can stand up to. The electron shells that give things their structural strength, why, they just up and buckle. What started out as nice, solid matter — like this,” Jack rapped his knuckles on the log he was sitting on, “dissolves into a soup of dissociated electrons and free nuclei.”
“And so this is how you make black holes?” Igor said.
“Not quite. No, what I just described —” Jack pointed up through the branches to where the first faint pinpricks of light were just beginning to appear in the darkening sky, “— is how you make stars.”
Knox had been at his desk and sitting on his hands half the morning, waiting for normal business hours — or Mycroft’s peculiar definition of them — to begin.
The country of the night is the coder’s true homeland, and Mycroft, a loyal native son. In the fresh, clean hours after midnight, with the petty interruptions and annoyances of the day fading like dreams at dawn, he essayed prodigies of system design, assembling soaring fairytale architectures of logic, elegance, and power from the dry dust of global variables and reserved keywords. But it did make him a devout late sleeper.
Knox flicked his gaze to the timestamp in the corner of his widescreen: Ten twenty-five. Give it another five minutes.
His speakerphone emitted a muted chirp.
“Mycroft?” Calling in early? That would be a first.
“Front desk,” the voice of Archon Office Manager Suzanne Ledbetter corrected. “Were you expecting a visitor, Jon?”
“Unh-uh. My calendar’s clear far as I know.”
“Well, you’ve got one — take a look.”
A small conferencing window popped up on Knox’s screen, offering a realtime view of a young woman in casual dress. She was standing at the reception desk, communing with her wristtop. Knox zoomed the window to full-screen mode. Did he know her? She didn’t look like someone he would soon forget. She looked ... striking, the way that dark hair complemented her ivory complexion.
“I don’t know her,” he said finally. “Not that I wouldn’t like to. Did she say what she wants?”
“What who wants, Jonathan?” A second voice broke in, issuing from the new conferencing window now staking out its own piece of screen real-estate.
“Oh, good morning, Mycroft.”
Knox didn’t need to ask how the night’s researches had gone. If Mycroft’s sly grin weren’t enough, his computer-enhanced imagery — the black eyepatch and rakish red bandana, the Jolly Roger fluttering against a backdrop of sky and sea — all betokened a successful hack.
“Jon?” Suzanne again. “What should I tell her?”
Oh, right — his unscheduled visitor. “Uh, I could be tied up with this for a while. See if she wants to hang out, or maybe come back after lunch, okay?”
“Okay.” The reception window irised shut.
Knox turned back to Mycroft. “Took you long enough.”
“I trust you will find it well worth the wait, Jonathan.”
“The wait got old an hour ago.”
“Yes, well, I’m afraid it must get a little older. There are a few preliminaries to cover first.”
“Can ’em.” Knox pulled his chair in and leaned forward. “Get to the good stuff.”
Half a world away, Jack Adler was getting to some good stuff of his own. He peered through the smoke of the campfire at the expectant faces of his listeners, thinking how best to put it across.
“Stars are really just controlled gravitational implosions,” he began. “Take that super-Jupiter we were talking about. Once gravity overcomes its structural integrity, it starts to shrink. It’d go right on shrinking, too, except compression generates heat, and enough compression’ll heat the planet’s core to upwards of ten million degrees Kelvin. That’s the flashpoint: At that temperature, the free atomic nuclei are moving fast enough to start slamming into each other. The strong nuclear force takes over and thermonuclear fusion kicks in.”
No matter how many times Jack told this story, he was always struck anew by the wonder of it. “Fusing hydrogen into helium releases energy. Colossal amounts of energy. Enough energy to push back against the pull of gravity. Enough to light the heavens. Enough to warm the worlds and spark the chemical processes that lead to life, to us.
“Enough to make stars,” he breathed. He paused again, looking up. This sense of awe was as close as he got to what, he supposed, other people felt in the presence of the sacred.
A hush fell over the little group. No sound stirred the still, warm evening air, save for an occasional pop from the fire.
Jack shook himself. “Of course, things can’t go on like that forever. It takes fuel to keep those fires burning — hydrogen, in particular. The average star holds enough to chug along for billions of years, converting hydrogen to helium. But sooner or later it’s got to run out. And, when it does, the squeeze starts all over again.”
