Mr g by Alan Lightman Read Free Book Online Page A

not a single dollop of space that could be said to be sleeping. Indeed, the “vacuum” of space seethed with the creation and annihilation of new particles. In these early moments of the new universe, every pinprick of mass flew about with nearly the same speed as the photons, the maximum speed allowed by the laws. Space was a buzzing blur of subatomic particles, whizzing about at fantastic speed in crisscrossing patterns, zipping about and deflecting and colliding with one another. Energy fields lay across the cosmos in vast, floppy blankets, slightly shuddering as they created each new particle or absorbed other particles into their folds. And in every volume of existence, quantum physics held sway. Particles acted as waves, waves as particles. Alternate realities shimmered at every position of space. Matter and energy appeared and disappeared, merged into each other, and exchanged identities. And at the tiniest sizes of somethingness, quantum fluctuations and gravity conspired to tessellate the very geometry of existence.
    It was exhilarating. It was glorious. It was more than I had imagined. At the same time, it was all entirely logical. All of it followed inexorably and irrefutably from the few laws I had laid down. I had to do nothing but sit back and watch as the cosmos unfolded in time.

The Quantification of Reality
    Time. As yet, time was unmeasured and unmeasurable. But that was soon to change, with the formation of hydrogen atoms.
    As Aalam-104729 continued to expand and to cool, there came a point at which it was sufficiently tepid that electrons could be captured and held by protons to form atoms of hydrogen, the simplest of atoms. In each hydrogen atom, a single electron orbited a single proton. Hydrogen atoms were my first atoms. They were lovely. Some were spherical, others ovaloid or dipoloid, depending on the quantum state of the orbiting electron. Patterns within patterns within patterns, all perfect as the number π and precisely determined by the few quantum rules I had given. The atoms glowed as their revolving electrons emitted photons. They faintly hummed. And the atoms gave matter a sponginess, a kind of cushiony texture it did not have before.
    Most importantly, hydrogen atoms served as the first clocks. The light emitted by these atoms vibrated with a precise regularity in time, always exactly the same, each vibration being one tick of the clock. Peak and trough and peak and trough and peak and trough—tick, tick, tick, tick, tick, tick. Now any duration of time could be measured by how many ticks of an atom of hydrogen. In these terms, Aalam-104729 was at this instant 4.52948 x 10 29 atomic ticks old. The first neutrons and protons had begun forming at about 2.5 x 10 9 atomic ticks after the birth of the universe, the first atoms at about 3 x 10 28 . I was somewhat surprised to realize that a great deal of time had already elapsed, at least in terms of the beats of the atoms of hydrogen.
    Now we had clocks. Now time not only existed, but it could also be quantified, it could be measured, it could be carved up into pieces equal to the quantum throbbings of atoms. Now we could do far more than say that something happened in the past. We could say precisely how far in the past. And the duration of happenings and events, the time elapsed between A and B, could be assigned a definite number. The concepts of fast or slow, lazy or brisk gained a definite meaning. At last, I could measure the interval between Aunt Penelope’s great heaves and snores as she lay sleeping (typically 10 20 atomic ticks when she retired in a good mood, less when she was disgruntled). One of Aunt P’s interminable speeches, advising me to do this or that, often took 10 21 or 10 22 ticks. And one of Uncle D’s leisurely walks around the Void occupied between 10 25 and 10 26 ticks. (Compared to these events, my thoughts were so rapid as to be almost instantaneous, occupying a mere one-millionth of one-trillionth of