Greg Benford's resume, outside of writing, is impressive enough for two physics professors (he teaches at UC Irvine and is a fellow at Cambridge University, and an adviser to the White House Council on Space Policy and NASA, to give a partial list) but if you add in his prodigious writing achievements, such as two Nebulas, the John W. Campbell Award, among others, his nineteen novels (including the classic TimescapeJ, numerous short stories as well as various nonfiction work—well, the way I add it up, there must be at least three of him.
Thank heaven one of him was around when I asked for a story for Redshift; you'll note how it slyly incorporates his Cambridge University experience.

Anomalies
Gregory Benford

It was not lost upon the Astronomer Royal that the greatest scientific discovery of all time was made by a carpenter and amateur astronomer from the neighboring cathedral town of Ely. Not by a Cambridge man.
Geoffrey Carlisle had a plain directness that apparently came from his profession, a custom cabinet maker. It had enabled him to get past the practiced deflection skills of the receptionist at the Institute for Astronomy, through the assistant director's patented brush-off, and into the Astronomer Royal's corner office.
Running this gauntlet took until early afternoon, as the sun broke through a shroud of soft rain. Geoffrey wasted no time. He dropped a celestial coordinate map on the Astronomer Royal's mahogany desk, hand amended, and said, "The moon's off by better'n a degree."
"You measured carefully, I am sure."
The Astronomer Royal had found that the occasional crank did make it through the institute's screen, and in confronting them it was best to go straight to the data. Treat them like fellow members of the profession and they softened. Indeed, astronomy was the only remaining science that profited from the work of amateurs. They discovered the new comets, found wandering asteroids, noticed new novae, and generally patrolled what the professionals referred to as local astronomy—anything that could be seen in the night sky with a telescope smaller than a building.
That Geoffrey had gotten past the scrutiny of the others meant this might conceivably be real. "Very well, let us have a look." The Astronomer Royal had lunched at his desk and so could not use a date in his college as a dodge. Besides, this was crazy enough to perhaps generate an amusing story.
An hour later he had abandoned the story-generating idea. A conference with the librarian, who knew the heavens like his own palm, made it clear that Geoffrey had done all the basic work correctly. He had photos and careful, carpenter-sure data, all showing that, indeed, last night after around eleven o'clock the moon was well ahead of its orbital position.
"No possibility of systematic error here?" the librarian politely asked the tall, sinewy Geoffrey.
"Check 'em yerself. I was kinda hopin' you fellows would have an explanation, is all."
The moon was not up, so the Astronomer Royal sent a quick e-mail to Hawaii. They thought he was joking, but then took a quick look and came back, rattled. A team there got right on it and confirmed. Once alerted, other observatories in Japan and Australia chimed in.
"It's out of position by several of its own diameters," the Astronomer Royal mused. "Ahead of its orbit, exactly on track."
The librarian commented precisely, "The tides are off prediction as well, exactly as required by this new position. They shifted suddenly, reports say."
"I don't see how this can happen," Geoffrey said quietly.
"Nor I," the Astronomer Royal said. He was known for his understatement, which could masquerade as modesty, but here he could think of no way to underplay such a result.
"Somebody else's bound to notice, I'd say," Geoffrey said, folding his cap in his hands.
"Indeed," the Astronomer Royal suspected some subtlety had slipped by him.
"Point is, sir, I want to be sure I get the credit for the discovery."
"Oh, of course you shall." All amateurs ever got for their labors was their name attached to a comet or asteroid, but this was quite different. "Best we get on to the IAU, ah, the International Astronomical Union," the Astronomer Royal said, his mind whirling. "There's a procedure for alerting all interested observers. Establish credit, as well."
Geoffrey waved this away. "Me, I'm just a five-inch 'scope man. Don't care about much beyond the priority, sir. I mean, it's over to you fellows. What I want to know is, what's it mean?"

Soon enough, as the evening news blared and the moon lifted above the European horizons again, that plaintive question sounded all about. One did not have to be a specialist to see that something major was afoot.
