Twistor (15 page)

'Yes, I believe you've mentioned that before,' David said.

Paul realized that he'd probably slipped into lecture mode. 'OK,' he said, 'but here's the new part. I've found a superstring variant that looks very interesting, except that it has a sort of ungainly appendage. It predicts the existence of extra "shadow matter" particles in addition to the normal ones, particles that share the same space-time and the same gravity with normal matter but are completely noninteracting in all other ways. The two kinds, shadow and normal, completely ignore each other except through gravity. There would be two distinct types of light also, with each kind of light interacting only with its own kind of matter.'

'Is that why you call it "shadow matter," ' asked David, 'because only its gravitational shadow could be detected? Invisible matter and even invisible light . . . sounds like H. G. Wells or something. And you think it has something to do with our recent results?'

'Maybe,' said Paul. 'Since yesterday I've been playing with the idea that your twistor apparatus, in rotating the electromagnetic field as it does, somehow precesses all the particles in a certain volume of space, using one of the extra dimensions as a rotation axis, so that normal particles become shadow particles. If that were to happen, the Earth's gravity would still be there, so an object converted to shadow matter should still fall. It's as if the particles are still physically present, but they have been made invisible and noninteracting. Or maybe it's
better
to consider that the matter inside the sphere has been moved to a universe next door – call it a "shadow universe" – where it still feels the pull of Earth's gravity but nothing else.'

'That's wonderful!' said David.
'
It really fits with what we've been seeing.'

'Anything else in the way of new results?' asked Paul.

'As a matter of fact, yes,' said David. 'I once read a Paul Davies book that made a big deal of the delicate balance of the physical constants in our universe that's required for the existence of living things. So Vickie and I decided to see if a living thing could survive a brief exposure to the other side of the twistor transition. Vickie has a friend who's a psychology graduate student, and she lent us a white rat. His name is Neil Tailstrong, the extradimensional astro-rat.'

Paul laughed. Melissa looked interested.

'We put Neil into a sealed jar and dropped him through the twistor transition,' David continued. 'The astro-rat office of mission control is happy to report that both Neil and the launch vehicle came through the transition with no apparent problems.'

'Do you still have him? Could we see him?' asked Melissa.

'He's not at my lab anymore,' David said. 'Neil's returned to his normal place of residence in the psych department's rat lab, where he's being checked periodically to make sure he stays healthy. If he survived his trip to your shadow universe, it can't be immediately hostile to life.'

Paul smiled. 'That's indirect evidence that the forces between shadow particles are the same as for normal particles,' he said. 'That's very nice to know, David.'

Elizabeth looked up from her reading to glance from one of them to the other but didn't say anything.

'The other news item,' David continued, 'is that I didn't have the equipment to try your test with the radioactive
source,
but I did make a small permanent magnet disappear. Since gravity still affects materials after the twist, I was wondering if we could use some kind of magnetic suspension to keep things from falling out of the field during a transition. But it didn't work. I had a Hall probe mounted just outside the field sphere, but near enough to register the magnet's field. As soon as the transition hit, the reading from the Hall probe dropped to zero and stayed there. Magnetic fields don't get through.'

'Great! It's wonderful to make predictions that work,' said Paul with a feeling of rising excitement. 'Now I'll make another prediction. I'll bet you can't make an electrically charged object completely disappear. When you try, most of it will go. But you'll leave behind enough electrons or positively charged ions to make what disappears electrically neutral.'

'Yes,' said David, standing up excitedly and walking over to the window, 'I think maybe I can test that. I could borrow some of the hardware from the Physics 122 lecture demonstration I did last week. The old Wimshurst machine might work nicely.'

'And watch the energy required,' said Paul. 'There may be a small extra energy loss in separating off the charges because of induced fields.'

