The Lure

6 Patterns

Having just sat down, Gibson jumped up again. ‘Follow me.’

He led the way round the bend of the left-hand corridor. At its end was an ornate door. He waved them dramatically through it.

The room was about fifty metres long. On its high barrelled roof was a fresco of cherubim. The little creatures were on a hillside, reading maps or turning hour-glasses. One, its wings an aerodynamic impossibility, was flying through a star-spangled sky, holding a pennant bearing the words Sapientissimi Opus. The room was lined with books on either side and antique globes were scattered around.

‘This is the theological library, folks. Take a look at this.’ A single strip of perforated paper was laid along the full length of its polished floor and back up the other side. The numbers were upside down and the scientists bent double over them, walking slowly backwards.

‘There’s this big cave complex a few hours north of here, see? It has a deep lake half a mile across and we’ve built an aluminium scaffolding under it to hold light detectors. We have fifty thousand photocells, laid out in a cubic lattice. The numbers in the left column go from one to fifty thousand. They’re just labels. The next column records light intensity picked up from each detector. As you see, there’s nothing but zeros.’

‘I’m not surprised,’ Petrie said, moving backwards. ‘How can you expect to record underwater light in a pitch black cave?’

Freya said, ‘GUTS decay has been ruled out for ten years now. You have to be talking Çerenkov.’

Gibson gave her a look of open admiration. ‘Ten out of ten. Funny things happen when you go faster than light. Çerenkov radiation is one of them.’

‘I thought you couldn’t travel faster than light,’ Petrie said.

‘Only schoolboys think that,’ Gibson said smugly.

Petrie bristled, then decided the man was too absurd to be taken seriously. ‘Thank you, Charlie, for treating me like an idiot.’

‘Light moves slower in water,’ Freya explained. ‘In principle you could swim through water faster than the local light speed. If you did, you’d leave a trail like a sonic boom, only with light rather than sound. That’s Çerenkov radiation.’

Gibson said, ‘Fortunately you’re not here for your physics.’

Petrie resisted the urge to punch the arrogant toad on the nose. ‘Why am I here?’

‘Patience.’

‘I’ve always thought of Çerenkov radiation as faint,’ Freya said, scanning the numbers.

‘To the eye, yes. The retina needs sustained light for about a fiftieth of a second before it records anything. But our detectors have quantum efficiencies pushing a hundred per cent; they can track a single photon. Which is one good reason, incidentally, for being deep under the ground.’

‘Okay.’ Petrie was scanning the figures impatiently. ‘So a particle tracks through the water and you pick up its trajectory from the trail of light.’

‘We time it to a ten-millionth of a second — about the time it takes a particle to cross the lake top to bottom. That’s the numbers in the third column. Now come over here.’ A table, which in the eighteenth and nineteenth centuries had presumably hosted dinners for thirty or forty, was now covered by more computer printout, three inches deep, laid out along its forty feet. Petrie saw an incomprehensible mass of numbers. He moved along the table, flicking through the lists. ‘Hey!’

Gibson nodded. ‘Yes. No more lists of zeros. This is a single particle track, a cosmic ray. It’s moving through the water at superluminal speed, so it leaves a Çerenkov trail.’

‘It penetrated how far?’ Freya’s voice registered incredulity.

‘One point seven kilometres of limestone karst.’

‘Hold on. You’re under a mountain.’

‘Yes. Most cosmic rays are stopped by a metre or two of ground. Watch that chair.’

‘That’s awesome,’ she said lamely.

‘And it had the kinetic energy of a fast cricket ball. What sort of hell’s kitchen it must have escaped from I can’t begin to imagine. But that’s not why you’re here. No, folks, that’s not even remotely why you’re here. We can backtrack the trajectory, sort of. This particular particle seems to have come in a straight line from a galaxy called M104, about fifty million light years away.’

‘The Sombrero, I know it,’ Freya said, as if she’d vacationed there.