"It all checks," the Astronomer Royal said before a forest of cameras and microphones. "The tides being off true has been noted by the naval authorities round the world, as well. Somehow, in the early hours of last evening, Greenwich time, our moon accelerated in its orbit. Now it is proceeding at its normal speed, however."
"Any danger to us?" one of the incisive, investigative types asked.
"None I can see," the Astronomer Royal deflected this mildly. "No panic headlines needed."
"What caused it?" a woman's voice called from the media thicket.
"We can see no object nearby, no apparent agency," the Astronomer Royal admitted.
"Using what?"
"We are scanning the region on all wavelengths, from radio to gamma rays." An extravagant waste, very probably, but the Astronomer Royal knew the price of not appearing properly concerned. Hand-wringing was called for at all stages.
"Has this happened before?" a voice sharply asked. "Maybe we just weren't told?"
"There are no records of any such event," the Astronomer Royal said. "Of course, a thousand years ago, who would have noticed? The supernova that left us the Crab nebula went unreported in Europe, though not in China, though it was plainly visible here."
"What do you think, Mr. Carlisle?" a reporter probed. "As a non-specialist?"
Geoffrey had hung back at the press conference, which the crowds had forced the Institute to hold on the lush green lawn outside the old Observatory Building. "I was just the first to notice it," he said. "That far off, pretty damned hard not to."
The media mavens liked this and coaxed him further. "Well, I dunno about any new force needed to explain it. Seems to me, might as well say its supernatural, when you don't know anything."
This the crowd loved. super amateur says moon is supernatural soon appeared on a tabloid. They made a hero of Geoffrey. "AS OBVIOUS AS YOUR FACE" SAYS GEOFF. The London Times ran a full-page reproduction of his log book, from which he and the Astronomer Royal had worked out that the acceleration had to have happened in a narrow window around ten P.M., since no observer to the east had noticed any oddity before that.
Most of Europe had been clouded over that night anyway, so Geoffrey was among the first who could have gotten a clear view after what the newspapers promptly termed the "Anomaly," as in ANOMALY MAN STUNS ASTROS.
Of the several thousand working astronomers in the world, few concerned themselves with "local" events, especially not with anything the eye could make out. But now hundreds threw themselves upon the Anomaly and, coordinated out of Cambridge by the Astronomer Royal swiftly outlined its aspects. So came the second discovery.
In a circle around where the moon had been, about two degrees wide, the stars were wrong. Their positions had jiggled randomly, as though irregularly refracted by some vast, unseen lens.

Modern astronomy is a hot competition between the quick and the dead—who soon become the untenured.
Five of the particularly quick discovered this Second Anomaly. They had only to search all ongoing observing campaigns and find any that chanced to be looking at that portion of the sky the night before. The media, now in full bay, headlined their comparison photos. Utterly obscure dots of light became famous when blink-comparisons showed them jumping a finger's width in the night sky, within an hour of the ten P.M. Anomaly Moment.
"Does this check with your observations?" a firm-jawed commentator had demanded of Geoffrey at a hastily called meeting one day later, in the auditorium at the Institute for Astronomy. They called upon him first, always—he served as an anchor amid the swift currents of astronomical detail.
Hooting from the traffic jam on Madingley Road nearby nearly drowned out Geoffrey's plaintive, "I dunno. I'm a planetary man, myself."
By this time even the nightly news broadcasts had caught on to the fact that having a patch of sky behave badly implied something of a wrenching mystery. And no astronomer, however bold, stepped forward with an explanation. An old joke with not a little truth in it—that a theorist could explain the outcome of any experiment, as long as he knew it in advance—rang true, and got repeated. The chattering class ran rife with speculation.
But there was still nothing unusual visible there. Days of intense observation in all frequencies yielded nothing.
Meanwhile the moon glided on in its ethereal ellipse, following precisely the equations first written down by Newton, only a mile from where the Astronomer Royal now sat, vexed, with Geoffey. "A don at Jesus College called, fellow I know," the Astronomer Royal said. "He wants to see us both."
Geoffrey frowned. "Me? I've been out of my depth from the start."
"He seems to have an idea, however. A testable one, he says."