David looked at his watch. 'Guess I have to be moving along. Vickie and I are meeting Allan at the lab at twelve thirty, and I have to do my laundry first.' He turned to Elizabeth, who sat reading a novel at the other end of the table. 'Ever notice, Elizabeth, how the guys in works of literature never have to worry about doing their laundry?'

She looked up at him. 'Probably the writers have better taste than to mention it,' she said, and smiled.

He grinned back. 'Thanks very much for the breakfast, Elizabeth,' he said. 'I feel like a new man.' He tickled Jeff, got up, and headed for the door.

Elizabeth smiled after him, then turned back to her book.

Paul
sat for a long time, thinking about what David had said. Then several ideas began to take form. He stood and walked toward the stairs. As he moved toward his basement computer link, the symbols of an algebraic manipulation task for the UCSD Cray-4 began to assemble themselves in his head.

Martin Pierce had been in his office in the Megalith Tower for most of Saturday morning, working on a report for the president. He looked up as a beeping sound came from the built-in computer terminal in his broad rosewood desk. Ah, he thought, that's to remind me to check on the progress of the agents in Seattle. He levered the flat display screen into position and logged on, then established a secure link to the PSRS system. The connection was established and the message
User Name:
appeared on the screen. Pierce provided the two passwords, and the usual PSRS header message followed:

Welcome to the PSRS HyperVAX 98000 running under VMS 8.7
.

This is the Puget Sound Reference Service.

Library reference services and literature searches are our specialties.

Pierce made a directory listing of his
[BROADSWORD]
area and found that there was a new file there called
S931008.TXT.
He downloaded the file to his own computer and logged off the PSRS system. Then he decrypted the new file With the prearranged 'DOG' decryption key. The file was a transcript provided by Mandrake of the recordings collected yesterday over the time period from seven P.M. until midnight from the voice and telephone surveillance of Saxon's laboratory and office.

Pierce read the transcript twice carefully, made a few notes, then deleted the decrypted version of the file. It was corporate policy that sensitive material could be left
on
the system disk in encrypted form only, never as clear text. He was pleased that his plan was proceeding well. His instincts had been correct: some important discovery had recently been made in Saxon's University of Washington laboratory. That much, at least, was clear. And Saxon's little speech to the others about the importance of secrecy was particularly interesting. Secrecy from whom?

He reached for the telephone. He would call Saxon in Seattle to make a friendly inquiry as to how things were working out with the laboratory 'setbacks' Saxon had mentioned on Thursday. Saxon's reply would be very telling. Pierce smiled.

10

Saturday Afternoon, October 9

Allan Saxon cursed fluently as he threaded his BMW through the football traffic on Montlake Boulevard. When he had suggested that they meet at the lab at twelve-thirty, he'd forgotten that the Huskies would be meeting their latest victim at the stadium at the same time. He was already running late, even without this traffic crush.

He'd been delayed by a curious telephone call from Martin Pierce, who had called from San Francisco to ask about the 'reverses' he'd mentioned on Thursday in connection with the new experimental equipment. The nosy bastard. Saxon smiled as he thought how he had deceived Pierce by describing a mysterious implosion that had destroyed some of the equipment. He had given not even a hint of the twistor effect. If this hand is played right, he thought, I can cut all ties with Pierce and his sleazy crowd, secure all the application patent rights for the effect, and perhaps collect a Nobel prize as a bonus.

Finally Saxon reached the east gatehouse of the campus. He drove around the paying customers, pointing to the annual permit sticker on his windshield when the guard looked up. He followed the curving road around the campus past the Faculty Center and the Engineering Library to the turnoff for the rear of Physics Hall. When he reached the small parking area behind the building he was relieved to see that one lone spot had not yet been expropriated by the football crowd. It was marked with a wheelchair symbol and a DISABILITY PERMIT ONLY sign.
But
it wouldn't be checked on Saturday, he decided. He pulled in.