Petrie was still scanning the columns. ‘So this particle had been travelling for fifty million years before it zipped through your lake?’

‘Yes, but like I say that’s not why you’re here. By no means.’

Some Austrian prince, all haughtiness and whiskers, was glaring down at them from the panelled wall. Petrie continued, ‘No doubt you’ll get round to telling us.’

‘We’re trying to solve the dark matter problem.’

‘What’s that?’

‘Groan,’ Gibson said. ‘Nothing special, just the biggest mystery in the Universe, that’s all. Okay, let me do this in words of one syllable. We can weigh galaxies from their mutual orbits, knowing the strength of gravity. They turn out to be ten times more massive than we’d expect from their luminosities. That is, a typical galaxy has ten times more mass than the sum of all its stars. That’s a big discrepancy.’

‘You mean, out there, gravity’s stronger than you think?’

Gibson looked as if he was fighting a sudden pain.

Freya laughed. ‘You shouldn’t say things like that, Tom.’

‘Why not?’

‘It’s heresy. The law of gravity is sacred.’

‘So what’s the party line?’

Gibson said, ‘The solution is obvious. There must be a lot of dark matter inside galaxies. It has gravity but it doesn’t shine.’

‘The problem’s much worse than Charlie is telling you,’ Freya volunteered. ‘When you get to big clusters of galaxies, say hundreds or thousands of them, you find that they’re flying around at speeds vastly in excess of what’s expected from their visible mass. Something invisible is stopping these clusters from flying apart.’

‘How do you measure their speeds? You don’t see them moving?’

‘No, but their light is shifted to the red or blue pro rata with their velocities, like the change in pitch of a train whistle when it passes. You find that the dark stuff in clusters has to be about ninety-five per cent of the total mass. What we’re saying here is that the whole of astronomical science is devoted to only five per cent of what’s out there.’

‘Right. So rather than change the law of gravity, which is sacred, you assume that there’s some exotic new type of particle. Invisible but with mass. If you find it, you have a handle on the missing ninety-five per cent of the Universe.’

‘On the nail,’ Gibson said. ‘A subnuclear particle unknown to present-day science. There could be millions of them passing through our bodies now.’ Gibson’s froglike face had acquired a fanatical look.

‘Where are these particles supposed to come from?’

‘Hell, Tom, they were created in the Big Bang. They must have been.’

‘Yes, all right, Charlie, I believe it. In fact, I believe everything you’re telling me.’

Freya asked, ‘Okay, Charlie, but why in the hinterlands? Why not someplace civilised like the Alps?’

‘The Alps have been taken: a rival team got into the Mont Blanc tunnel long before us. Likewise the Gran Sasso in the Italian Apennines. And the karst limestone here-abouts has very little natural radioactivity. Anyway, our technique needs an underground lake. It’s worth a little sojourn in the Carpathian hinterlands to solve one of the greatest scientific mysteries of the age.’

‘And pick up a Nobel Prize in passing.’

‘Provided we beat the competition.’

‘You just did,’ said Freya.

Gibson said, cryptically, ‘Except that we got more than we bargained for. Follow me again.’

Gibson marched out of the library, half-ran back along the corridor and up broad stairs. He turned left and stopped at an oak door, puffing slightly.

He paused, his hand on its large wooden knob, and blinked. ‘The stuff on the other side of this door will change your life. This is your last chance to walk away.’

‘My goodness, Charlie, this is dramatic stuff.’ Petrie’s tone was light, but he was tense with excitement.

‘Okay — you had your chance. Welcome to Wonderland.’

Gibson opened the door.

Petrie stared into a large room, almost bare apart from a square central table around which were half a dozen chairs embroidered with some royal insignia. On the table were six computer terminals. Windows on the right opened out to a snowy wooded landscape. At the far end of the room, wood panelling had been slid aside to expose a bank of television screens. Two people were standing at a screen, obscuring it. They turned, and Petrie formed instant impressions.