They had to take special measures to escape the media hounds. The institute enjoys broad lawns and ample shrubbery, now being trampled by the crowds. Taking a car would guarantee being followed. The Astronomer Royal had chosen his offices here, rather than in his college, out of a desire to escape the busyness of the central town. Now he found himself trapped. Geoffrey had the solution. The institute kept bicycles for visitors, and upon two of these the men took a narrow, tree-lined path out the back of the institute, toward town. Slipping down the cobbled streets between ancient, elegant college buildings, they went ignored by students and shoppers alike. Jesus College was a famously well-appointed college along the Cam River, approachable across its ample playing fields. The Astronomer Royal felt rather absurd to be pedaling like an undergraduate, but the exercise helped clear his head. When they arrived at the rooms of Professor Wright, holder of the Wittgenstein Chair, he was grateful for tea and small sandwiches with the crusts cut off, one of his favorites.
Wright was a post-postmodern philosopher, reedy and intense. He explained in a compact, energetic way that in some sense, the modern view was that reality could be profitably regarded as a computation.
Geoffrey bridled at this straightaway, scowling with his heavy eyebrows. "It's real, not a bunch of arithmetic."
Wright pointedly ignored him, turning to the Astronomer Royal. "Martin, surely you would agree with the view that when you fellows search for a Theory of Everything, you are pursuing a belief that there is an abbreviated way to express the logic of the universe, one that can be written down by human beings?"
"Of course," the Astronomer Royal admitted uncomfortably, but then said out of loyalty to Geoffrey, "All the same, I do not subscribe to the belief that reality can profitably be seen as some kind of cellular automata, carrying out a program."
Wright smiled without mirth. "One might say you are revolted not by the notion that the universe is a computer, but by the evident fact that someone else is using it."
"You gents have got way beyond me," Geoffrey said.
"The idea is, how do physical laws act themselves out?" Wright asked in his lecturer voice. "Of course, atoms do not know their own differential equations." A polite chuckle. "But to find where the moon should be in the next instant, in some fashion the universe must calculate where it must go. We can do that, thanks to Newton."

The Astronomer Royal saw that Wright was humoring Geoffrey with this simplification, and suspected that it would not go down well. To hurry Wright along he said, "To make it happen, to move the moon—"
"Right, that we do not know. Not a clue. How to breathe fire into the equations, as that Hawking fellow put it—"
"But look, nature doesn't know maths," Geoffrey said adamantly. "No more than I do."
"But something must, you see," Professor Wright said earnestly, offering them another plate of the little cut sandwiches and deftly opening-a bottle of sherry. "Of course, I am using our human way of formulating this, the problem of natural order. The world is usefully described by mathematics, so in our sense the world must have some mathematics embedded in it."
"God's a bloody mathematician?" Geoffrey scowled.
The Astronomer Royal leaned forward over the antique oak table. "Merely an expression."
"Only way the stars could get out of whack," Geoffrey said, glancing back and forth between the experts, "is if whatever caused it came from there, I'd say."
"Quite right." The Astronomer Royal pursed his lips. "Unless the speed of light has gone off, as well, no signal could have rearranged the stars straight after doing the moon."
"So we're at the tail end of something from out there, far away," Geoffrey observed.
"A long, thin disturbance propagating from distant stars. A very tight beam of ... well, error. But from what?" The Astronomer Royal had gotten little sleep since Geoffrey's appearance, and showed it.
"The circle of distorted stars," Professor Wright said slowly, "remains where it was, correct?"
The Astronomer Royal nodded. "We've not announced it, but anyone with a cheap telescope—sorry, Geoffrey, not you, of course—can see the moon's left the disturbance behind, as it follows its orbit."
Wright said, "Confirming Geoffrey's notion that the disturbance is a long, thin line of—well, I should call it an error."
"Is that what you meant by a checkable idea?" the Astronomer Royal asked irritably.
"Not quite. Though that the two regions of error are now separating, as the moon advances, is consistent with a disturbance traveling from the stars to us. That is a first requirement, in my view."
"Your view of what?" Geoffrey finally gave up handling his small sherry glass and set it down with a decisive rattle.
