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NOTE: The following talk was delivered to the Unitarian-Universalist Fellowship in Charleston and Huntington, W.Va., in Summer 2000. It is reprinted here with permission. By JAMES A. HAUGHT FALL 2000 | PHYSICS HAS profound philosophical implications. We all know what reality is. We're born into it. We live in it. We die in it. We have physical bodies. We eat physical food. We drink physical water. We breathe physical air. We wear physical clothes. Reality is so all-encompassing that we rarely think about it. However, if you study physics, you begin to see that reality isn't quite real, after all. It's a mirage -- a fiction -- a fantasy. Take matter, for instance. Say you knock on a door. That's solid, isn't it? Hard knuckles on hard wood. But wait -- it isn't solid at all. It's an illusion of electrical charges. The negative electron clouds in the atoms of knuckles repel the negative electron clouds of the wood atoms, creating a false impression of hard contact. The same rule applies to virtually all matter. When you step on the floor or sidewalk, or sit in a chair or lie in a bed, you feel tangible firmness only because of negative electron repulsion. If you could shrink to the size of an atom to examine any of these "solid" things, you couldn't really find them. Approaching an atom, you'd come to a blur of electrons. (Of course, you couldn't see them in the usual sense, because they're smaller than the light waves that register on our retinas.) Science books used to say that electrons "whirl" around the atom, rather like the whirl of an airplane propellor. Now they're considered a "standing wave" around the nucleus, somewhat like a balloon. In reality, nobody knows exactly what an electron is -- or a quark, or any other subatomic thing. Sometimes they're particles; sometimes waves. One wag called them "wavicles." Some have electrical charge and some don't. Superstring theory says they're all the same thing -- vibrating loops -- and the direction they vibrate dictates what they are. They're an ultimate mystery. One physicist called them "the dreams of which stuff is made." IF YOU COULD SOMEHOW detect the electron haze, the nucleus at the heart of the atom would be too small to see. It boggles the mind to realize how empty an atom it is. If an atom were the size of a house, the nucleus would be the size of a grain of salt. It's like the far-flung solar system, with the sun a speck at the center. Looking inside an atom would be like looking into the night sky, with its remote planets. That's how far apart the subatomic particles are, relative to each other. (Many years ago, I heard a bizarre theory that our atoms might be solar systems of an unthinkably smaller universe -- and that our solar system might be an atom of an unthinkably bigger universe. Once, the great astronomer Harlow Shapley gave a talk at West Virginia State College. As a gawky young student, I hung around afterward and asked him: "What's the name of the theory that atoms might be solar systems?" He stared at me and said: "The name of it is damn nonsense." Well, I later learned that it's called the Subatomic Universe Theory -- but I think Shapley was correct.) Getting back to the emptiness inside atoms: It's so awesome that you can't comprehend it. The only way to grasp it is to observe what happens when the emptiness is "squeezed out" by gravity, and the particles are compressed down close to each other. This happens in several steps under immense gravity in a collapsing star. First, you must realize that the matter in a star isn't like matter on earth. Here, we have three states: solid, liquid and gas. Solids occur when atoms lock onto each other in what is called a crystal lattice. Liquids occur when heat makes the atoms so agitated they break out of the lattice and slide around each other. Gas occurs when more heat makes them so jumpy they break loose and ricochet in open space. But stars have a fourth state of matter: plasma. Intense gravity and heat destroy the orbit patterns of atoms, creating a "soup" dotted with roaming nuclei. Without orbits to shield them, the nuclei collide with each other and fuse. This nuclear fusion is what makes stars burn (and makes hydrogen bombs). Its incredible power derives from a tiny amount of matter converted into pure energy under Einstein's famous formula: E=MC2. Any mass of material, if it's big enough for its own gravity to squeeze it into plasma, becomes a star. The planet Jupiter is almost large enough. In fact, astrophysicists think a tiny amount of fusion is occurring in Jupiter's heart. Actually, every atom in our bodies, and virtually every atom on this planet, was forged by fusion inside some star. "We are made of star stuff," Carl Sagan used to say. Star fusion can form nuclei only as heavy as iron. All heavier elements were created in nova and supenova explosions. Therefore, any gold or silver or lead you possess was made in a space explosion billions of years ago, and the scattered dust coagulated into our solar system, and the heavy atoms coagulated into veins in Planet Earth. PAGE 2: Some really heavy stuff...
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