October 30, 2002
A CASE IN POINT:A New View of Our Universe: Only One of Many (DENNIS OVERBYE, October 29, 2002, NY Times)
The prospect of this plethora of universes has brought new attention to a philosophical debate that has lurked on the edges of science for the last few decades, a debate over the role of life in the universe and whether its physical laws are unique--or, as Einstein once put it, "whether God had any choice."
Sprinkled through the Standard Model, the suite of equations that describe all natural phenomena, are various mysterious constants, like the speed of light or the masses of the elementary particles, whose value is not specified by any theory now known.
In effect, the knobs on nature's console have been set to these numbers. Scientists can imagine twiddling them, but it turns out that nature is surprisingly finicky, they say, and only a narrow range of settings is suitable for the evolution of complexity or Life as We Know It.
For example, much of the carbon and oxygen needed for life is produced by the fusion of helium atoms in stars called red giants.
But a change of only half a percent in the strength of the so-called strong force that governs nuclear structure would be enough to prevent those reactions from occurring, according to recent work by Dr. Heinz Oberhummer of Vienna University of Technology. The result would be a dearth of the raw materials of biology, he said.
Similarly, a number known as the fine structure constant characterizes the strength of electromagnetic forces. If it were a little larger, astronomers say, stars could not burn, and if it were only a little smaller, molecules would never form.
In 1974, Dr. Brandon Carter, a theoretical physicist then at Cambridge, now at the Paris Observatory in Meudon, pointed out that these coincidences were not just luck, but were rather necessary preconditions for us to be looking at the universe.
After all, we are hardly likely to discover laws that are incompatible with our own existence.
That insight is the basis of what Dr. Carter called the anthropic principle, an idea that means many things to many scientists. Expressed most emphatically, it declares that the universe is somehow designed for life. Or as the physicist Freeman Dyson once put it, "The universe in some sense must have known that we were coming."
This notion horrifies some physicists, who feel it is their mission to find a mathematical explanation of nature that leaves nothing to chance or "the whim of the Creator," in Einstein's phrase.
Here's an example that nicely illustrates yesterday's quote of the day, with scientists driven less by a dispassionate and objective search for "truth" than by personal distaste for religion. At some point, their ideological mission has to warp their theories and lead others to accept them no matter how dubious. Posted by Orrin Judd at October 30, 2002 1:46 PM