Mr g by Alan Lightman Read Free Book Online Page B

one-trillionth of a single atomic tick.) I hesitated to calculate exactly how long I’d been doing absolutely nothing, how long all of us had slept in our torporous amnesia.
    As time and space were connected by the speed of light, the quantification of time naturally led to a quantification of space. Now any length could be measured in terms of the distance traveled by a photon of light during one tick of an atomic clock. In these terms, the diameter of a neutron was one-hundredth of one-millionth of a light-atomic-tick. The diameter of an atom was a hundred thousand times larger. The diameter of the entire universe, judging by how long it took a photon to traverse the distance, was 9 x 10 29 light-atomic-ticks, and growing larger each moment.
    Delighted to have a reliable method to quantify reality, I immediately set about measuring everything I could find. I measured the size of certain quark condensations: 10 −7 light-atomic-ticks. The average size of a matter inhomogeneity: 10 27 light-atomic-ticks. The time for a particular basin of antimatter to annihilate with matter: 1,003 atomic ticks. The time for the universe to double its size: 10 30 atomic ticks.
    Uncle Deva was appalled that I might now lay ruler and clock to the Void. He appreciated what I had achieved, he said, but I was going too far. Too far? Tell me, said my uncle, what do you know about a thing when you know precisely its size and its duration? You know precisely nothing, that’s what you know. But how can you compare the thing to other things? I protested. Why should you compare? said Uncle. Each thing possesses its own special essence, which has nothing to do with anything else. Understand the essence of a thing, said Uncle, and you know everything you need to know. And I guarantee that the essence is not how many what-you-may-call-it atom flicks you’ve got. No sir. You’re only fooling yourself.
    Aunt P looked suspiciously at the loose hydrogen atoms I’d brought back to the Void. Don’t you dare measure me with those gadgets, she said. But I was only … No ifs, ands, or buts, said my aunt. I am
unmeasurable
, and I aim to stay that way. Period. I don’t want some half-witted creature in some universe or other quoting my measurements. Just don’t bring those gadgets into the Void. Let them stay where they are. Amen, said Uncle.
    It seemed that I was the only one who took pleasure in the new clocks and rulers.

Galaxies and Stars
    Bound by causal necessities, requiring not a single touchup or tinker from me, events in Aalam-104729 proceeded on their own with an impressive inevitability. As the universe continued to expand, its material contents cooled further and further. The brilliant displays of light slowly dimmed. And the attractive force of gravity began to dominate and reshape the terrain. Whereas before, small condensations of matter would quickly evaporate under the high heat, now they grew larger and denser. Lumps of material, most of it hydrogen gas, began to condense here and there. In the past history of the universe, matter had been rather evenly spread about, but now there were ridges and valleys, arches, amorphous aggregations, all bunching themselves up into ever denser bulges as each particle of mass gravitationally attracted other particles. The smooth, almost fluid topography of matter before had been beautiful, but these architectural constructions were even more beautiful. There were linear filaments. There were sheets. There were hollowed-out spherical cavities. There were ellipsoids and spheroids and topological hyperboloids. Great clouds of hydrogen gas swirled and flattened and spun out spiral wisps and trails. And within these spinning galaxies of matter, smaller knots of gas formed, collapsed on themselves, and grew denser and hotter—in opposite fashion to the rest of the universe, which was thinning and cooling.
    After 10 31 ticks of the atom clocks, a wondrous new phenomenon occurred. Each knot of gas in each