Cosmology: Truth or Style?
If you follow cosmology, you’re familiar with WMAP, Type-1a supernovae, gravitational lensing, inflation and a host of technical terms. They seem authoritative because they rely on respectable laws like gravity and general relativity. In an article in Nature today, however, Richard Massey pictured the whole enterprise as a matter of fashion, not fact.
In “Dark is the new black,”1 Massey unloaded a philosophical Pandora box in his attempt to explain why gravitational lensing is the hot new thing in cosmology (as opposed to measuring supernovas and acoustic oscillations):
As scientific fashions come and go, the rivalry between the three houses might be more at home on the catwalks of Paris or Milan. The techniques are at different stages of the same product cycle. Initial hype draws a flurry of excitement, but when systematic physical flaws show up, sober reflection brings a sheepish look back at the design. Some methods may be consigned to a dusty drawer. But the stitch or two of alterations by Schmidt and colleagues has ensured that gravitational lensing will still be on the hot list next season.
Most laymen would have thought science is about searching for truth, not fashion. Massey had just poked holes in lensing techniques – thus the need for “alterations.” Prior to that, he poked holes in the fashion of the 1990s – type-1a supernovae. Remember the hype before the Hubble Space Telescope was launched? Reporters were assuring the public that the increased accuracy of supernova measurements was going to tell us the age and size of the universe to unprecedented precision. In hindsight, that was all a fad:
Initial enthusiasm for using supernovae as cosmic distance indicators, and thus as a probe of the Universe’s expansion, garnered vast allocations of time on ground- and space-based telescopes, and triggered the first plans for a dedicated, all-sky successor to the Hubble Space Telescope. Unfortunately, the explosions were later found to depend on the stars' environment and ingredients, which evolve over cosmic time. Such effects can be parameterized only to a certain precision, and the technique is falling out of fashion.
There’s that word fashion again. What confidence can people have that the latest fashion Massey described will not become tomorrow’s joke? – Oh, that’s so 2009.
Nothing in Massey’s article offered confidence that cosmologists are converging on a correct answer. For instance, speaking of acoustic oscillations, he said, “Larger ground-based telescopes are currently setting out to measure this effect, but seeds of doubt are already emerging about how faithfully real galaxies trace the original ripples.” With supernovae out, and ripples in doubt, that left only gravitational lenses in style – provided they get the needed alterations.
In light of the uncertainties that plagued his article, it would seem astonishing he could begin his article on a triumphal tone. The reader can gauge whether he was just being satirical here; otherwise, it is well deserving of Stupid Evolution Quote of the Week:
Since the Big Bang, the Universe’s initial expansion has been gradually slowed by the gravitational pull from the mass it contains. Most of this mass is in the form of invisible and mysterious dark matter. Today, however, the Universe seems to be re-accelerating under the influence of even weirder stuff dubbed dark energy. For astronomy funding purposes, ‘dark’ is the new black. Almost nothing is understood about either dark matter or dark energy – but both are many times more common than visible matter, and their tug of war will shape the fate of the entire cosmos.
If no reliable technique for measuring these parameters has remained “in fashion” for long, a critic might rightly question the factualness of the statements in the first and second sentences. And if observation is the key ingredient of any science, that critic might also wonder why dark, mysterious unknown stuff (02/28/2008), about which almost nothing is understood, could even become fashionable in the first place in a science lab.
1. Richard Massey, “Cosmology: Dark is the new black,” Nature 461, 740-741 (8 October 2009) | doi:10.1038/461740a.
The prophet Berman warned us about these false teachers back in 2004 (10/06/2004) and in 2007 (09/29/2007). What other profession parades its ignorance like this? What you just learned from Massey’s spilling of the beans is that dark is the new fashion “for astronomy funding purposes.” Yes, you guys, you ought to take up truck driving (11/07/2007). Learn the value of real work for honest money, and the need to watch where you’re going.