Entering the laboratory, he found David Harrison and Victoria Gordon already there. Harrison was sitting at the computer console, and Victoria was energetically cranking the antique Wimshurst machine that Allan recognized from twenty years of E&M lecture demonstrations. A round brass doorknob was suspended from a transparent cord, perhaps monofilament fishing line, at the center of the apparatus, and a fine wire connected it to the whirling glass and metal contraption. A curved piece of aluminum sheet was clamped in position near the doorknob, and a piece of coaxial cable led from the aluminum and its stand to an oscilloscope nearby, which in turn was connected to the control console by a flat gray ribbon lead.

'Now!' said Harrison, and Victoria touched a C-shaped conductor across the electrodes of the machine, producing a fat blue spark and a loud
crack,
'OK,' said Harrison, 'I've got the calibration. Let's do the real thing.' Already at it, thought Saxon, seating himself in the wooden chair as he tried to understand what they were doing.

Victoria cranked again, and the glass disks spun. Finally she said, That ought to do it, David.' He nodded and did something behind the console. The characteristic
pop
of the twistor transition echoed through the room and the doorknob disappeared. Victoria rose and ran to the console. Saxon followed her.

'Wow! It's true!' said Harrison, pointing to a pair of jagged curves on the monitor screen.

'What's true?' said Saxon. 'What are you people up to?'

'We're investigating electric field effects,' said Victoria enthusiastically. 'The question is, if we put an electrically charged object through the twistor transition, what happens to the electric field outside the transition region?
If
the E-field just stopped at the boundary, that would violate Gauss's law, wouldn't it?'

Saxon nodded uncertainly, grappling to visualize the problem. 'Sure,' he said finally, 'electric field lines have to stop and start on charges, so you can't simply chop them off.'

'Right!' said Harrison. 'So the question is, what does happen? I bought a doorknob and some fishing line on my way in and snarfed the Wimshurst machine from the lecture demonstration setup room. We charged the doorknob negative, and then twisted it. We compare that with discharging the doorknob with a spark.'

He gestured at the screen. 'Our nifty new sub-nanosecond digital oscilloscope saved both traces and then dumped them to the computer, and here they are. The spark kills the field fast, on the lower curve. But when the doorknob disappears, the trace falls much more slowly. That's just what you'd expect if all the extra electrons were left behind, probably attached to air molecules on the surface of the field boundary. They'd have to travel through air at a slow diffusion rate to get to grounded conductors and kill the field. So the electric field stays around much longer. Only electrically neutral objects can make the transition. With a charged object, you leave the charges behind.'

'That's a very nice result, Harrison,' said Saxon. 'You two are doing very well. How can I help? I came in to provide some ideas, but you don't have any shortage of them at the moment.' Saxon was feeling a bit unnecessary. He didn't know what to suggest next. Then, too, there was the stack of papers and proposals on his desk awaiting review. 'Maybe I should leave you to finish what you're doing and check back later.'

'Sure, Allan,' said Harrison, taking the hint, 'if you have other things you need to do . . . '

'Well, as a matter of fact, I have some reviewing to do, if you're sure you can spare me,' said Saxon. He
noticed
Victoria frowning slightly. She walked over to the oscilloscope cart and watched the screen closely, then twisted a knob.

'No problem,' said Harrison. 'But Allan, if you've got a minute, there is something else we need to talk about. I've been thinking over our discussion last night about secrecy. I just can't do it that way. We need help in understanding what's going on here. This is too important to keep sitting on it. We've got to go public, and we must do it very soon. If we don't, we're cutting ourselves off from the ideas and stimulation of the department and the whole physics community.'

Saxon frowned, dismayed at the direction of the conversation. To his left Victoria was still peering at the oscilloscope.

'Science can't progress that way,' Harrison continued. Tor your one example of a guy who was done out of his recognition there are lots of examples of people who published quickly with no bad consequences. And there are examples of people who sat on a discovery until someone else discovered it and walked away with the credit. I left Los Alamos to come here because I don't like secrecy in physics research. I don't tolerate it any better here than there.'