Once it resumed, gravitational contraction would raise the core temperature back up to where the fire rekindled. Only now the helium ‘ash’ itself became the fuel, fusing into heavier and heavier elements — carbon, lithium, oxygen, neon, silicon, finally bottoming out with iron. Then, nucleosynthesis having reached the point of diminishing returns, the stage was set for the final act.
“At the very end there —” Jack was staring into the campfire, seeing instead the cataclysmic last moments of dying suns, “— gravity can grip hard enough that the core of the star just ... collapses. Collapses so fast, it rebounds. You get a gigantic explosion, a nova or supernova. The star puts out more energy in that single instant than it did in a lifetime of steady shining. The shockwave is powerful enough to transmute elements wholesale.” In its spectacular death throes the star would seed the universe with the building blocks of new worlds, new life.
“In the aftermath,” he went on, “the key thing is how much of the star’s original mass the explosion leaves behind. If it’s only around a sun’s worth, no problem: Atomic nuclei have got more than enough structural strength to hold up under that much weight. You wind up with a brown dwarf star the size of the earth.
“But go upwards of that, and things start to get interesting.”
Jack looked up. Three more expedition members, two middle-aged men and a younger woman, had come trooping in from the twilight forest and were walking purposefully toward the firepit. They gave Jack a perfunctory nod but continued talking quietly among themselves. Not here for the soapbox seminar, then — just more refugees from the gnats.
“Please go on, Jack,” Luciano said. “You were saying?”
“Oh, right. Well, if the leftovers weigh much more than the sun, things start to happen: The pressure in the interior of the ‘cinder’ is enough to mash electrons and protons together, so you get neutrons. That triggers another collapse, into a neutron star only a few miles across. Bizarre enough in its own way, I suppose. But the point where us relativity theorists really sit up and take notice is when the supernova remnant is more than three times the mass of the sun. Not even neutrons can hold back that much gravity; they just up and cave. And neutrons are the last line of defense. Once they go, the whole mass collapses to what we call a singularity — a dimensionless point of infinite density, infinite space-time curvature, infinite you-name-it.”
“Now you go too far, Adler,” a rumbling bass broke in.
Jack turned and saw Medvedev’s great bulk looming just beyond the circle of firelight. “Oh, good evening, Academician,” he said. “I didn’t see you standing there. I’m sorry, what did you mean, go too far?”
Medvedev sighed in seeming exasperation. “As everyone knows, the infinite is purely a mathematical construct. It can exist nowhere in nature.”
“Maybe not for material objects and such. But gravity’s different. When you get right down to it, gravity is mathematics — geometry to be exact.”
Medvedev said nothing, just stood there glaring at him.
“Look,” Jack went on, “imagine that our three-dimensional space is a two-dimensional sheet of rubber. Then gravity’d just be a measure of how much that rubber sheet stretches when you drop a mass on it — a little for a marble, a lot more for a bowling ball. Drop a planet-sized mass onto that rubber sheet and the nearby surface’ll dip down to form a gravity well, one so steep it can curve the path of a moon into orbit around it. Drop in a sun, and you’ve got a deformation deep enough to trap a whole family of planets.”
“This much I grant you,” Medvedev said. “Still, I hear in it nothing of your supposed infinities.”
Jack held up a hand. “Hang on, I’m getting there. Turns out when a really massive star dies, it can form a sink-hole so deep that the well-walls wrap around and pinch shut, sealing off its remains from the rest of space-time. Remember Alice in Wonderland, where the Cheshire Cat vanishes, leaving only its smile behind? Well, here, all the matter disappears, collapses to a point, and only the mass is left. Enormous mass, taking up zero room. I don’t know about you, but that sure sounds like infinite density to me.”
Jack glanced at Medvedev, but the big Russian was back to holding his peace, at least for the moment. That was okay; it would only take a moment to finish this up.
“If there are no further questions,” Jack said, “then there’s only one more thing to add. Namely, that while all this is going on, the gravity gradient is getting steeper and steeper. Until it’s finally so steep that nothing, not even light, can escape ...
“ Which is why we call them black holes.”
