On the Second Day, Part 1: Feeling Gravity's Pull

Then God said, “Let there be a firmament in the midst of the waters / and let it divide the waters from the waters” / Thus God made the firmament / and divided the waters which were under the firmament / from the waters which were above the firmament/ and it was so / And God called the firmament Heaven / So the evening and the morning were the second day.
The key word for the second day is “firmament,” an old word you don’t encounter much outside of English class. To explain firmament I think of Perry Como and Bobby Sherman: There’s an old song that starts “The bluest skies you’ve ever seen are in Seattle,” and if you imagine just how solid the blue above you looks on one of those August Seattle days, you can understand the ancient notion that the sky is a big, strong dome above us. (Maybe “dome” for most people and “shell” for the ancients who thought of the world as a sphere – some did, you know.) The firmament was obviously strong, and the ancients supposed it to be made of the strongest thing they knew of, which would be metal. It was also supposed to be the barrier between this world and the next. I can’t report that this ancient conception was scientifically right; but I can tell you is that there are strong things that separate us from everything else (this world from the next one over), and they came about on the second day. It’s not a shell of metal, it’s a shell of blue light, but it’s held together by something that is just as powerful as metal in the long run. When I think of what holds up the heavens, I think of the force that holds the earth together and holds the earth to the sun to keep it from spinning into space. So, on the second day, I’d say God created gravity – and gravity, in turn, created metal in the heavens, rather than a heavens made of metal.


Physicists looking at matter today can see four different kinds of forces, each with different “shapes,” strengths, locations, and other properties. Two of the four are what hold the centers of atoms together, one is the electromagnetism that causes magnets and charged particles to stick together, and the last one is gravity, which it’s not too far wrong to say holds everyTHING together. Gravity is always the odd man out when you talk to a physicist: the two atomic forces and electromagnetism are similar enough that you can see how they go together, mathematically speaking. You can use the same kinds of equations to talk about them (called the Standard Model). Gravity, on the other hand, is so weak that we can’t see it (yet) and can’t fit it together with the other three forces (yet). Mathematically, it’s the problem child. But gravity is special because it’s inclusive: everything that is made of matter can both give and take tugs of gravity on everything else made of matter, and this can be from a significant distance.


Because gravity is so different, it makes sense that it’s the one force that separated from the others first, after the Big Bang. All that expanding matter started to clump up into clouds of dust, and some of the dust started to clump up into bigger clumps. The bigger the clump, the more its gravitational pull and the bigger it became. From this clumping we got stars and galaxies of stars and clusters of galaxies. The dust was very gaseous and nebulous and poorly formed, but gravity pulled it together into spherical stars with the same kind of crisp shape you see in our sun. God set up gravity, at the moment of creation, to shape the stars out of the matter that spilled out of the Big Bang. It’s as effective as if he had rolled the stars out of interstellar Play-Dough, or folded them up like so many boxes, although a little more elegant. When I look at the universe I see that God likes elegance, especially when it comes to the fundamental forces that mold space and time.



Gravity is weak enough that you can defeat it (temporarily) by jumping into the air, even at the young age of three years old. But it is strong, too. Not only did it form the stars, but some stars got so big that deep inside the pressure of all that stuff squeezing down made a furnace where those strong atomic forces themselves start to melt down. Atoms got mashed together so tightly they started to fuse together, making new atoms and a little extra energy to burn (therefore, stars are both hot and bright). The new atoms are more complex, mashed-together versions of the old ones. For example, one atom of hydrogen is made up of two small parts: one proton and one electron. In the center of a star, a bunch of hydrogen gets compressed so tight that the protons start sticking togther, and when two protons stick together, that’s the core of a helium atom. Three protons = a lithium core, and that’s a metal already! In fact, sometimes the stars themselves break down with a huge supernova bang, and the forces from this are so intense that there’s a little mini-creation of very complex atoms bursting out from the site. Metals are complex atoms that may have been formed this way – from weak but persistent gravity overcoming the stronger forces.


