‘But Rotor did. Did that bother you? I wonder. After all, someone on Rotor got ahead of you.’
‘Why should it bother me? The theory is interesting, but the application isn't. If you were to read more of my papers than the titles, you would discover that I say, quite flatly, that hyper-assistance isn't worth the effort.’
‘Rotorians were able to get a vessel far into space and studied the stars.’
‘You're talking about the Far Probe. That enabled Rotor to get parallax measurements for a number of comparatively distant stars, but is that worth the expense they went to? How far did the Far Probe go? Just a few light-months. That's not really very far. As far as the Galaxy is concerned, the Far Probe's extreme position and that of Earth and the imaginary line that can be drawn between them all amounts to a point in space.’
‘They did more than send out the Far Probe,’ said Fisher. ‘The entire Settlement left.’
‘They certainly did. That was in '22, so they've been gone six years now. And all we know is that they left.’
‘Isn't that enough?’
‘Of course not. Where did they go? Are they still alive? Can they still be alive? Human beings have never been isolated on a Settlement. They have always had Earth in the vicinity, and other Settlements, too. Can a few tens of thousands of human beings survive, alone in the Universe, on a small Settlement? We have no idea if that is a psychological possibility. My guess is that it isn't.’
‘I imagine their purpose would be to find a world they could live on. They wouldn't remain on a Settlement.’
‘Come, what world will they find? They've been gone six years. There are exactly two stars they could have reached by now since hyper-assistance can only move them at an average speed equal to that of light. That's Alpha Centauri, a three-star system, four-point-three light-years away, one of the three being a red dwarf. Then there's Barnard's star, a single red dwarf, five-point-nine light-years away. Four stars: a Sun-like star, a near-Sun-like star, and two red dwarfs. The two Sun-likes are part of a moderately close binary and therefore unlikely to have an Earth-like planet in stable orbit. Where do they go next? They won't make it, Crile. I'm sorry. I know that your wife and child were on Rotor, but they won't make it.’
Fisher kept calm. He knew something she didn't. He knew about the Neighbor Star - but that was a red dwarf, too.
He said, ‘Then you think that interstellar flight is impossible?’
‘In a practical sense, yes, if hyper-assistance is all there is.’
Fisher said, ‘You make it sound as though hyper-assistance isn't all there is, Tessa.’
‘It may be all there is. It wasn't long ago when we thought that even that much was impossible and to go further yet-Still, we can at least dream of true hyperspatial flight and true superluminal velocities. If we could go as quickly as we wished for as long as we wished, then the Galaxy, perhaps the Universe, would become one large Solar System, so to speak, and we could have it all.’
‘That's a nice dream, but is it possible?’
‘We've had three All-Settlement Conferences on the matter since Rotor's flight.’
‘Just All-Settlement? What about Earth?’
‘There were Earth observers present, but Earth is not a physicists' paradise these days.’
‘What conclusions did the conference reach?’
Wendel smiled. ‘You're not a physicist.’
‘Leave out the hard parts. I'm curious.’
She merely smiled at him.
Fisher clenched his fist on the table before him. ‘Forget this theory of yours that I'm some sort of secret agent after your information. I have a child out there somewhere, Tessa. You say she's probably dead. What if she's alive? Is there a chance-’
Wendel's smile disappeared. ‘I'm sorry. I did not think of that. But be practical. Finding a Settlement somewhere in a volume of space that is represented by a sphere that, at the present time, is six light-years in radius and is growing ever larger with time is an impossible task. It took us over a century to find the tenth planet, and that was enormously larger than Rotor and a much smaller volume of space had to be combed.’
Fisher said, ‘Hope springs eternal. Is true hyperspatial flight possible? You can say yes or no.’
‘Most say no - if you want the truth. There may be a few who say they can't say, but they tend to mumble.’
‘Does anyone say yes right out loud?’
‘One person that I know of does. I do.’
‘You think it's possible?’ said Fisher with an astonishment he did not have to fake. ‘Do you say that openly, or is it something you tell yourself in the dark of the night?’
‘I've published on the subject. One of those articles you only read the title of. No-one dares agree with me, of course, and I've been wrong before, but I think I'm right now.’
‘Why do the others all think you're wrong?’
‘That's the hard part. It's a matter of interpretation. Hyper-assistance on the Rotorian model, the techniques of which are by now understood in the Settlements generally, by the way, depends on the fact that the product of the ratio of ship speed to light speed, multiplied by time, is a constant, where the ratio of ship speed to light speed is greater than one.’
‘What does that mean?’
‘That means that when you go faster than light, the faster you go, the shorter the time you can maintain the speed, and the longer the time you must go more slowly than light before you can get a boost over it again. The result is that, in the end, your average speed over a particular distance is no greater than the speed of light.’
‘Well?’
‘That makes it sound as though the uncertainty principle is involved, and the uncertainty principle, all of us are convinced, can't be fooled with. If the uncertainty principle is involved, then true hyperspatial flight would seem to be theoretically impossible, and most physicists have come down on that side of the argument, while the rest of them waffle. My view, however, is that what's involved merely seems like the uncertainty principle but isn't, and that true hyperspatial flight is, therefore, not eliminated.’
‘Can the matter be settled?’
‘Probably not,’ said Wendel, shaking her head. ‘The Settlements are definitely not interested in wandering off with mere hyper-assistance. No-one is going to repeat the Rotorian experiment and voyage for years to probable death. On the other hand, neither is any Settlement going to invest an incredible amount of money, resources and effort in order to try to work out a technique that the vast majority of experts in the field are convinced is theoretically impossible.’
Fisher leaned forward, ‘Doesn't that bother you?’
‘Of course it bothers me. I'm a physicist and I'd like to prove that my view of the Universe is the correct one. However, I've got to accept the limits of the possible. It will take enormous sums and the Settlements will give me nothing.’
‘But, Tessa, even if the Settlements are not interested, Earth is - and to any amount.’
‘Really?’ Tessa smiled in what seemed mild amusement and she reached out to stroke Fisher's hair, slowly and sensually. ‘I thought we'd get to Earth eventually.’
34Fisher seized Wendel's wrist and gently drew her hand away from his head. He said, ‘You've been telling me the truth about your opinions of hyperspatial flight, haven't you?’
‘Completely.’
He said, ‘Then Earth wants you.’
‘Why?’
‘Because Earth wants hyperspatial flight, and you're the one important physicist who thinks it can be done.’
‘If you knew that, Crile, why the cross-examination?’
‘I didn't know it until you told me so. The only information I had been given was that you were the most brilliant physicist alive today.’
‘Oh, I am, I am,’ said Wendel mockingly. ‘And you were sent to get me?’
‘I was sent to persuade you.’