History of the Imagined Universe

kw: book reviews, history, myths

Subject of the times: The history of everything. Now, a history of what people think about the universe: David Park's The Grand Contraption: The World as Myth, Number, and Chance., published by Princeton University Press. The author is Emeritus Professor of Physics at Williams College. I guess it takes a scientist to cover the subject. Stephen Hawking gave us A Short History of Time. This is a short history of cosmology—or at least cosmological speculation for the most part.

Dr. Park has a lot of ground to cover, 4,000 years of speculative and scientific literature, in 300 pages. He has to do a lot of "we need not follow this further"-ing, to avoid producing a 3,000 or 30,000 page tome.

The historical threads begin with the origin of writing, including an illustration of the world according to ancient Babylon, about the time that Gilgamesh was written down.

The greatest impression I received was of the scale of the universe. When Park writes "world," at least in the latter half of the book "universe" is really what is meant...or perhaps "observable universe."

Observable is the key here. Parallax was discovered very early, but the eye is too crude to measure even the Moon's distance with any accuracy. The earliest attempts placed both Moon and Sun within a few times the earth's size, and the "fixed" stars not much farther away. The spherical earth was known to at least some as early as 500 BC, but the initial estimate of its size was quite large: 40,000 miles in circumference. Eratosthenes, a couple centuries later, came as close as anyone prior to the 1800s, with about 23,000 (may be more; we aren't sure how long his stade was) miles.

It took the Copernican Revolution to push the planets farther away than a few tens of thousands of miles. Kepler, using Brahe's data, used oppositions and quadratures of Earth with Mars to determine its distance to be some tens of millions of miles. The invention of the telescope gave observers at least the uneasy feeling that there were distant stars many times farther yet.

Human understanding of the scale of the universe has steadily increased. The "observable universe" is currently thought to have a radius of about 13 billion light-years. However, if you work the math backwards, using current assumptions about the Big Bang and cosmic expansion since, quasars near "the edge", whose 13-billion-year-old light is just reaching us, would today be more like 75 billion light-years away. Park doesn't mention that. He doesn't need to. A discussion of the implications of Alan Guth's "inflation" hypothesis indicate that the size of the inflated bubble was perhaps a billion light-years, at a time when light had only traveled a trillionth of a trillionth of a meter. So we're not seeing much of what's really out there!

In the early part of the book, he necessarily focuses on religious texts. Only they had origin stories. I found it interesting that all of them, with one exception, imagined the world's creation as an act of sexual procreation, usually an act of incest. The exception? The book of Genesis. (someone is asking, "Does that mean you think Genesis is scientifically accurate?" I means that Genesis does not record ridiculous fantasies. As to science, while that isn't the intent of the Hebrew scriptures, another biblical book contains the earliest description of a spherical Earth, with the division between day and night traveling around it as a rotating circle. The terminator, as seen from elsewhere, perhaps... Hang in there, I may get into Bible stuff someday, though that's not the intent of THIS blog).

Resurfacing: the author emphasizes the continuing sense of wonder on the part of discoverer after discoverer. We also see the continuing, negative reaction by insecure traditionalists. Discoveries remain. Tradition loses its power and becomes irrelevant. Real faith needs no tradition. Real science is delighted at each new unveiling of reality.

No matter how big our universe—and remember, for most people, it is no bigger than that of the Babylonians—we all benefit from the chance to look farther, to see more, and to imagine.