Wan-To was not at all color-blind—not even as much so as all human beings are, by the physical limitations of their cells as well as by their habit of living at the bottom of a well of murky air. That is to say, he wasn't limited to the optical frequencies. His eyes saw all the electromagnetic radiation there was. The difference between X rays and heat was less to him than the difference humans perceive between orange and blue. As long as energy came in photons of any kind, Wan-To saw it.
That was particularly useful to his inquiring mind because of the phenomenon of the redshift; because in the long run it was only the redshift that told him how far away, and how long ago, what he was seeing was.
Wan-To had realized that the universe was expanding long before Henrietta Leavitt and Arthur Eddington figured it out. He did it in the same way. He observed that the bright and dark lines in the light produced by ionizing elements in distant galaxies did not quite match the lines in the light from those nearer by.
Humans called those "Fraunhofer lines," and they moved downward with distance. Wan-To didn't call them that, of course, but he knew what they were. They were the light that a given element always produced at a given frequency when one of its electrons leaped to another orbit around the atomic nucleus. And he knew what the redshift meant. It was the Doppler effect (though he did not give it that name), caused by the fact that that particular object was moving away from him. The more it shifted, the faster the object was running away.
It had taken Wan-To very little time (oh, maybe a couple of million years—just the wink of an eye, really) to fill in all the gaps in his understanding and realize that the faster the objects moved the farther away they were; and thus that the universe was expanding! Everything was running away from everything else—everywhere!
And, as Wan-To also was aware that every time he looked at an object a billion light-years away he was also looking a billion years into the past, he understood that he was looking at a history of the universe.
The whole thing was arranged in shells layered around him, separated by time as well as space. What Wan-To saw nearby was galaxies more or less like his own. They contained billions of stars, and they had recognizable structures. Mostly they whirled slowly around their centers of gravity, like the spirals of M-31 in Andromeda. Some of them had fierce radiation sources at their cores, no doubt immense black holes. Some were relatively placid. But they were all, basically, pretty much alike.
But that was only true of the "recent" shell. Farther out it got different.
Around a redshift of 1 (say, at a time perhaps six billion years after the Big Bang, when the universe was only half its present size—about when Wan-To himself had been born, in fact) most galaxies seemed to have pretty well finished their burst of star formation. Farther and earlier, their gas clouds were still collapsing into the clumps that squeezed themselves into nuclear fusion and became stars.
At redshifts up to 3 lay quasars. That was where the galaxies themselves were being born. By redshift 3 all the objects were running away from him at nearly nine-tenths the speed of light, and it was getting to the point where nothing further was ever going to be seen because they were nearing the "optical limit"—the limit of distance and velocity at which the object was receding so fast that its light could never reach Wan-To at all. And the time he was seeing was getting close to the era of the Big Bang itself.
That was a very interesting region to Wan-To. It was there, in that farthest of the concentric shells of the universe, that he found the domain of the blue fuzzies—the tiny, faint, blue objects that must be newborn galaxies, tens of billions of them, so far away that even Wan-To's patient eyes could not resolve them into distinct shapes.
The blue fuzzies propounded any number of riddles to Wan-To's curious mind. The first, and the easiest to solve, was why the blue fuzzies were blue. Wan-To came up with the answer. The blue light he was seeing came from the brightest line produced by the hydrogen atom when it gets excited. (Sometimes this line was called the Lyman-alpha line, in honor of the human scientist who first studied it in detail—but not by Wan-To.) At its source, that line wasn't visible to human eyes at all; it was in the far ultraviolet. But at a redshift of 3 or 4 it wound up looking blue.
The biggest question was what lay beyond the blue fuzzies. And that, Wan-To recognized with annoyance, was something he could never discover by seeing it. Not just because of their distance, pushing right up against the optical limit. Most of all because there wouldn't be anything to see. Until the gas clouds that formed galaxies began to collapse they simply didn't radiate at all.
Wan-To writhed about in his warm, cozy core, very dissatisfied with the fact that natural law kept him from knowing everything. There should be some way! If not to see, then at least to deduce. There were all sorts of clues, he told himself, if only he had the wit to understand them—
The call that came in then broke his concentration.
What an annoyance! Especially as he certainly didn't want to talk to any of his siblings just then.
But then he realized, astonished, that the call wasn't from a sibling at all. It was from that contemptible, low-level intelligence, his Matter-Copy Number Five, which had had the incredible presumption to dare to call him.
It took even Wan-To's vast intellect a while to understand what Five was trying to tell him. No, Five insisted, the object it had destroyed was not one of those quaint, inanimate matter things like comets or asteroids. It was an artifact. It was propelled. It had its own energy source—which, Five had determined, came from something that was very rare indeed in the inanimate universe.
The artifact's energies were definitely derived from antimatter.
Antimatter! Wan-To was astonished. Even Wan-To had never personally experienced the presence of antimatter, though of course he had long since understood that it might exist and sometimes, rarely, did exist in small, very temporary quantities. But even that wasn't quite the most astonishing thing. Stranger still was Five's report that small, independent entities—made of matter—had come floating down to the surface of its planet in a container that the large artifact had launched. And they were still there.
Wan-To had long since forgotten any resentment he had had at Five's impudence in disturbing him. This new development was too interesting.
Of course, it wasn't important. There was no way such tiny, limited creatures could affect anything Wan-To was interested in. Not to mention that there was something about them that Wan-To found repellent, queer, repulsive. It was not easy for him to understand how they could be alive at all.
To be sure, humans would have had just as much trouble understanding Wan-To. The reasons would have been much the same, but reversed in sign. The perceptual universe of matter creatures like human beings was Newtonian; Wan-To's was relativistic and quantum-mechanical. The Newtonian world view was as instinctively alien to Wan-To as quantum mechanics was to a human, because he himself was a quantum-mechanical phenomenon. Not even the spookiest particles were strange to him, because they were what he was made up of and lived among. He could examine them all as easily as a human baby examines its fingers and toes—and in much the same way, with all of his senses, as an infant peers at them, and touches them, and flexes them, and does its best to put them into its mouth.
But when those same particles slowed down and bound their energies into quiescence—when they congealed into solid "matter"—he found them very distasteful indeed.
It struck him as quite odd that his matter-copy on Nebo didn't seem to share his distaste for those repellently solid things it had discovered there. Worse than that. There were the small, active ones that had presented themselves without warning on the surface of the planet, and the doppel admitted humbly that it was not actually destroying them, but was indeed apparently helping them survive.