“Very nice, Adler.” Medvedev was smiling through his beard now. “A pretty story, but it has been told before. Two hundred years ago, the Frenchman LaPlace imagined ‘black stars’ with escape velocity greater than the speed of light. Why not be so good as to share with us the fruits of your own intellect instead.”
“Well, these aren’t really my ideas, you understand,” Jack said. “But the fact is, supernovas aren’t the only way to make black holes. Every mass has its own cosmic point of no return — a lower limit on its size called the Schwarzschild radius. Beyond that, gravity takes over and collapses it down to a singularity. Shrink any mass small enough, and you get a black hole.”
Medvedev smirked. “Even, perhaps, this?” He bent over abruptly. When he straightened again he was holding out a small lump of river-rounded rock.
“Huh? Yeah, sure,” Jack said, eyeing the pebble. “Though it’d be easier to visualize if we start with something slightly larger. The earth, say.”
“By all means, choose what example you will.” The Russian eased himself down opposite Jack, keeping the fire between them.
“Okay, well, earth’s Schwarzschild radius is about one and a half centimeters. So, if you could put the whole planet into some humungous vise and crush it down to a one-inch sphere, it would become a miniature black hole.” Jack looked Medvedev in the eye. “With me so far? This is all just plain-vanilla relativity.”
“No one disputes what you say, in theory,” Medvedev bristled, “But where is the actuality? Show me this fantastic vise, this ‘Schwarzschild machine’ of yours. Let me create a singularity myself, purely as an experiment. Then I, too, will believe.”
“You know that’s impossible. The pressures needed are unimaginable, beyond anything we can even dream of today.”
“Hah!” The Russian turned to his colleagues with a told-you-so grin.
Jack sighed. “But that doesn’t mean it’s never been possible. There was more than enough radiation pressure in the first instants of the Big Bang to spawn PBHs — primordial black holes — of arbitrarily small size. And, as you know ...”
“Yes, yes,” Medvedev said, “I know only too well: It must therefore have been one of your famous PBHs that caused the Tunguska Event. All the generations of scientists who have struggled to understand this phenomenon of the Tunguska Cosmic Body are fools, fools or worse — futilely scouring the taiga for a meteorite that never existed. So claim the Three Wise Men from Texas University: Jackson and Ryan and Adler.
“But, Adler,” Medvedev went on, “I say it is you who are the fool, coming all this way in pursuit of what was known to be folly when first published thirty years ago.”
“Known? What do you mean known?”
“Simply that if your compatriots Jackson and Ryan had troubled to acquaint themselves with the geophysical evidence — evidence gathered painstakingly over the years by serious researchers — they would never have put forward their preposterous idea in the first place.”
“Believe me when I tell you,” Jack said, “that I’ve gone back and forth over your geophysical evidence, what little there is of it: Seventy years of expeditions, and you still haven’t got a clue what the thing was. Was it a comet? A meteor?” He shook his upraised hands in mock dismay. “We don’t know, we can’t tell. Let’s just call it a TCB, a ‘Tunguska Cosmic Body,’ and have done with it.”
A frown crossed the Russian’s broad features. “But this is standard scientific nomenclature —”
“Face it, Medvedev: calling the thing a TCB is an admission of defeat. It says you don’t know what you’re talking about, that your so-called ‘evidence’ is full of holes, inconclusive in the extreme. Except, of course, in those instances where it actually lends support to the Jackson-Ryan hypothesis.”
“Support?” Medvedev snorted. “To what support do you refer?”
“Well, take the geomagnetic storm that Irkutsk Observatory tracked for hours following the impact. That effect could easily be accounted for by the right type of primordial black hole. At the same time, it just about rules out your own candidate for the Tunguska Cosmic Body. You guys from Tomsk have been pushing the TCB-as-comet theory for as long as anyone can remember. But comets aren’t magnetic — they’re mostly made of ice.”
“A meteorite after all, then,” Igor put in, to Medvedev’s evident displeasure.
Jack turned to him. “Okay. Only now you’re stuck explaining away another key piece of geophysical evidence: no crater. By Medvedev’s own calculations, his TCB would’ve been the biggest thing to hit earth in fifty thousand years. And base camp here can’t be more than a mile or so from the epicenter. So why aren’t we sitting at the bottom of a hole the size of the Grand Canyon?”