"Let me put my philosophy clearly," Wright said. "If the universe is an ongoing calculation, then computational theory proves that it cannot be perfect. No such system can be free of a bug or two, as the programmers put it."
Into an uncomfortable silence Geoffrey finally inserted, "Then the moon's being ahead, the stars—it's all a mistake?"
Wright smiled tightly. "Precisely. One of immense scale, moving at the speed of light."
Geoffrey's face scrunched into a mask of perplexity. "And it just— jumped?"
"Our moon hopped forward a bit too far in the universal computation, just as a program advances in little leaps." Wright smiled as though this were an entirely natural idea.
Another silence. The Astronomer Royal said sourly, "That's mere philosophy, not physics."
"Ah!" Wright pounced. "But any universe that is a sort of analog computer must, like any decent digital one, have an error-checking program. Makes no sense otherwise."
"Why?" Geoffrey was visibly confused, a craftsman out of his depth.
"Any good program, whether it is doing accounts in a bank, or carrying forward the laws of the universe, must be able to correct itself." Professor Wright sat back triumphantly and swallowed a Jesus College sandwich, smacking his lips.
The Astronomer Royal said, "So you predict—?"
"That both the moon and the stars shall snap back, get themselves right—and at the same time, as the correction arrives here at the speed of light."
"Nonsense," the Astronomer Royal said.
"A prediction," Professor Wright said sternly. "My philosophy stands upon it."
The Astronomer Royal snorted, letting his fatigue get to him. Geoffrey looked puzzled and asked a question that would later haunt them.

Professor Wright did not have long to wait.
To his credit, he did not enter the media fray with his prediction. However, he did unwisely air his views at High Table, after a particularly fine bottle of claret brought forward by the oldest member of the college. Only a generation or two earlier, such a conversation among the Fellows would have been secure. Not so now. A junior Fellow in po-litical studies proved to be on a retainer from the Times, and scarcely a day passed before Wright's conjecture was known in New Delhi and Tokyo.
The furor following from that had barely subsided when the Astronomer Royal received a telephone call from the Max Planck Institute. They excitedly reported that the moon, now under continuous observation, had shifted instantly to the position it should have, had its orbit never been perturbed.
So, too, did the stars in the warped circle return to their rightful places. Once more, all was right with the world. Even so, it was a world that could never again be the same.
Professor Wright was not smug. He received the news from the Astronomer Royal, who had brought along Geoffrey to Jesus College, a refuge now from the institute. "Nothing, really, but common sense." He waved away their congratulations.
Geoffrey sat, visibly uneasily, through some talk about how to handle all this in the voracious media glare. Philosophers are not accustomed to much attention until well after they are dead. But as discussion ebbed Geoffrey repeated his probing question of days before: "What sort of universe has mistakes in it?"
Professor Wright said kindly, "An information-ordered one. Think of everything that happens—including us talking here, I suppose—as a kind of analog program acting out. Discovering itself in its own development. Manifesting."
Geoffrey persisted, "But who's the programmer of this computer?"
"Questions of first cause are really not germane," Wright said, drawing himself up.
"Which means that he cannot say," the Astronomer Royal allowed himself.
Wright stroked his chin at this and eyed the others before venturing, "In light of the name of this college, and you, Geoffrey, being a humble bearer of the message that began all this ..."
"Oh, no," the Astronomer Royal said fiercely, "next you'll point out that Geoffrey's a carpenter."
They all laughed, though uneasily.
But as the Astronomer Royal and Geoffrey left the venerable grounds, Geoffrey said moodily, "Y'know, I'm a cabinet maker."
"Uh, yes?"
"We aren't bloody carpenters at all," Geoffrey said angrily. "We're craftsmen."
The distinction was lost upon the Royal Astronomer, but then, much else was, these days.

The Japanese had very fast images of the moon's return to its proper place, taken from their geosynchronous satellite. The transition did indeed proceed at very nearly the speed of light, taking a slight fraction of a second to jerk back to exactly where it should have been. Not the original place where the disturbance occurred, but to its rightful spot along the smooth ellipse. The immense force needed to do this went unexplained, of course, except by Professor Wright's Computational Principle.
