February 25, 2007
The litany of errors on the Creation, Evolution, and Science Ministries FAQ page contains this little gem:
“The sun is shrinking. This causes a host of problems for old age believers. One is that as the sun shrinks, its gravity weakens. Earth’s orbit around the sun is held in place by the sun’s gravitational pull. If we were a fraction closer to, or further from, the sun, life could not exist on earth. The solar system can’t be old.”
Where to begin? Even if the Sun was shrinking, its gravitational pull on Earth would not “weaken.” This reminds me of Star Trek Season-one, Episode 7 where the ancient planet “Psi 2000″ contracts and “grabs” the Enterprise out of its orbit - quite a howler to anyone who passed high-school physics! The gravitational pull of a spherically symmetric body is equivalent to that of a point mass located at its center - its radius is irrelevant, shrunk or otherwise. But it seems this is Russ Miller’s own idiosyncratic gaff. Other creationist versions like that of ICR, make no mention of weakened gravity.
The ICR tale of the “Shrinking Sun” is more in tune with other YE arguments that use a reported measurement (often wrong), assume it’s constant, and extrapolate back in time with contradictory conclusions for an old earth. Other examples include changes in earth’s magnetic field, sea floor sediment accumulation (without plate tectonics!), and the amount of helium in the atmosphere. Not surprisingly, Russ Miller cites all of these embarassingly wrong claims in his FAQ page.
The “Shrinking Sun” was born in 1979, when astronomers John Eddy and Aram Boornazian presented an abstract at an AAS meeting called, “Secular Decrease in the Solar Diameter, 1836-1953.” This over-interpretation of historical data was subsequently withdrawn by the authors (who never imagined extrapolating their result far back in time) and never submitted to a professional journal for publication. Nevertheless, ICR picked it up immediately and naively extended the shrinkage rate into the indefinite past. This led to a Sun too bright for life sometime within the last million years. The “Shrinking Sun” thus quickly became a part of YE creationist legend under the dubious assumption that it had always been shrinking at the claimed rate. I would address the obvious flaw in this reasoning, but it’s not necessary, because:
The Sun is not shrinking. YE creationist Andrew Snelling chronicles some of the ensuing “debate” on the topic here, as does Old Earth creationist Howard J. Van Till. More important, high-precision studies of helio-seismology have weighed in on the “shrinkage” question. Sverker Johannsson looked at the Shrinking Sun in the light of these observations here. It appears that the Sun has stopped shrinking! But don’t expect YE creationists to stop preaching the Gospel of the Shrinking Sun anytime soon.
December 10, 2006
The “Law,” of course, is the second law of thermodynamics, and the faux controversy between it and evolution was cooked up half a century ago by creationists and repeated almost verbatim by Russ Miller in his NAU/Cline lecture. Never mind that, in all that time, virtually no serious physicist thought there was a genuine conflict here! The idea was championed back in the 60’s by hydrologist/creationist Henry Morris, founder of the Institute for Creation Research. I first became acquainted with it in 1963 at about the age of 8 when my father handed me a copy of Morris’s “Twilight of Evolution” to counter my enthusiasm for plastic dinosaurs and children’s books about the history of life. At 8, I couldn’t understand thermodynamics or the flaws in Morris’s inferences from it, but neither can a large fraction of adults in our culture. This is probably what has led creationists to continue using this argument long after it has been soundly refuted. Thermodynamics flourished in the 19th century in support of theoretical efforts to define how to obtain maximum usable energy from heat flow. The second law has been articulated as, “The Entropy Inventory of the World Tends to a Maximum.” But what is entropy? The classic high-school chemistry answer – “disorder” – disguises a philosophically and mathematically sophisticated concept (see the entropy link for more). In a closed system (no exchange of matter or energy with anything outside), entropy either stays the same or increases. Miller repeated the creationist claim that evolution violates this principle, since it implies that entropy decreases. But every physicist knows that this is an incorrect inference. Life is not in a closed system! It is far from chemical equilibrium embedded in a system of heat flow from the Sun. Entropy reductions in evolution take place locally and do not completely compensate for large global increases. Indeed, nobelist Ilya Prigogine showed that all you need to produce spontaneous order in dissipative systems (like life) is an influx of energy. Miller did seem to try and address the fatal flaw in his own argument by claiming that the “raw energy” (as opposed to “cooked” energy?) of the Sun was of a type that could not produce local entropy decreases. In support of this creationist fiction, he gave no theoretical explanation, but provided suggestive and hand-selected examples of the destructive power of solar energy. Of course he left unmentioned any of myriad examples of local entropy decrease under solar energy, such as the spontaneous organization of cyclonic weather patterns. Alas, the Sun’s radiation is no different from any other type of energy flow with regard to its ability to drive local entropy changes. As the zoologist Dawkins wrote in the 70’s, “Morris’s point about the second law of thermodynamics is pathetic. Surely any chemist would accept that there can be local increases in order fed by energy from outside the local system. This is what happens when you synthesize something over a Bunsen burner.” 
Miller’s faulty reasoning prohibits not only evolution but life itself! Living systems routinely make use of the fact that, in an open system, local decreases of entropy take place in energy flow as long as they do not exceed total increases. Complexity increases dramatically in development from embryo to adult mammal. How does life do this without violating the second law? “Living organisms are open systems since they both take in and expel matter; further, they exchange heat with their surroundings…The organism discards matter with a greater entropy content than the matter it takes in, thereby losing entropy to the environment to compensate for the entropy produced in internal irreversible processes.” (Levine, Ira N. 1978; Physical Chemistry, New York: McGraw-Hill). The entropy deficit life gains for itself is clearly available to fuel one of its fundamental properties: evolution!
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