There was Miss Dominatrix. A long-haired female, midthirties, spinsterish, with a long thin face and an intense, dedicated look. She was dressed in black sweater and slacks, and fashionless trainers. She was devoid of makeup but wore sapphire earrings.

Gibson made the introductions. ‘Well, at last we have our mathematician, Thomas Petrie, and our astronomer, Freya Størmer. The team’s complete. Tom and Freya, this is Vashislav Shtyrkov and Svetlana Popov.’

Svetlana alias Miss Dominatrix had an unexpectedly warm smile. ‘Cracow University, Poland. I just join up the wires.’

‘Svetlana’s modesty is out of place,’ Gibson said. ‘She’s a first-class experimentalist.’

The two women were shaking hands. ‘I know, Charlie, I just like to hear you say it. You must wonder what you’re getting into, Freya.’

‘It’s all very clandestine. I think Tom and I are in the hands of paranoid lunatics.’

Shtyrkov approached and extended a powerful hand to Petrie. He had a deep bass voice, with a slightly breathless edge. ‘Moscow State University. I do particle physics. Freya is right, I’m a paranoid lunatic. As will you be after a day or two here. So, you’re our Irlandets?’

‘Anglichanin,’ Petrie corrected him. He turned to Gibson expectantly.

Gibson beckoned Petrie over to the terminals on the wall and pointed to the one on the left. ‘What do you make of this?’

Petrie and Freya sat down on Hapsburg embroidered chairs and found themselves staring at an array of numbers, arranged into three columns. Petrie pressed the ‘down’ arrow on the keyboard and scanned the rapidly tumbling columns, his eyes trying to make out patterns.

The patterns were there. As the columns skimmed past, the numbers rose and descended in waves, some large, some small, some fast, some slow. They interacted like Bach fugues, sometimes merging into breakers, sometimes abruptly turning into columns of zeros.

Shtyrkov was looking over Petrie’s shoulder. ‘You saw the printout in the hall?’

‘Uhuh. This is a lot more complicated. It must be more than one particle, which is impossible from what Charlie was saying. There must have been dozens of them.’

‘Not dozens, Tom. Billions.’

Petrie stopped scanning. He looked at Gibson.

Svetlana was lounging back at a desk, playing with a pencil. ‘At any instant each litre of water in that lake had a particle in it.’

Petrie turned back to the terminal and resumed the scan. ‘But if a particle crosses the lake in a ten-millionth of a second … how long did this go on?’

Gibson spoke over Petrie’s other shoulder. ‘Thirty-seven minutes. There were about half a dozen leaders. They arrived every few seconds. Then it started. Two thousand, two hundred and twenty seconds of this, and then it stopped. No tail-off or fading away: there was just suddenly nothing.’

‘The lake glowed.’ Shtyrkov’s eyes had a strange, almost insane gleam.

Freya turned to Gibson. ‘Just what are we dealing with here?’

There was a brittle silence.

Petrie sensed something. ‘So each detector was picking up light from all the particles passing through, and you have fifty thousand detectors each firing numbers into your hard drive ten million times a second, and you want me to turn these numbers into particle tracks through the lake.’ He puffed out his cheeks. ‘That’s a mammoth job.’

Gibson shook his head. ‘Oh no, Tom, that’s not what we want from you at all.’

Svetlana said, ‘You see, we’ve already done that.’

‘I linked in to Moscow State University,’ Shtyrkov said. ‘It’s the central node for a nationwide grid of computers. I was able to use idle time on every computer in Russia which holds hands with the Moscow link. No, we have computed the particle tracks. And the tracks through the lake are where you come in.’

Petrie looked around, bewildered. ‘If this was a burst of particles from some source, surely they just came in on random parallel lines, like a stream of buckshot?’

Shtyrkov grinned. ‘No again, Tom. Not at all. You see, the particles arrived in a pattern.’

‘What?’

The grin became demonic. ‘Yes, a pattern.’

Petrie felt his skin prickling.