To everyone's surprise, it was not a member of the now quite raucous press who made the first telling gibe at Wright, but Geoffrey. "I can't follow, sir, why we can still remember when the moon was in the wrong place."
"What?" Wright looked startled, almost spilling some of the celebratory tea the three were enjoying. Or rather, that Wright was conspicuously relishing, while the Astronomer Royal gave a convincing impression of a man in a good mood.
"Y'see, if the error's all straightened out, why don't our memories of it get fixed, too?"
The two learned men froze.
"We're part of the physical universe," the Astronomer Royal said wonderingly, "so why not, eh?"
Wright's expression confessed his consternation. "That we haven't been, well, edited ..."
"Kinda means we're not the same as the moon, right?"
Begrudgingly, Wright nodded. "So perhaps the, ah, 'mind' that is carrying out the universe's computation cannot interfere with our— other—minds."
"And why's that?" the Astronomer Royal a little too obviously enjoyed saying.
"I haven't the slightest."

Light does not always travel at the same blistering speed. Only in a vacuum does it have its maximum velocity.
Light emitted at the center of the sun, for example—which is a million times denser than lead—finds itself absorbed by the close-packed ionized atoms there, held for a tiny sliver of a second, and then released. It travels an infinitesimal distance, then is captured by yet another hot ion of the plasma, and the process repeats. The radiation random-walks its way out to the solar surface. In all, the passage from the core takes many thousands of years. Once free, the photon reaches Earth in a few minutes.
Radiation from zones nearer the sun's fiery surface takes less time because the plasma there is far less dense. That was why a full three months elapsed before anyone paid attention to a detail the astronomers had noticed early on and then neglected.
The "cone of chaos" (as it was now commonly called) that had lanced in from the distant stars and deflected the moon had gone on and intersected the sun at a grazing angle. It had luckily missed Earth, but that was the end of the luck.
On an otherwise unremarkable morning, Geoffrey rose to begin work on a new pine cabinet. He was glad to be out of the media glare, though still troubled by the issues raised by his discovery. Professor Wright had made no progress in answering Geoffrey's persistent questions. The Astronomer Royal was busying himself with a Royal commission appointed to investigate the whole affair, though no one expected a commission to actually produce an idea. Geoffrey's hope—that they could "find out more by measuring," seemed to be at a dead end.
On that fateful morning, out his bedroom window, Geoffrey saw a strange sun. Its lumpy shape he quickly studied by viewing it through his telescope with a dark glass clamped in place. He knew of the arches that occasionally rose from the corona, vast galleries of magnetic field lines bound to the plasma like bunches of wire under tension. Sprouting from the sun at a dozen spots stood twisted parodies of this, snaking in immense weaves of incandescence.
He called his wife to see. Already voices in the cobbled street below were murmuring in alarm. Hanging above the open marsh lands around the ancient cathedral city of Ely was a ruby sun, its grand purple arches swelling like blisters from the troubled rim.
His wife's voice trembled. "What's it mean?"
"I'm afraid to ask."
"I thought everything got put back right."
"Must be more complicated, somehow."
"Or a judgment." In his wife's severe frown he saw an eternal human impulse, to read meaning into the physical world—and a moral message as well.
He thought of the swirl of atoms in the sun, all moving along their hammering trajectories, immensely complicated. The spike of error must have moved them all, and the later spike of correction could not, somehow, undo the damage. Erasing such detail must be impossible. So even the mechanism that drove the universal computation had its limits. Whatever you called it, Geoffrey mused, the agency that made order also made error—and could not cover its tracks completely.
"Wonder what it means?" he whispered.
The line of error had done its work. Plumes rose like angry necklaces from the blazing rim of the star whose fate governed all intelligence within the solar system.
Thus began a time marked not only by vast disaster, but by the founding of a wholly new science. Only later, once studies were restored at Cambridge University, and Jesus College was rebuilt in a period of relative calm, did this new science and philosophy—for now the two were always linked—acquire a name: the field of empirical theology.