Chapter 4 Causality
Ravan’s work created quite a stir. Not among the public, who would have been as amazed as they were mystified: they certainly would not hear about it until it had been properly vetted. The Protectorate was keen on scientific progress, but even keener on ensuring that no dangerous technologies could be born; and preferably not even become a gleam in someone’s eye.
Professor Theraney asked Ravan to prepare a paper on his findings and this he circulated among those luminaries with the expertise and clearance to see it. So in relatively short order, Ravan found himself standing before those luminaries and interested Protectorate agents, giving an account of his discovery.
This account went much as he had told his professor except with some simplifications and many colored images. These succeeded in conveying the impression to his audience that they understood what he was saying, especially if they did not.
“So,” asked an elderly man with piercingly intelligent eyes but unrecognized face, “You are saying that we can look into the past, spy on it if you will, but not send things there to change it?”
“I am saying that we can look into the past without changing it, yes.”
“That isn’t quite what I asked.”
“Well…” he started, and stopped.
“Well?” asked the man, somewhat more sharply.
“Well, I have not developed the equations that far. I’ve only looked at the small scales. In those, the past is not changed, no.”
“Would you care to speculate about… other possibilities?”
For a student to be put up as the star in front of such an audience was of course thrilling for the student. In such circumstances it is easy to get carried away into imprudence. But Ravan had noted the silent men and women on the margins of the audience, and remembered the archaeology student.
Well, to be honest, sir, I think the wave equations do allow changing the past, through strange loops in causality, just as they allow physical effects to manifest from non-existent virtual particles, he thought.
“Well, I am sure that physics does not allow causality violations,” he said. And so I am. “Just as the ‘elasticity’ of the wave functions allows us to view the past without changing it, I believe that very elasticity would push back against the creation of any wormhole capable of changing the past. Consider a rubber band or a spring: the more you try to stretch it, the more it pushes back against your attempt. Thus we would be back to unstable wormholes, and causality is preserved.” And that may even be true.
“And how sure are you of that?”
Ravan spread his hands. “I am quite sure that causality cannot be violated. As to the exact mechanism whereby it may be preserved under all circumstances… I am afraid that is beyond me at this point. But causality is fundamental to reality, so I don’t have to fully understand my equations in order to be sure of it.”
The man nodded, and the questions turned to other matters. But Ravan noted that the glances of the silent men remained sharp.
Besides that one moment of danger, the seminar was a great success. At the end, Ravan received many congratulations. His doctorate in physics was a foregone conclusion, and so he embarked on his exceptional career.
When he wrote up the papers that formalized his work, he was careful to restate his assertion that using the technology to change time was impossible. He was even more careful to add statements to the effect of ‘and of course, any such attempt would be extraordinarily dangerous, more dangerous even than atomic weapons.’ The last thing I want, he told himself, is for someone too clever for his or her own good to look too closely into that possibility. It’s the last thing the world needs, too.
If sometimes in the years following he thought he saw an occasional silent watcher in the shadows, perhaps he imagined it.