“As is well known,” Medvedev said stiffly, “the lack of a crater is due to the event having been an airburst.”
“An explosion kilometers up, resulting in complete volatilization of a meteoric body?” Jack said, “Sorry, I don’t buy it. All right, maybe, if it was a stony meteorite. But you need a ferrous meteorite to explain the magnetism, and there’s just no way that much iron could totally self-destruct.”
He shook his head. “No, when you add it all up, the airburst theory begins to look like just another circular argument: The strongest support for it is the thing it’s supposed to be explaining: ‘No crater? Okay, then, must have been an airburst!’ Call that evidence? — Give me a break!”
“I see no reason why we must sit here and listen to this, this —” Medvedev began.
But Jack wasn’t done yet, he’d saved the best for last. “— And let’s not forget who started this whole airburst business. One of Kazantsev’s crackpot theories, wasn’t it? That’s some strange company you’re keeping, Academician.”
No one spoke. The only sound was the crackling of the campfire. Igor sucked in his breath but said nothing. Luciano choked on a laugh and covered his mouth with his hand. Medvedev glowered, his eyes far redder than could be accounted for by the pungent woodsmoke.
To so much as mention the mountebank Kazantsev in the same breath as the revered Academician was nothing short of scandalous. For it was Aleksandr Kazantsev who, fresh back from a 1946 inspection tour of the Hiroshima devastation, had startled the world with the claim that the 1908 Tunguska catastrophe had resulted from a similar high-altitude nuclear explosion — the explosion, in fact, of a nuclear-powered spaceship from Mars!
Medvedev had lurched to his feet now, and was standing there hunched over, still not speaking. The firelight cast his distorted shadow huge against the wall of Kulik’s old cabin. In its eerie glow he bore the look — eyes widened, teeth bared — of a beast baited almost beyond endurance.
Jack wasn’t about to back down. “Take your pick. Whichever hypothesis you choose, there’s always some piece of your ‘geophysical evidence’ guaranteed to undermine it.”
For a moment Jack thought the Russian was going leap the firepit and attack him physically.
Instead, in a voice shaking with barely-checked rage, Medvedev bellowed: “Yes? Well here is a piece of geophysical evidence I invite you to explain, Adler: Your lack of a so-called ‘exit event.’” He drew a deep breath. “If your ridiculous theory were true and the TCB were in truth one of your micro-holes, nothing could have prevented it from boring down through the earth and out the other side, true? Your friends Jackson and Ryan said as much, predicting that it would come rocketing up out of the North Atlantic shortly after its touch-down here. Their 1973 Nature article, in fact, offers this retrodiction as a test of the whole hypothesis.”
“Aha! So you have read it then.”
“Oh, do not look so surprised, Adler. Of course I have read it. I enjoy science fiction as much as the next fellow.” Medvedev smiled tightly. “But, here is my point. If your ‘micro-hole’ could cause such devastation on landing here in Tunguska, how could it not do so again on erupting up out of the ocean on the other side of the world?”
“Well ...” Jack began.
But there was no stopping Medvedev now. “It should, in fact, have raised a catastrophic tsunami, not so? Vessels in the Atlantic shipping lanes should have been capsized by the shockwave. A wall of water fifty feet high should have gone crashing against the shores of Iceland and Eastern Canada — areas far more densely populated than Central Siberia, then as now. Why then do the newspapers of the time contain no reports of such a disaster?”
The Russian leaned closer, teeth bared in an unpleasant grin. “I will tell you why, Adler. Because it never happened! None of it did. To think otherwise is the worst sort of naivete and scientific irresponsibility!”
All eyes were now on Jack, waiting to see how he would respond.
Jack chose his next words carefully. “Remember your Sherlock Holmes? The one where he says ‘Once you’ve eliminated the impossible, whatever remains, however improbable ...’”
“‘Must be truth,’” Medvedev finished for him, “Yes, yes, this is well known. But what is your point?”
“Just this,” Jack said in a low voice, “I don’t think the thing ever came back out.
“I think it’s still in there.”