Sunday, March 28, 2010

Bodies Made of Diamonds

I was reading an essay in an old book of mine. It dates to 1956 and was published by Scientific American. The paper, by William A. Fowler, then working at the W.K. Kellogg Radiation Laboratory at Cal Tech, is titled “The Origin of the Elements.” Attempts to understand how the elements originated, Fowler tells us, began by measuring their abundance in the cosmos. Now people know this, in a sense, but in another they do not: hydrogen is the most abundant element. If you weighed the cosmos, 76 percent of its weight would be the weight of hydrogen. If you counted all of the atoms, 93 percent of all atoms are hydrogen. Helium, in turn, accounts for 23 percent of the weight and 7 percent of the atoms. What is left? Almost nothing. Of the most abundant elements in our body only hydrogen in water is abundant. Others, like oxygen, carbon, nitrogen, calcium, potassium, etc., are in the 1 percent of weight and the less than 1 percent of atoms in the universe. Our bodies belong to the rarest of rare objects in the cosmos. We have bodies made of diamonds. And that view is not commonly held.

Here’s another wonder to ponder. Fowler traces how elements formed from protons and neutrons after the Big Bang. He mentions George Gamow and Fred Hoyle. Gamow offered the broad hypothesis: everything is made of protons and neutrons—but don’t ask how those two got made. Hoyle produced a plausible theory of the process—actually many interlocking processes—by means of which heavier elements like carbon, nitrogen, and oxygen were formed—also how the really heavy characters like radium could have come into being. Hoyle proposed that elements formed, and still form, inside of stars. But the interesting wrinkle is that the first red giant processing “virgin” hydrogen could only make the basic starting blocks: helium, carbon, oxygen, neon, and a little iron. All of the other, heavier elements—and the lighter nitrogen—required the following sequence: this first sun dies; it spews all of its mass into the cosmos; the handful of newly minted elements, not least a lot of helium, mix with great clouds of virgin hydrogen; that cloud in turn collapses by gravitational forces into a second generation star. Finally, that star, now containing some already heavier elements, will manage to create the whole periodic table. But that sun, too, must die and spew out its product into the void. The products must form planets. A third generation star must then appear and shed its light onto this “diamond” of a world in order to produce from its substance the vehicles that carry us.

Science is a process of looking, seeing, measuring, hypothesizing, and then, later, revising. It amused me to read the following sentence in Fowler’s paper: “Gamow starts from the postulate … that the cosmos started from a core which exploded in a primordial ‘big bang’ some five billion years ago.” I found one of my penciled annotations in the margin, a circle around the word “five” and then a comment. The comment says: “13.5 billion in 2004, 48 years later.”

Yes—look, see, think, and revise. Five hundred years from now the theory might be that a great fiery dragon spat out the elements in anger when challenged by an upstart humanity riding the Starship Enterprise.
The book is The Universe, a Scientific American Book, 1956, New York.

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