The concept of all these stars forming from the amorphous clouds of matter, knit together by gravity, is similar in my mind to God’s word separating waters from waters on the second day. This weakest but most common and least understandable of all forces started to differentiate the fluid universe, creating spiral-armed galaxies, red giants, supernovas, and from these factories we got lithium and carbon and more and more complex atoms. Gravity is still at work today. Here’s a picture of an infant galaxy forming nearby, relatively recently, and you can sort of see gravity pulling it together:




[Image from the Hubble Space Telescope, http://en.wikipedia.org/wiki/Image:Hubble_-_infant_galaxy.jpg]

I want to give you a paradox here: God is wholly other and different from his creation, but he is also everywhere, and if he’s everywhere, he is very, very near. If he’s omnipresent, he knows when the sparrow falls, when the hairs fall, and he knows every time gravity knits part of his creation together. Don’t make the mistake of thinking because gravity is consistent and understandable that he must be very far away somewhere, watching us from a distance. On the other hand, don't make the opposite mistake of putting the two things together and thinking he is the gravity, he is not, he is its master. Rather, think of gravity as his tool, his servant that does his bidding and does it very well. Gravity does its job so well, and so consistently, that He lets us use it: we can figure out how it works, give it an equation, and predict where the earth was long ago, and where it will be in the future, assuming its “mission” doesn’t change. These physical forces are messengers of grace for all, like the rain falling on everyone.

This consistency means that I can do an experiment today, and tomorrow I can do the same experiment and get the same result. If something is different, I can’t blame gravity or electromagnetism changing on me (at least as a biochemist I can’t – most biochemical forces boil down to force #3, electromagnetism). Also, if I see light coming to me from across the universe, I can assume it came to me straight, according to the rules set down at creation. I don’t have to worry about it hitting any “pockets of irrationality” that alter it on its way to earth. I can assume that the universe is wholly rational and obeys the same laws everywhere, and everything we see sure reinforces that idea. When scientists look at the universe and can see things billions of light-years away, we see that everything is consistent with this underlying rationality. If God didn’t make the universe, there’s no reason it should be rational, or understandable at all (side note: I’m going to apply Ockham’s Razor to shred the multiple-universe counterargument). Yet everywhere we see, if not order, then the underlying order of rationality. This is a subtle argument, to be sure, but I think it’s a strong one that we live in a rational universe, the consistency of which is a pointer to God. The very rationality atheists spend so much time defending, in their minds against the evils of religion, is really a gift of grace. In a sense there’s a distorted witness to the truth in their strident arguments about justice and rationality.
I think God's nearness in the universe comes out most clearly in times of solitude. This may be a result of my introverted nature, or it may be more common than that -- I just hope you can find your way to see God all around. For me, in college, I lived next to a large athletic field that was dark and empty at night. I would walk back and forth across that field, sometimes thinking, sometimes praying, sometimes neither, and somehow no one ever called security on me. I could see the stars bright and the rest of the earth in shadows, no one else around, and I would get a sense that God was near. The flat field of grass seemed holy, burning but not consumed, "charged with the grandeur of God," to quote Gerard Manley Hopkins. In that boring, open, clear field, I saw God's hand. I also knew that the grass was made of carbon atoms and water molecules, and that all those stars were very, very far away, and if I tripped in a hole that I would fall in the dark, because gravity was still doing its job. God's nearness negated none of those facts. The God that was faithful to carve out all this, and to give us a universe where we could reliably repeat events, as much as we wanted, that God was closer to me than anything else, and yet different, An Other, at the same time. From these observations of a regular, repeatable world, you can conclude one of two things that are ultimately opposite to each other: (1) God is either distant "upstairs" somewhere, dead or close to it; or (2) he is close, faithful and consistent in the midst of these elements, upholding all these forces by his word. I choose to conclude the latter. Much of the Bible is the story of working out what God's faithfulness actually means.
So time passed after the Big Bang. Waters continued to separate from waters. In the spiral-arm corner of one nondescript galaxy, a spinning disc of dust started to collect around a massive collection of matter. The center of this became a yellow star, and eight smaller spheres started to form from the disc, all more or less in the same plane, moving in the same direction. The third of the eight spheres developed a relatively large, single moon (possibly from something else coming along and whacking into it early on), and became our planet Earth. The sun’s gravity keeps it in place, the sun’s light keeps it warm, the moon’s gravity keeps it from wobbling too much, and somehow it had liquid water and a richness of the chemicals needed for life.

This is what happened. The question is, when did it happen? How long did it take after the big bang for these events to take place? How old is this dirt we’re standing on? That’s something I want to give you some data for, and data takes time (surprise), so I’ll continue with the question of time in part 2.